Weaned piglets face multiple stressors including nutritional transition, environmental changes and pathogenic invasion at a stage when the immune system and intestinal barrier are still immature, making them prone to oxidative stress, barrier damage, immune dysregulation and gut microbiota imbalance, which in turn impairs growth performance and feed efficiency. Against the backdrop of policies promoting “reduced use and prohibition of antibiotics” in the animal husbandry industry, replacing drug dependence with nutritional strategies that modulate immunity and intestinal health has become an inevitable trend. This review systematically summarizes the common stressors in weaned piglets and their impacts on the gut and immune system, with a focus on the roles of nutritional factors (such as functional amino acids, vitamins and trace minerals) and functional additives (including probiotics, prebiotics, plant extracts and organic acids) in supporting intestinal epithelial repair, enhancing antioxidant defense, regulating mucosal and systemic immunity, and reshaping the gut microbiota and its metabolism. It also discusses formulation strategies and practical considerations under different stress conditions. Finally, the review proposes that future research should move from mechanistic exploration toward context-specific application, thereby providing a reference for establishing antibiotic-free, environmentally friendly and efficient piglet production systems.

As one of the energy-feed raw materials, the content of crude protein and amino acid of sorghum is slightly higher than that of corn, and the effective energy value is similar to that of corn. When the price of corn is high, using part of sorghum instead of corn can effectively reduce the feed cost and alleviate the shortage of energy-feed raw materials. However, sorghum was not widely used in pigs because of its anti-nutritional factors, especially in the piglet stage. Therefore, this paper mainly reviewed the differences in nutritional components of different types of sorghum, the available energy and amino acid digestibility of pigs and their applications in pig production.

The intestinal development of weaned piglets is incomplete, the function is not perfect, and the diarrhea symptoms are easy to occur, which affects the growth performance of piglets. Traditional Chinese veterinary medicine believe that piglets are weak in spleen and stomach, and are susceptible to cold, dampness and heat, resulting in spleen dysfunction, abnormal transmission of large and small intestine, and diarrhea. The traditional Chinese medicine (TCM) syndrome differentiation of diarrhea includes damp-heat accumulation, cold-dampness obstructing spleen, spleen qi deficiency and spleen deficiency and dampness. For different types, targeted prescriptions should be selected for syndrome differentiation and treatment. As the genuine medicinal materials in Hubei, the ten Chu medicines have the characteristics of excellent quality, large scale and good curative effect. Among them, Coptidis Rhizoma, Poria cocos, Atractylodis Rhizoma and Magnoliae Officinalis Cortex, as the representative drugs of the ten Chu medicines, have the effects of clearing heat and drying dampness, dispelling wind and dispelling cold, invigorating spleen and transporting dampness, and have a significant effect on improving piglet diarrhea. This paper systematically expounded the control effect and mechanism of four kinds of genuine medicinal materials in Hubei-Coptidis Rhizoma, Poria cocos, Atractylodis Rhizoma and Magnoliae Officinalis Cortex, on piglet’s diarrhea, as well as the application forms in actual production, so as to provide reference for the application of Hubei authentic medicinal materials in animal husbandry production.

Mitochondria plays a key role in energy metabolism, free radical generation and signal transduction in porcine intestinal epithelial cells. Recent studies have revealed that mitochondrial damage can induce apoptosis, thereby affecting the intestinal health of piglets. Given the significant roles of intestinal epithelial cells in the digestion and absorption of nutrients and maintenance of the intestinal barrier in piglets, it is of great value to get knowing the effects of mitochondrial damage-mediated apoptosis of intestinal epithelial cells on the intestinal health of piglets, and exploring regulatory options based on this target. This review elaborately explored the significant roles of mitochondrial damage and the apoptotic signals it induces on the intestinal health of piglets, and furtherly introduces nutritional and non-nutritional regulatory strategies, which aims to provide a scientific basis for exogenous intervention in the regulation of the intestinal health in piglets.

Plant polysaccharides (PPs) exhibit various biological activities such as antioxidant properties, immunomodulatory effects, and promotion of beneficial gut bacteria, and have been widely applied in livestock and poultry breeding. Although there is a wealth of research on the effects of plant polysaccharides on the production performance and meat quality of broiler chickens, a systematic review has not yet been formed. This paper summarizes the research hotspots of plant polysaccharides in broiler chicken farming both domestically and internationally, categorizing their impacts on broiler chickens into five major aspects: gut microbiota, antioxidant capacity, immune regulation, production performance, and meat quality. It also provides a preliminary analysis of the underlying mechanisms of action. The aim is to provide references for the development and application of plant polysaccharides in broiler production, so as to improve breeding efficiency.

In modern intensive farming systems, oxidative stress has become a key factor limiting production efficiency in poultry. Oxidative stress can disrupt the body’s redox balance and exert negative impacts on poultry production. By adding exogenous antioxidants to the diet, the body’s antioxidant capacity can be enhanced, and the redox homeostasis in poultry can be restored, thereby effectively addressing oxidative stress. This article introduces the effects and molecular mechanisms of antioxidants such as vitamins, carotenoids and polyphenols, and reviews their applications in improving production performance, meat quality, egg quality and reproductive performance in poultry. It is expected to provide references for the further development and utilization of antioxidant feed additives in poultry production.

With the upgrading of consumption and the optimization of dietary structure, mutton has gradually become an important choice for healthy eating due to its high-protein and low-fat nutritional characteristics. However, the characteristic odor of mutton has become a key factor restricting the growth of its consumption. 4-alkyl branched-chain fatty acids, 3-methylindole and 4-methylphenol are the main components of the mutton odor, and their formation mechanism is closely related to rumen microbial metabolism and lipid oxidation processes, etc. This article systematically reviews the sources of compounds with odor characteristics, elaborates on their influences on the mutton odor from the perspectives of genetic factors, feeding methods and diets, as well as gender and months of age, and analyzes the effective ways to reduce the mutton odor from the perspectives of breed hybridization, nutritional regulation and mutton processing, aiming to provide reference basis for improving the quality of mutton and promoting the high-quality development of the industry.

α-lactalbumin (α-La) and β-lactoglobulin (β-Lg) play important nutritional functions as the main components of bovine whey protein. In recent years, specialty livestock milks other than cow’s milk have been increasingly favored by consumers, and their active components and functions have been gradually studied. α-La and β-Lg, as important active proteins in milk, play nutritional roles in other livestock milk that should not be ignored. In this paper, we reviewed the content, structure and function of α-La and β-Lg in goat, sheep, yak, buffalo, horse, donkey and camel milks, and summarized the current assay methods of α-La and β-Lg in these seven types of livestock milks, with a view to providing theoretical references for the further functional research and differentiated development of different livestock milks.

Lactoferrin (LTF) is a multifunctional glycoprotein mainly present in milk. It can not only directly exert antioxidant effects by binding iron ions and other heavy metal ions to reduce the production of reactive oxygen species (ROS), but also activate the body’s endogenous antioxidant defense system by regulating redox-sensitive transcription factors, thereby promoting the expression of antioxidant enzymes and alleviating oxidative damage. This review summarizes the molecular biological characteristics of LTF, the mechanisms of its antioxidant and anti-inflammatory responses and its applications in livestock and poultry production, aiming to provide a theoretical reference for further clarifying the application mechanism of LTF in the prevention and treatment of oxidative damage.

Yeasts are a group of unicellular fungi, and yeast cell walls serve as a source of their active components. With β-glucan and mannan as the main active substances, they possess efficacy such as enhancing immunity and antioxidant activity, and are widely applied in fields like feed and aquaculture, demonstrating significant application value. In recent years, physical, chemical, and enzymatic modification methods have been employed to improve the water solubility and inherent biological activity of β-glucan and mannan, while reducing production costs, thus showing broad application potential. This article reviews the structure, modification methods, and biological activities of β-glucan and mannan from yeast cell walls, aiming to provide a reference for promoting in-depth research on yeast cell wall β-glucan and mannan and their scientific application in livestock and poultry production.

Flavonoids, as natural polyphenolic compounds, are important secondary metabolites in plants and are widely found in nature. This review provides a detailed overview of the bioactivity of flavonoids, including their antioxidant, antibacterial, antiviral, anticancer, anti-tumor, and immunomodulatory properties. The main extraction methods include solvent extraction, ultrasonic-assisted extraction, microwave-assisted extraction, supercritical fluid extraction, and enzymatic hydrolysis. The application value of flavonoids in animal husbandry is summarized, and the reference is provided for the research and development of efficient extraction process and functional feed additives of flavonoids.

As an essential macromineral element in animals, phosphorus is widely involved in the physiological processes of energy metabolism, bone development, and DNA synthesis. Phosphorus in plant feed mainly exists in the form of phytic phosphorus, accounting for 60% to 90% of the total phosphorus, and the utilization rate in monogastric animals is low. Phosphorus phytate easily binds to minerals (such as Ca, Fe and Zn) and proteins to form difficult complexes and affect the absorption and utilization efficiency of nutrients. In addition, unused phosphorus phytate is discharged with the feces of livestock and poultry, which may cause environmental problems such as eutrophication of water bodies. Therefore, this paper reviews the main ways and research status of the antitrophic mechanism of phytate and the improvement of phytate phosphorus utilization in recent years, aiming to provide a reference for improving the utilization rate of phytate phosphorus in feed in livestock and poultry during feeding.

Antibiotics were once widely used in the breeding process of China’s livestock industry. However, with the continuous increase in public attention to food safety, the ecological environment and other issues, a series of problems caused by the abuse of antibiotics have gradually emerged. Against this backdrop, China’s feed industry has entered an era of comprehensive prohibition of antibiotics, which poses a major challenge to the development of the livestock industry. Probiotics, as a highly promising feed additive, can regulate the structure of the intestinal microbiota, improve the intestinal barrier, and modulate the body’s immune response, demonstrating unique advantages and value. They are expected to replace antibiotics and play a role in livestock breeding. Enterococcus faecium belongs to the lactic acid bacteria group, has strong resistance to the environment and can reach the host’s intestine with a certain number of viable bacteria, thus receiving significant attention in the field of feed additives and showing broad application prospects. As a beneficial active microorganism, Enterococcus faecium can promote the absorption of nutrients, regulate the balance of the intestinal microbiota, enhance the function of the intestinal epithelial barrier, and improve the host’s antioxidant and immune capabilities. There has been an increasing number of studies on the impact of this bacterium on livestock and poultry. It has been shown to improve the performance, reduce the diarrhea rate and mortality rate, optimize the digestive function and feed utilization rate of various livestock and poultry such as pigs, cattle, sheep and chickens, thereby increasing the economic benefits of farms. Its application scope in the livestock industry is also constantly expanding. This article focuses on Enterococcus faecium and reviews its biological characteristics, action mechanisms, applications in the livestock industry, and current existing problems, aiming to provide a reference for subsequent research on this bacterium and to promote it to play a greater role in the livestock industry.

Heat stress is one of the most common environmental challenges worldwide, exerting various negative effects on the body of both humans and animals, particularly by inducing gastrointestinal symptoms. Existing research indicates that heat stress has complex and extensive impacts on intestinal tissue and gut microbiota, and modulating the gut microbiota may help alleviate heat stress responses. Gut microbiota modulation is expected to become a key intervention strategy for mitigating heat stress-related damage. This review summarized scientific evidence on the relationship between heat stress and the gut, including changes in intestinal barrier function, immune responses, metabolism, and gut microbiota under heat stress, as well as research progress on how gut microbiota regulates the body’s heat adaptation capacity.

Intact intestinal mucosal epithelium can effectively prevent the invasion of harmful microorganisms and is extremely important for animal health. Probiotics have functions such as promoting the regeneration and repair of intestinal epithelium, improving intestinal epithelial permeability and maintaining intestinal homeostasis, inhibiting pathogenic bacteria, adjusting the structure of intestinal microbiota, alleviating intestinal inflammation, and enhancing the performance of livestock and poultry. This article reviewed the research progress on the regeneration and repair of intestinal epithelium, the regulatory mechanism of probiotics on it, and the application of probiotics in livestock breeding, aiming to provide a reference for studying the regulation of intestinal health in livestock and poultry by probiotics.

This study aimed to investigate the effects of probiotics and synbiotics addition in sow-offspring’s diet on nutrient composition and expression of genes related to muscle development and lipid metabolism of offspring Bama mini-pigs. Sixty-four pregnant Bama mini-pigs with 3 to 5 parities were randomly divided into 4 groups, which were fed a basal diet (control group), diet supplemented with virginiamycin pure product (antibiotics group), diet supplemented with compound probiotics fermentation mixture (probiotics group) and diet supplemented with compound probiotics fermentation mixture+oligosaccharides (synbiotics group), respectively, each group contained 16 pigs. After delivery, the piglets were weaned at 28 days of age and two piglets from per litter were selected, the offspring were fed the same diet as their sows. At 65, 95 and 125 days of age, eight piglets per group were selected and the biceps femoris muscles were sampled to determine the nutrient composition and the expression of related genes. The results showed that compared with the control group, the contents of intramuscular fat, non-essential amino acids, flavor amino acids, total amino acids, alanine, aspartic acid, glutamic acid, glycine, serine and hexadecenoic acid at 65 days of age and content of proline at 95 days of age of probiotics group and synbiotics group were significantly increased (P<0.05); the contents of isoleucine and valine at 65 days of age of the antibiotics group were significantly increased (P<0.05), the mRNA relative expression level of adipose triglyceride lipase (ATGL) at 65 days of age was significantly increased (P<0.05), and the mRNA relative expression levels of lipoprotein lipase (LPL), stearoyl coenzyme A desaturase (SCD) and fatty acid binding protein 4 (FABP4) at 95 days of age were significantly decreased (P<0.05); the content of oleic acid (C18∶1n9c) at 125 days of age of the probiotics group was significantly increased (P<0.05), and the mRNA relative expression levels of myogenic factor 5 (Myf5), LPL and peroxisome proliferator activated receptor α (PPARα) at 65 days of age, the myosin heavy chain Ⅰ (MyHCⅠ) and myogenic factor 6 (Myf6) at 95 days of age and the Myf5, Myf6, acetyl coenzyme A carboxylase (ACC), fatty acid synthase (FASN) and peroxisome proliferator activated receptor γ (PPARγ) at 125 days of age were significantly increased (P<0.05); the contents of tetradecanoic acid, hexadecanoic acid, C18∶1n9c, monounsaturated fatty acids (MUFA) and n-3 polyunsaturated fatty acids/n-6 polyunsaturated fatty acids at 65 days of age of the synbiotics group were significantly increased (P<0.05), the content of intramuscular fat at 95 days of age was significantly increased (P<0.05), the mRNA relative expression levels of PPARγ at 95 days of age and Myf6, FASN, SCD, LPL, PPARα and PPARγ at 125 days of age were significantly increased (P<0.05), and the mRNA relative expression level of myostatin (MSTN) at 95 days of age was significantly decreased (P<0.05). In conclusion, the probiotics and synbiotics addition in sow-offspring’s diet can alter the composition of amino acids and fatty acids, and regulate the expression of genes related to myogenic factors and lipid metabolism in biceps femoris muscle of offspring, which are beneficial to improve the meat quality.

This experiment aimed to investigate the effects of pyrroloquinoline quinone (PQQ) on growth performance, antioxidant function and intestinal microbiota of weaned piglets. A total of 108 healthy “Duroc×Yorkshire×Landrace” weaned piglets aged (22±1) days with similar body weights, half male and half female, were randomly divided into 3 groups with 6 replicates per group and 6 piglets per replicate. Piglets in the control group were fed a basal diet, while those in the experimental groups were fed the basal diets supplemented with 4 and 8 mg/kg PQQ, respectively. The experimental period lasted for 28 days. The results showed that compared with the control group: 1) dietary supplementation with 4 and 8 mg/kg PQQ significantly increased the average daily gain during days 15 to 28 and days 1 to 28 (P<0.05), and significantly decreased the feed-to-gain ratio (P<0.05). 2) Dietary supplementation with 4 and 8 mg/kg PQQ significantly decreased the contents of pro-inflammatory cytokines interleukin-1β (IL-1β) and interleukin-6 (IL-6) in serum and liver (P<0.05); regarding oxidative damage indices, supplementation with 4 and 8 mg/kg PQQ significantly decreased the contents of reactive oxygen species (ROS) in serum, as well as malondialdehyde (MDA) and ROS in liver (P<0.05); for antioxidant indicators, supplementation with 4 and 8 mg/kg PQQ significantly increased the activities of catalase (CAT), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), glutathione S-transferase (GST) and γ-glutamylcysteine ligase (γ-GCL), the content of reduced glutathione (GSH), and total antioxidant capacity (T-AOC) in serum, as well as the activities of SOD and GST in liver (P<0.05). 3) Dietary supplementation with 8 mg/kg PQQ significantly increased the villus height to crypt depth ratio (V/C) in the duodenum and ileum (P<0.05), while supplementation with 4 mg/kg PQQ significantly increased the V/C in jejunum (P<0.05). 4) Dietary supplementation with 4 and 8 mg/kg PQQ significantly increased the contents of acetic acid, propionic acid, isobutyric acid, butyric acid and isovaleric acid in cecal contents (P<0.05). 5) Dietary supplementation with 4 and 8 mg/kg PQQ significantly decreased the relative abundances of Clostridium, Terrisporobacter and Blautia in cecum (P<0.05), and significantly increased the relative abundances of Prevotellaceae_NK3B31_group, norank_f_Prevotellaceae, UCG-002, Rikenellaceae_RC9_gut_group and NK4A214_group in cecum (P<0.05). In conclusion, PQQ can alleviate weaning stress in piglets by enhancing antioxidant capacity, improving intestinal morphology, promoting short-chain fatty acid production and optimizing intestinal microbiota structure. Based on the results of this study, it is recommended that the dietary supplementation level of PQQ for weaned piglets be 4 mg/kg.

This experiment aimed to optimize the vegetable waste fermentation process and investigate the feeding effects of the fermented vegetable waste in piglets. Vegetable waste fermentation optimization experiment: using vegetable waste as the raw material, a single-factor experimental design was used to examine the effects of fermentation substrate moisture content, compound bacteria addition, and fermentation time on crude protein content and crude fiber degradation rate. Based on the results of the single-factor experiments, response surface methodology was then applied to optimize the fermentation process, followed by validation of the optimized conditions. Feeding effect experiment of fermented vegetable waste in piglets: eighteen 42-day-old Duroc×Landrace×Yorkshire crossbred piglets with similar body weight and good health condition were selected and randomly divided into three groups, with three replicates per group and two piglets per replicate. The control group, trial group Ⅰ, and trial group Ⅱ were fed experimental diets supplemented with 0, 10% and 30% fermented vegetable waste, respectively. The feeding trial lasted for 37 days, including a 7-day adaptation period and a 30-day formal trial period. The results showed as follows: 1) the optimal fermentation process parameters were a fermentation substrate moisture content of 57% (with a mixture ratio of vegetable waste to auxiliary materials of 3∶1), a fermentation time of 20 days, and a compound bacteria addition rate of 2 g/kg. Under these optimized conditions, the crude protein content increased from 18.78% to 20.13%, while the crude fiber content decreased from 25.11% to 22.76%. 2) Compared with the control group, trial group Ⅰ showed a significantly lower diarrhea rate and serum triglyceride (TG) content (P<0.05), and an extremely significant reduction in the diarrhea index (P<0.01). No significant differences were observed in average daily gain (ADG), feed-to-gain ratio (F/G), body size indexes, and various serum indexes—including alanine aminotransferase (ALT) activity, as well as contents of creatinine (CREA), immunoglobulin M (IgM), complement 3 (C3), and complement 4 (C4)—between trial groups Ⅰ and Ⅱ compared with the control group (P>0.05). In trial group Ⅱ, serum albumin (ALB) and total cholesterol (TC) contents, as well as aspartate aminotransferase (AST) activity, were extremely significantly lower than those in the control group (P<0.01), while serum alkaline phosphatase (ALP) activity was also significantly reduced (P<0.05). In contrast, the average daily feed intake (ADFI) in trial group Ⅱ was extremely significantly higher than that in the control group (P<0.01). Additionally, serum urea (UREA) and immunoglobulin G (IgG) contents in the trial groups Ⅰ and Ⅱ were extremely significantly decreased (P<0.01), along with serum glucose (GLU) content was extremely significantly increased compared with the control group (P<0.01). In summary, the fermentation parameters optimized by response surface methodology can effectively enhance the nutritional value of vegetable waste. The substitution of basal diet with fermented vegetable waste does not exert any adverse effects on the growth performance, body size indexes and immune function of piglets. Taking into comprehensive consideration indicators such as diarrhea rate, replacing 10% of the basal diet with fermented vegetable waste yields the optimal results.

This experiment aimed to investigate the effects of dietary supplementation with composite functional bioactive agent on reproductive performance, physiological metabolism and immune function of sows under high-temperature stress during late gestation and lactation. A total of 360 healthy crossbred (Landrace×Yorkshire) pregnant sows with consistent genetic background, similar backfat thickness [(17.54±0.18) mm] and parity [(4.47±0.18) parities] were randomly divided into 2 groups with 180 replicates per group and 1 sow per replicate. The control group was fed a basal diet, while the experimental group was fed the basal diet supplemented with composite functional bioactive agent (300 mg/kg resveratrol+200 mg/kg baicalein+10 000 mg/kg taurine, added via premix formulation). The experiment lasted from day 90 of gestation to day 21 of lactation (weaning). The results showed that compared with the control group: 1) dietary supplementation with composite functional bioactive agent extremely significantly increased the litter size, number of healthy piglets and litter weight at birth (P<0.01), extremely significantly decreased the average daily feed intake of sows during lactation (P<0.01), significantly reduced the weaning backfat thickness of sows (P<0.05), and tended to increase the average daily gain of piglets (P=0.098) and weaning litter weight (P=0.091); 2) dietary supplementation with composite functional bioactive agent extremely significantly increased the serum taurine content of sows at weaning (P<0.01), significantly decreased the serum glycine content (P<0.05), and tended to increase the serum valine content (P=0.083); 3) dietary supplementation with composite functional bioactive agent significantly improved the serum total antioxidant capacity of sows at weaning (P<0.05), and tended to increase the serum total protein content (P=0.062); 4) dietary supplementation with composite functional bioactive agent tended to decrease the immunoglobulin M content in colostrum (P=0.089) and tended to increase the secretory immunoglobulin A (sIgA) content in milk (P=0.064); 5) dietary supplementation with composite functional bioactive agent affected the metabolite composition of serum and milk. Among them, the differential metabolite 3-methyl-2-oxovaleric acid in milk was significantly up-regulated (P<0.05), which was enriched in the valine, leucine, and isoleucine biosynthesis and degradation pathway, and showed an extremely significant positive correlation with the sIgA content in milk (P<0.01). In conclusion, dietary supplementation with composite functional bioactive agent during late gestation and lactation can improve the reproductive performance of sows under high-temperature stress, enhance the antioxidant capacity to a certain extent, and increase the sIgA content in milk.

The purpose of this experiment was to investigate the effects of varying levels of crude protein (CP) and standard ileal digestible amino acids (SID AAs) in diversified diets on growth performance, nutrient apparent digestibilities, nitrogen balance and fecal microbiota in growing pigs, and to determine the optimal CP and SID AAs levels in diversified diets. Seventy-two Duroc×Landrace×Yorkshire crossbred pigs, with an average body weight of (25.41±1.93) kg, were randomly assigned to six groups, with six replicates per group and two pigs per replicate. The dietary treatments consisted of three CP levels (16%, 15% and 14%) paired with SID AAs levels at 100.0% of NRC (2012) recommendations, and three SID AAs levels [75.0%, 87.5% and 112.5% of NRC (2012) recommendations] with a constant CP level of 14%. The experimental period included a 30-day feeding trial followed by a 7-day nitrogen balance trial. The results showed as follows: 1) under consistent dietary SID AAs levels, different CP levels did not significantly affect the growth performance (P>0.05). However, the apparent digestibilities of dry matter (DM), gross energy (GE) and CP were significantly lower in 16% CP group compared to the other two groups (P<0.05). At dietary CP level of 14%, increasing SID AAs levels resulted in significant linear and quadratic changes in average daily gain (ADG), feed to gain ratio (F/G) as well as apparent digestibilities of DM, GE, ether extract (EE) and CP (P<0.05). Furthermore, the apparent digestibilities of DM, GE, EE and CP were significantly lower in 75.0% NRC group compared to 100.0% and 112.5% NRC groups (P<0.05). 2) As dietary CP level decreased, the fecal nitrogen excretion was significantly decreased (P<0.05); the nitrogen deposition rate and apparent biological value of nitrogen in 14% CP group were significantly higher than those in 15% and 16% CP groups (P<0.05); the serum urea nitrogen content in 16% CP group was significantly higher than that in 14% and 15% CP groups (P<0.05). At dietary CP level of 14%, increasing SID AAs levels resulted in quadratic changes both in nitrogen deposition rate and apparent biological value of nitrogen (P<0.05), and the serum albumin content was increased linearly (P<0.05). 3) The fecal microbiota analysis revealed that dietary CP and SID AAs levels did not significantly influence α and β diversity (P>0.05). However, at dietary CP level of 14%, the relative abundances of Bacteroidetes and unclassified Veillonellaceae in 100.0% NRC group were significantly higher compared to 75.0% NRC group (P<0.05). In conclusion, under the conditions of this experiment, based on evaluations of growth performance, nutrient apparent digestibility and nitrogen balance related parameters, the optimal dietary CP level for 25 to 50 kg growing pigs was determined to be approximately 14% in a diversified diet. At this CP level, the appropriate SID AAs levels were identified as follows: when using ADG and EE apparent digestibility as indicators, the optimal SID AAs levels ranged from 103.46% to 105.06% of NRC (2012) recommendations; when considering F/G, nitrogen deposition rate, and apparent biological value of nitrogen as indicators, the optimal SID AAs levels ranged from 98.50% to 101.92% of NRC (2012) recommendations. The overall average optimal SID AAs level was approximately 101.65% of NRC (2012) recommendations.

This study aimed to investigate the regulatory effects of glutamine supplementation in drinking water on the physiological functions of chicks under acute cold stress by examining its impacts on body temperature, fecal traits, and serum biochemical indicators. Forty 1-day-old Hy-Line brown chicks were randomly divided into five groups: thermoneutral control group (TN group), acute cold stress treatment group (ACS group), acute cold stress+4 g/L glutamine in drinking water group (ACS+4Gln group), acute cold stress+8 g/L glutamine in drinking water group (ACS+8Gln group), and acute cold stress+12 g/L glutamine in drinking water group (ACS+12Gln group), with eight chicks per group. All chicks were reared in cages with ad libitum access to a basal diet under controlled environmental conditions (room temperature: 33 to 35 ℃; relative humidity: 65% to 70%). At 6 to 7 days of age, chicks in the ACS, ACS+4Gln, ACS+8Gln, and ACS+12Gln groups were exposed to a low-temperature environment (room temperature: 12 ℃; relative humidity: 65%) for 12 hours to induce acute cold stress. After the stress period, body temperature was measured, and fecal and blood samples were collected for the analysis of fecal traits and serum biochemical indicators. The results showed that acute cold stress extremely significantly decreased the body temperature of chicks (P<0.01), and induced significant or ex-tremely significant changes in fecal color, moisture content, and most serum biochemical indicators (P<0.05 or P<0.01). Supplementation with 8 to 12 g/L glutamine in drinking water effectively alleviated the adverse effects of acute cold stress, as evidenced by the recovery of body temperature, reduced fecal moisture content, improved fecal color, and an overall positive trend in serum bio-chemical indicators. Specifically, in terms of serum protein metabolism-related indicators, the contents of total protein (TP) and albumin (ALB) were significantly or extremely significantly increased (P<0.05 or P<0.01). Regarding serum indicators related to hepatic, pancreatic, and renal functions, the abnormally elevated contents or activities of total bilirubin (TB), total bile acid (TBA), γ-glutamyl transferase (GGT), aspartate aminotransferase (AST), alanine aminotransferase (ALT), amylase (AMY), lipase (LPS), creatinine (Crea), and uric acid (UA) were significantly or extremely significantly suppressed (P<0.05 or P<0.01). In terms of serum glucose and lipid me-tabolism-related indicators, the contents of glucose (GLU), total cholesterol (TC), and triglycerides (TG) also showed significant or extremely significant decreases (P<0.05 or P<0.01). In conclusion, supplementation with 8 to 12 g/L glutamine in drinking water can mitigate the negative effects of acute cold stress on chicks’ physiological functions through multiple pathways.

This experiment was conducted to study the effects of metabolizable energy (ME) intake during growing period on growth and development, sexual maturity and early egg weight of laying hens during 7 to 24 weeks of age. A total of 540 six-week-old Hy-Line brown laying hens were randomly divided into 3 groups with 6 replicates in each group and 30 hens in each replicate. During 7 to 15 weeks of age, the dietary ME levels of the control group, 90% ME group and 80% ME group were 12.34, 11.11 and 9.87 MJ/kg, respectively, and other nutrient levels were the same. During 16 to 24 weeks of age, the laying hens in each group were fed the same diet freely. The experiment lasted for 18 weeks. The results showed as follows: 1) with the decreased of ME intake during 7 to 15 weeks of age, the average daily gain (ADG) during 7 to 12 weeks of age and 13 to 15 weeks of age was significantly linearly decreased (P<0.05), and the feed to weight ratio (F/G) was significantly linearly increased (P<0.05); the average daily feed intake (ADFI) and average daily metabolizable energy intake (ADMEI) during 16 to 18 weeks of age were significantly linearly increased (P<0.05); the ADG during 16 to 18 weeks of age and 19 to 24 weeks of age was significantly linearly increased (P<0.05), and the F/G was significantly linearly decreased (P<0.05); the ADMEI during 7 to 24 weeks of age and metabolizable energy conversion ratio (MECR) during 7 to 12 weeks of age, 16 to 18 of age, 19 to 24 weeks of age and 7 to 24 weeks of age were significantly linearly decreased (P<0.05). 2) With the decreased of ME intake during 7 to 15 weeks of age, the body weight at 9, 12, 14, 15, 16 and 17 weeks of age was significantly linearly decreased (P<0.05), but the body weight at 23 weeks of age was significantly linearly increased (P<0.05); the body weight coefficient of variation (CV) at 12, 14, 15, 17, 18, 23 and 24 weeks of age was significantly linearly decreased (P<0.05). 3) With the decreased of ME intake during 7 to 15 weeks of age, the length to weight ratios of femur, tibia and tarsus, and the indices of femur and tibia at 15 weeks of age were significantly linearly increased (P<0.05), and the abdominal fat rate was significantly linearly decreased (P<0.05); the abdominal fat rate at 18 weeks of age were increased and then decreased in a quadratic curve (P<0.05), the length, weight, length to weight ratios and indices of oviduct were significantly linearly decreased (P<0.05). 4) With the decreased of ME intake during 7 to 15 weeks of age, the age at onset of lay, age at 50% laying rate, weight of first eggs, weight of first three eggs and weight of first seven eggs were significantly linearly increased (P<0.05). The proportion of eggs which egg weight <46 g and 46 to 50 g during 19 to 24 weeks of age of 80% ME group were significantly lower than than those of the control group (P<0.05), and the proportion of egg which egg weight weight>60 g of 80% ME group was significantly higher than that of the control group (P<0.05). In conclusion, during 7 to 15 weeks of age, the 90% or 80% ME intake affect the body weight of laying hens, but this effect disappears after 3 weeks of free feeding (18 weeks of age), and improve the group uniformity of laying hens, reduce the ADMEI during 7 to 15 weeks of age, and improve MECR; the 90% or 80% ME intake improve the skeletal development of laying hens at 15 weeks of age, but has no adverse effect on the development of carcass, internal organs and bones at 18 weeks of age; the 80% ME intake delay the development of reproductive organs and sexual maturity, but improve the early egg weight. Among them, the laying hens in 80% ME group show better performance in terms of MECR, growth and development, group uniformity and early egg weight.

This experiment was conducted to investigate the effects of dietary curcumin cocrystals on laying rate, egg quality and lipid metabolism of hyperlipidemia laying hens during late laying period. Thirty-two 60-week-old hyperlipidemia Hy-Line brown laying hens were randomly divided into 2 groups with 16 hens in each group. The control group was fed a basal diet, and the experimental group was fed a basal diet supplemented with 25 mg/kg curcumin cocrystals. The experiment lasted for 4 weeks. The results showed that compared with the control group: 1) dietary curcumin cocrystals significantly increased the laying rate at week 2 and week 4 (P<0.05); 2) dietary curcumin cocrystals significantly decreased the serum aspartate aminotransferase activity at week 2 (P<0.05), and significantly decreased the serum triglycerides, total cholesterol contents and aspartate aminotransferase, alanine aminotransferase activities at week 4 (P<0.05); 3) dietary curcumin cocrystals significantly decreased the liver weight and liver index (P<0.05), and significantly decreased the liver pathology scoring and triglycerides, low density lipoprotein cholesterol contents (P<0.05); 4) dietary curcumin cocrystals significantly increased the liver peroxisome proliferator activated receptor α (PPARα) mRNA relative expression level (P<0.05), and significantly decreased the liver sterol regulatory element-binding protein-1c (SREBP-1c) mRNA relative expression level (P<0.05). In conclusion, dietary supplemented with 25 mg/kg curcumin cocrystals can improve the laying rate and lipid metabolism of hyperlipidemia laying hens during late laying period.

This study aimed to evaluate the effects of in ovo feeding of leucine (Leu) on hatching performance, organ indexes and myofiber indices, myogenesis related genes expression and metabolome in pectoralis major muscle of Arbor Acres (AA) broilers during embryonic stage. Following a pre-trial to determine the optimal embryonic age and dosage for injection, a formal trial was conducted. A total of 288 embryos of AA broilers were randomly divided into 3 groups with 8 replicates per group and 12 embryos per replicate. The injection experiment was conducted at 6 embryonic days, the negative control (NC) group received no injection, the positive control (PC) group was injected with 200 μL of 0.9% sodium chloride (NaCl) solution, and the Leu group was injected with 200 μL 4.0 mg/mL Leu solution. The results showed as follows: 1) the optimal injection embryonic age for in ovo feeding of Leu was at 6 embryonic days, and the optimal injection dosage was 200 μL 4.0 mg/mL Leu solution. 2) The breast muscle weight and breast muscle rate at 15, 17 and 19 embryonic days of the Leu group were significantly higher than those of NC group and PC group (P<0.05), the femur wight, tibia weight, jejunum weight and jejunum index at hatch were significantly higher than those of NC group and PC group (P<0.05), and the cross-sectional area of myofiber and diameter of myofiber in pectoralis major muscle at 19 embryonic days were significantly higher than those of NC group and PC group (P<0.05). 3) The mRNA relative expression levels of mammal target of rapamycin complex 1 (mTORC1), ribosomal P70S6 kinase (P70S6K), and peroxisome proliferator activated receptor γ coactivator 1α (PGC1α) in pectoralis major muscle at 15 embryonic days of the Leu group were significantly higher than those of NC group and PC group (P<0.05), the mRNA relative expression level of myogenin (MyoG) in pectoralis major muscle at 15 embryonic days was significantly higher than that of NC group and PC group (P<0.05), the mRNA relative expression levels of MyoG and myogenic regulatory factors 4 (MRF4) in pectoralis major muscle at hatch were significantly higher than those of NC group and PC group (P<0.05), and the mRNA relative expression level of myostatin (MSTN) in pectoralis major muscle at 15 embryonic days was significantly lower than that of the NC group (P<0.05). 4) Compared with the NC group, the relative abundances of threonine (Thr)-Leu-tyrosine (Tyr), phosphocreatine (PCr) and histidine (His) et al in pectoralis major muscle of the Leu group were significantly up-regulated (P<0.05), while the relative abundances of S-adenosylmethionine (SAM), glutamic acid (Glu) and methionine (Met) et al were significantly down-regulated (P<0.05). Furthermore, the in ovo feeding of Leu changed the pathways, including nucleotide metabolism, sulfur metabolism, pentose phosphate pathway, histidine metabolism, glycerophospholipid metabolism, cysteine and methionine metabolism, arginine and proline metabolism, as well as apoptosis and necroptosis et al. In conclusion, the in ovo feeding of Leu during the early embryonic stage promote the protein synthesis and cell proliferation and differentiation in pectoral muscle, change the amino acid and nucleotide metabolism in skeletal muscle, which is beneficial to skeletal muscle development.

This experiment was conducted to investigate the effects of dietary crude protein level on growth performance, protein deposition, liver protein metabolism and cecal microbiota of medium-growing yellow-feathered broilers aged from 1 to 30 days, in order to determine their dietary crude protein requirements. A total of 900 one-day-old healthy female medium-growing yellow-feathered broilers with similar body weight were selected and randomly divided into 5 groups, with 6 replicates in each group and 30 chickens in each replicate. The dietary crude protein levels of each group were 18.00%, 19.00%, 20.00%, 21.00% and 22.00%, respectively. The experiment lasted for 30 d. The results showed as follows: 1) with the increase of dietary crude protein level, the body weight at 30 days of age, average daily gain, feed to gain ratio and protein deposition rate of broilers all showed linear and quadratic changes (P<0.05), and the daily protein deposition showed a quadratic change (P<0.05). The body weight at 30 days of age and average daily gain in 21.00% crude protein group was the highest, and the feed to gain ratio was the lowest. The protein deposition rate in 19.00% crude protein group was significantly higher than that in the other groups (P<0.05), while that in 22.00% crude protein group was significantly lower than that in the other groups (P<0.05). 2) With the increase of dietary crude protein level, the plasma globulin (GLB) content and liver aspartate aminotransferase to alanine aminotransferase ratio (AST/ALT) of broilers both showed quadratic changes (P<0.05), the plasma albumin to globulin (ALB/GLB) ratio showed linear and quadratic changes (P<0.05), and the liver glutamate dehydrogenase (GDH) content showed a quadratic change (P<0.05). Compared with 18.00% crude protein group, the plasma GLB content and liver AST/ALT and insulin-like growth factor-1 (IGF-1) content in 20.00% crude protein group were significantly increased (P<0.05), while the plasma ALB/GLB and liver GDH content in 20.00% and 21.00% crude protein groups were significantly decreased (P<0.05). 3) Compared with 18.00% crude protein group, the mRNA relative expression levels of IGF-1, mammalian target of rapamycin (mTOR), ribosomal protein S6 kinase 1 (S6K1), and eukaryotic translation initiation factor 4E-binding protein 1 (4EBP1) in liver of broilers in 20.00% crude protein group were significantly increased (P<0.05). 4) Compared with 18.00% crude protein group, the relative abundances of Bacteroides and Faecalibacterium in cecum of broilers in 20.00% and 22.00% crude protein groups were increased, while the Barnesiella relative abundance in cecum was decreased. In conclusion, 20.00% dietary crude protein level can effectively improve the growth performance, protein deposition and cecal microbiota structure of medium-growing yellow-feathered broilers. Taking average daily gain, feed to gain ratio, daily protein deposition and protein deposition rate as effect indicators, it is estimated through the dose-effect quadratic regression equation that the appropriate levels of dietary crude protein for female medium-growing yellow-feathered broilers aged from 1 to 30 days are 20.74%, 20.51%, 20.34% and 19.27%, and the daily crude protein requirements are 8.05, 7.96, 7.77 and 7.21 g/d, respectively.

This experiment was conducted to investigate the effects of α-lipoic acid (ALA) on muscle quality, textural characteristics, antioxidant capacity and muscle fiber types in white-feathered broilers. A total of 180 one-day-old healthy Arbor Acres (AA) broiler chicks with similar body weight were selected and randomly divided into 3 groups, with 6 replicates per group and 10 birds per replicate. The control group was fed a basal diet, while test groups Ⅰ and Ⅱwere supplemented with 100 and 300 mg/kg ALA in the basal diet, respectively. The trial lasted for 42 days. The results showed as follows: 1) compared with the control group, dietary supplementation with 100 and 300 mg/kg ALA significantly reduced drip loss, shear force, and yellowness (b^*) value of the breast muscle (P<0.05); dietary supplementation with 100 mg/kg ALA significantly increased the adhesiveness of breast and thigh muscles as well as the redness (a^*) value of breast muscle (P<0.05); dietary supplementation with 300 mg/kg ALA significantly decreased the lightness (L^*) value of breast muscle and the shear force of thigh muscle (P<0.05), significantly improved the gumminess and chewiness of breast muscle (P<0.05), and significantly reduced the hydroxyproline (Hyp) content in breast muscle (P<0.05). 2) Dietary supplementation with different levels of ALA had no significant effects on the common nutritional component contents in breast and thigh muscles (P>0.05). 3) Compared with the control group, dietary supplementation with 100 and 300 mg/kg ALA significantly increased the glutathione peroxidase (GSH-Px) activity in both breast and thigh muscles (P<0.05), as well as the superoxide dismutase (SOD) activity in thigh muscle (P<0.05), while significantly reduced the malondialdehyde (MDA) content in thigh muscle (P<0.05). 4) Compared with the control group, dietary supplementation with 100 and 300 mg/kg ALA significantly upregulated the mRNA relative expression levels of myosin heavy chain Ⅰ (MyHC Ⅰ) and myosin heavy chain Ⅱa (MyHC Ⅱa) in breast muscle (P<0.05). Additionally, dietary supplementation with 100 mg/kg ALA significantly downregulated the mRNA relative expression level of myosin heavy chain Ⅱb (MyHC Ⅱb) in breast muscle (P<0.05). 5) Compared with the control group, dietary supplementation with 100 mg/kg ALA significantly up-regulated the mRNA relative expression levels of AMP-activated protein kinase (AMPK)α1, AMPKα2, sirtuin 1 (SIRT1), peroxisome proliferator-activated receptor-gamma coactivator-1α (PGC-1α), nuclear respiratory factor 1 (NRF1), and myocyte enhancer factor 2 (MEF2) in breast muscle (P<0.05); dietary supplementation with 300 mg/kg ALA significantly up-regulated the mRNA relative expression levels of AMPKα1, AMPKα2, SIRT1, and PGC-1α in breast muscle (P<0.05), while significantly down-regulated the mRNA relative expression level of AMPKγ3 in breast muscle (P<0.05). It is concluded that ALA can improve the muscle quality of white-feathered broiler by modifying textural characteristics, reducing collagen deposition, enhancing antioxidant capacity, upregulating expression of key genes in the AMPK/SIRT1/PGC-1α signaling pathway, and promoting the transition from glycolytic to oxidative muscle fiber types. Considering both the efficacy and cost-effectiveness, the addition of 100 mg/kg ALA to the diet of white-feathered broilers is recommended.

This experiment was conducted to investigate the effects of all-trans retinoic acid (ATRA) on intestinal and hepatic health of broilers stimulated by lipopolysaccharide (LPS). A total of 144 one-day-old healthy Arbor Acres Plus (AA⁺) broilers with similar initial body weight were randomly divided into 2 groups, fed with basal diet supplemented with 0 and 0.5 mg/kg ATRA, respectively. Each group had 6 replicates with 12 broilers per replicate (half male and half female). On 36 days of age, 4 broilers with body weight close to the average weight of each replicate (48 broilers in total) were selected. LPS stimulation was performed on 36, 38, 40 and 42 days of age: 2 broilers (1 male and 1 female) in each replicate were intraperitoneally injected with 1 mg/kg BW LPS, and the other 2 broilers (1 male and 1 female) were intraperitoneally injected with the same volume of sterile normal saline. According to the presence or absence of ATRA supplementation and LPS stimulation, the broilers were divided into 4 groups: CON group (basal diet+sterile normal saline), ATRA group (ATRA-supplemented diet+sterile normal saline), LPS group (basal diet+LPS stimulation) and ATRA+LPS group (ATRA-supplemented diet+LPS stimulation). All broilers were slaughtered for sample collection 3 hours after the last LPS stimulation on 42 days of age. The results showed as follows: 1) dietary ATRA supplementation had no significant effects on the growth performance of broilers from 1 to 21 days, 22 to 35 days and 1 to 35 days of age (P>0.05). 2) The spleen index of the LPS group was significantly higher than that of the CON group (P<0.05), and the spleen index of the ATRA+LPS group was significantly lower than that of the LPS group (P<0.05). 3) Dietary ATRA supplementation significantly decreased the duodenal villus height (VH) and crypt depth (CD) (P<0.05). The jejunal CD of the LPS group was significantly lower than that of the CON group (P<0.05), and the jejunal CD of the ATRA+LPS group was significantly higher than that of the LPS group (P<0.05). 4) The mRNA relative expression level of jejunal Mucin2 in the ATRA group was significantly higher than that in the other 3 groups (P<0.05). 5) LPS stimulation significantly increased the mRNA relative expression levels of interleukin-8 (IL-8), tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) in liver (P<0.05), and significantly decreased the mRNA relative expression level of interferon-γ (IFN-γ) in liver (P<0.05). Dietary ATRA supplementation significantly increased the mRNA relative expression levels of nuclear factor-κB (NF-κB), transforming growth factor-β4 (TGF-β4), B-cell lymphoma-2 associated X protein (BAX), B-cell lymphoma-2 (BCL-2), matrix metalloproteinase 9 (MMP9), heat shock protein 70 (HSP70), retinoic acid receptor α (RARα), retinoic acid receptor β (RARβ), retinoic acid receptor γ (RARγ), retinoid X receptor α (RXRα) and retinoid X receptor γ (RXRγ) in liver (P<0.05). The mRNA relative expression level of liver retinol dehydrogenase 10 (RDH10) in the LPS group was significantly higher than that in the other 3 groups (P<0.05), and the mRNA relative expression level of liver retinaldehyde dehydrogenase 2 (RALDH2) in the ATRA group was significantly higher than that in the other 3 groups (P<0.05). Compared with the CON group and LPS group, the mRNA relative expression level of liver RARγ in the ATRA group and ATRA+LPS group was significantly increased (P<0.05). In conclusion, dietary supplementation with 0.5 mg/kg ATRA can alleviate LPS-induced inflammatory responses in liver and spleen of broilers, and improve intestinal mucosal immunity by promoting jejunal Mucin2 expression, but it has no obvious alleviating effect on intestinal barrier and mucus layer damage caused by LPS stimulation. Meanwhile, ATRA can regulate retinoic acid metabolism, and these effects are speculated to be achieved by regulating the RAR/RXR signaling pathway.

This study was conducted to investigate the effects of dietary corn starch sugar residue supplementation on growth and development, plasma biochemical parameters and breast muscle quality of Pekin ducks. A total of 240 one-day-old male Pekin ducks with similar initial body weight [(56.51±0.08) g] were randomly divided into five groups with eight replicates per group and six ducks per replicate. Ducks in each group were fed diets supplemented with 0 (control), 5%, 10%, 15% and 20% corn starch sugar residue, respectively. The experimental period was 42 days. The results showed as follows: 1) compared with the control group, dietary supplementation with 15% and 20% corn starch sugar residue significantly reduced average body weight (ABW) at 21 days of age and average daily gain (ADG) from 1 to 21 days of age (P<0.05). Dietary supplementation with 20% corn starch sugar residue significantly increased feed-to-gain ratio (F/G) from 1 to 21 days of age and significantly decreased ABW at 42 days of age (P<0.05). As the dietary supplemental level of corn starch sugar residue increased, ABW at 21 days of age, ADG and F/G from 1 to 21 days of age, and ABW at 42 days of age all exhibited significant linear trends (P<0.05). 2) Compared with the control group, dietary supplementation with 5%, 10%, 15% and 20% corn starch sugar residue significantly decreased breast muscle rate of Pekin ducks (P<0.05), and showed significant linear and quadratic trends (P<0.05). Dietary supplementation with 5%, 10% and 20% corn starch sugar residue significantly increased the pancreatic index and gizzard index (P<0.05). Dietary supplementation with 5%, 15% and 20% corn starch sugar residue significantly increased duodenum index (P<0.05), and showed a significant linear trend (P<0.05). Dietary supplementation with 10% and 20% corn starch sugar residue significantly increased ileum index (P<0.05). 3) Compared with the control group, dietary supplementation with 5%, 15% and 20% corn starch sugar residue significantly decreased plasma lactate dehydrogenase (LDH) activity in Pekin ducks (P<0.05). Regression analysis indicated that as the dietary corn starch sugar residue supplemental level increased, plasma glucose (GLU) and total protein (TP) contents showed significant linear increasing trends (P<0.05). 4) Compared with the control group, dietary supplementation with 10% and 15% corn starch sugar residue significantly increased breast muscle lightness (L^*) value and significantly decreased the redness (a^*) value (P<0.05). 5) Compared with the control group, dietary supplementation with 10% and 15% corn starch sugar residue significantly decreased jejunal crypt depth in Pekin ducks (P<0.05). In conclusion, dietary supplementation with an appropriate supplemental level of corn starch sugar residue is beneficial for the development of digestive organs and improves plasma biochemical parameters in Pekin ducks, but it has negative effects on breast muscle rate and meat color.

This experiment was conducted to compare the growth performance and digestive organ indices among different breeds of semi-Muscovy ducks, and analyzed the correlations between the growth performance and digestive organ indices, to provide a scientific basis for optimizing maternal breed selection in production for semi-Muscovy ducks. Four breeds of 1-day-old semi-Muscovy ducks, derived from maternal lines of Guiliu M18, Clima M18, Zhongxu Changbai and Kefeng Yunpin were selected as experimental subjects, a total of 600 ducks were allocated into 8 groups according to breed and sex, with each breed contained 1 male duck group and 1 female duck group, each group contained 5 replicates with 15 ducks per replicate. The experiment lasted for 70 days. The results showed as follows: 1) the body weight at 70 days of age of Guiliu M18 semi-Muscovy male ducks was significantly higher than that of Zhongxu Changbai semi-Muscovy male ducks (P<0.05), and the feed-to-gain ratio was significantly lower than that of Clima M18 semi-Muscovy male ducks (P<0.05). The feed intake of Guiliu M18 and Clima M18 semi-Muscovy female ducks was significantly lower than that of Zhongxu Changbai and Kefeng Yunpin semi-Muscovy female ducks (P<0.05), and the feed-to-gain ratio of Guiliu M18 semi-Muscovy female ducks was significantly lower than that of Zhongxu Changbai semi-Muscovy female ducks (P<0.05). 2) The rectum index of Zhongxu Changbai semi-Muscovy male ducks was significantly lower than that of Clima M18 semi-Muscovy male ducks (P<0.05). The gizzard index of Guiliu M18 semi-Muscovy female ducks was significantly higher than that of Zhongxu Changbai and Kefeng Yunpin semi-Muscovy female ducks (P<0.05), and the duodenum index was significantly higher than that of the other breed semi-Muscovy female ducks (P<0.05). 3) The growth performance and digestive organ indices of 4 breeds of semi-Muscovy duck showed different correlations. In summary, under the conditions of this experiment, different breeds of semi-Muscovy ducks exhibit varying degrees of differences in growth performance and digestive organ indices, and the correlations between the growth performance and digestive organ indices are not completely consistent. The Guiliu M18 semi-Muscovy ducks show a lower feed-to-gain ratio, making it more suitable as the maternal line in production for semi-Muscovy ducks.

This experiment was conducted to investigate the effects of dietary phytosterol supplementation on laying performance, egg quality, reproductive organs and lipid metabolism of laying ducks at different laying stages. A 2×2 two-factor completely randomized design was adopted, with the experimental factors being duck days of age and dietary phytosterol supplementation levels. A total of 264 healthy Longyanshan Ma ducks, comprising 132 ducks at 210 days of age (peak laying phase) and 132 ducks at 820 days of age (late laying phase), were randomly divided into 2 groups, respectively, and 4 groups as total, with 6 replicates per group and 11 ducks per replicate. Two experimental diets were prepared by supplementing the basal diet with 0 or 15 mg/kg phytosterols. The trial lasted for 9 weeks. The results showed as follows: 1) compared with the basal diet, dietary supplemented with 15 mg/kg phytosterols significantly increased albumen height, Haugh unit, and the relative weight of >6 to 8 mm follicles (P<0.05), and significantly decreased plasma levels of total cholesterol (T-CHO) and high-density lipoprotein cholesterol (HDL-C), as well as alkaline phosphatase (AKP) activity (P<0.05). 2) Compared with 210-day-old ducks, 820-day-old ducks had significantly lower average daily feed intake, laying rate, daily egg weight, eggshell strength, albumen height, Haugh unit, eggshell toughness, eggshell relative weight, number of >8 mm follicles, and hepatic dry matter and ether extract levels (on both dry matter and fresh weight basis) (P<0.05), and had significantly higher egg weight, feed to egg ratio, yolk color, relative weight of >6 to 8 mm follicles, and plasma T-CHO and low-density lipoprotein cholesterol (LDL-C) levels (P<0.05). 3) For the 820-day-old ducks fed the diet supplemented with 15 mg/kg phytosterols, the relative weight and number of >6 to 8 mm follicles were significantly higher than those in the other three groups (P<0.05), while the Haugh unit, eggshell thickness, number of >8 mm follicles, and ratio of vacuoles to lipid droplets in hepatic tissue did not differ significantly from those in the 210-day-old ducks fed the basal diet (P>0.05). In conclusion, phytosterols help suppress the increase in the ratio of vacuoles to lipid droplets in hepatic tissue in peak-laying ducks. Dietary supplementation with 15 mg/kg phytosterols in late-laying ducks can improve egg quality and promote the development of >6 to 8 mm follicles.

This experiment was conducted to investigate the effects of different zinc sources [zinc sulfate (ZnSO₄), zinc protein (Zn-Pro), zinc methionine (Zn-Met) and zinc glycine (Zn-Gly)] on performance and serum reproductive hormone, antioxidant, biochemical indices of breeding geese during laying period. A total of 120 thirty-four-week-old breeding geese during laying period with similar body condition were randomly divided into 4 groups with 6 replicates in each group and 5 geese in each replicate (1 male and 4 females). Geese in 4 groups were fed basal diets supplemented with zinc sulfate (control group), zinc protein (zinc protein group), zinc methionine (zinc methionine group) and zinc glycine (zinc glycine group), respectively, and dietary zinc additive amounts were all 65 mg/kg (calculated as zinc). The pre-experimental period lasted for 1 week, and the experimental period lasted for 16 weeks. The results showed as follows: 1) compared to the control group, the laying rate of zinc methionine group and zinc glycine group was significantly increased (P<0.05), and the feed-to-egg ratio of zinc methionine group was significantly decreased (P<0.05). 2) Compared to the control group, the serum estradiol content of zinc methionine group was significantly increased (P<0.05). The serum luteinizing hormone content of zinc methionine group was significantly higher than that of zinc protein group (P<0.05), and the serum estradiol content of zinc methionine group and zinc glycine group was significantly higher than that of zinc protein group (P<0.05). 3) Compared to the control group, the serum malondialdehyde content of zinc protein group, zinc methionine group and zinc glycine group was significantly decreased (P<0.05). 4) There were no significant differences in serum total protein, albumin, triglyceride contents and alkaline phosphatase and aspartate transaminase activities among all groups (P>0.05). In conclusion, the different zinc sources have significant effects on laying rate, feed-to-egg ratio and serum estradiol and malondialdehyde contents of breeding geese during laying period; compared with zinc sulfate, dietaray zinc methionine and zinc glycine can improve the performance, serum reproductive hormone contents and antioxidant capacity of breeding geese during laying period.

This study aimed to investigate the effects of 25-hydroxyvitamin D₃ [25(OH)D₃] and coated 25(OH)D₃ on lactation performance, nutrient apparent digestibility, rumen fermentation parameters and serum indices of mid-lactation dairy cows. Fifty Holstein dairy cows with similar parity [(2.54±0.11) parities], days in milk [(116.3±15.6) d] and daily milk yield [(41.00±3.87) kg/d] were selected and randomly divided into 5 groups using a randomized complete block design, with 10 cows per group. The control group was fed a basal diet, while the experimental groups were respectively fed a basal diet+0.5 mg/d 25(OH)D₃ [in the form of uncoated 25(OH)D₃, L-D group], a basal diet+1.0 mg/d 25(OH)D₃ [in the form of uncoated 25(OH)D₃, H-D group], a basal diet+0.5 mg/d 25(OH)D₃ [in the form of coated 25(OH)D₃, L-CD group], and a basal diet+1.0 mg/d 25(OH)D₃ [in the form of coated 25(OH)D₃, H-CD group]. The experiment included a 10-day adaptation period followed by a 60-day formal trial period. The results showed as follows: 1) supplementation with 25(OH)D₃ or coated 25(OH)D₃ had no significant effect on dry matter intake (P>0.05). The milk yield, 4% fat-corrected milk (FCM) yield, lactose yield and feed efficiency in the L-D group, H-D group and L-CD group were significantly higher than those in the control group and H-CD group (P<0.05), and the 4% FCM yield in the L-CD group was significantly higher than that in the L-D group and H-D group (P<0.05). 2) The apparent digestibility of dry matter and neutral detergent fiber in the H-D group, L-CD group and H-CD group was significantly higher than that in the control group (P<0.05), and the apparent digestibility of organic matter in these three groups was significantly higher than that in the control group and L-D group (P<0.05). 3) Supplementation with 25(OH)D₃ or coated 25(OH)D₃ had no significant effect on ruminal pH (P>0.05), but significantly decreased the ruminal acetate/propionate (P<0.05); the total volatile fatty acid content in the H-D group was significantly higher than that in the other four groups (P<0.05). 4) The serum 25(OH)D₃ content in all experimental groups was significantly higher than that in the control group (P<0.05), with the highest value in the H-CD group, followed by the H-D group and L-CD group, and the lowest in the L-D group. The serum total antioxidant capacity in the L-D group, H-D group and L-CD group was significantly higher than that in the control group and H-CD group (P<0.05), while the serum malondialdehyde content in the H-D group and L-CD group was significantly lower than that in the control group, L-D group and H-CD group (P<0.05). In conclusion, supplementation with 1.0 mg/d uncoated 25(OH)D₃ or 0.5 mg/d coated 25(OH)D₃ can improve the lactation performance, feed efficiency, nutrient apparent digestibility and antioxidant status of mid-lactation dairy cows.

This experiment aimed to investigate the effects of supplementing with different dosages of Clostridium butyricum on the growth performance, body measurement indicators, serum biochemical indices, rumen fermentation parameters, and rumen microbial community structure in suckling calves. Forty healthy newborn Holstein female calves were selected and randomly divided into 4 groups with 10 calves in each group, and were housed in individual pens. The control group was fed routinely, while the calves in the 1 g group, 3 g group, and 5 g group were supplemented with 1, 3, and 5 g/(head·d) of Clostridium butyricum, respectively. The experimental period was 60 days. On trial day 21 (21 days of age), day 42 (42 days of age), and day 60 (60 days of age), before the morning feeding, the calves were weighed after fasting, their body measurement indicators were measured, and jugular vein blood was collected to determine serum biochemical indices. On day 60, rumen fluid was collected from the calves to determine rumen fermentation parameters and analyze the rumen microbial community structure. The results showed that: 1) compared with the control group, supplementing with 1 g/(head·d) of Clostridium butyricum significantly increased the body height of calves at 42 days of age (P<0.05). 2) At 42 days of age, the serum total protein and albumin contents in the 1 g group, and the serum globulin content in all Clostridium butyricum supplementation groups were significantly increased compared with the control group (P<0.05). 3) Compared with the control group, supplementing with 1 and 3 g/(head·d) of Clostridium butyricum significantly increased the ammonia nitrogen concentration in the rumen fluid of calves at 60 days of age (P<0.05). 4) Compared with the control group, the relative abundance of Lachnospiraceae_FE2018_group in rumen microbial community was significantly increased in the 1 g group (P<0.05); the relative abundances of Eubacterium_saphenum_group, Pasteurella and Roseburia in rumen microbial community were significantly increased in the 3 g group (P<0.05). In conclusion, supplementing with Clostridium butyricum has positive effects on the growth and development, rumen fermentation, serum biochemical indices, and rumen microbial community of suckling calves. Among them, a supplementation of 1 g/(head·d) shows better effects in promoting calf growth and development, while a supplementation of 3 g/(head·d) shows better effects in improving rumen fermentation function and microbial community structure.

This experiment investigated the effects of succinic acid, sodium butyrate and isobutyric acid on the growth performance, rumen fermentation parameters and rumen microbiota structure of suckling calves. Sixty-four healthy breeding male Holstein calves with similar body weight were selected and randomly assigned to four groups, they were control group (CK group), succinic acid group (SA group), sodium butyrate group (SB group), and isobutyric acid group (IB group), with 16 calves in each group. The experiment period lasted for 56 days. All groups received the same amount of milk, with the SA, SB, and IB groups supplemented with 1 g/L of succinic acid, sodium butyrate, and isobutyric acid in the milk, respectively. The results showed that: 1) from days 29 to 56, calves in the SA and SB groups exhibited significantly higher significantly increased average daily weight gain compared with the CK and IB groups (P<0.05). From days 1 to 56, the starter feed dry matter intake in the SB group was significantly higher than that in the other three groups (P<0.05). 2) At day 42, the concentration of rumen fluid ammonia nitrogen (NH₃-N) in the SA and SB groups was significantly higher than that in the CK group (P<0.05); the concentration of rumen fluid microbial protein (MCP) in the SA and SB groups was significantly higher than that in the CK group at days 28, 42 and 56 (P<0.05); the concentration of rumen fluid acetic acid in the SB group was significantly higher than that in the CK group at both days 28 and 56 (P<0.05), while the concentration of rumen fluid propionic acid in the SB group was significantly higher than that in all other groups at day 42 (P<0.05); the concentrations of butyric acid and total volatile fatty acid in the CK group at day 56 were significantly lower than those in the other three groups (P<0.05). 3) For rumen microbiota, at day 28, the SA group exhibited a significantly higher relative abundances of Thermodesulfobacteriota and Spirochaetota compared with the CK group (P<0.05); at day 56, the relative abundance of Methanobacteriota in the SA group was significantly lower than that in the CK and IB groups (P<0.05). LEfSe analysis indicated that, at day 28, Desulfovibrio and Fibrobacter were significantly enriched in the SA group, and the Rikenellaceae_RC9_gut_group and Prevotellaceae_NK3B3l_group were significantly enriched in IB group; at day 56, the Fibrobacter was significantly enriched in the SA group, the Desulfovibrio was significantly enriched in the SB group, and the Syntrophococcus and Ruminococcus_gauvreauii_group were significantly enriched in the IB group. In conclusion, supplementation with succinic acid and sodium butyrate in milk can improve the growth performance of suckling calves. Furthermore, the supplementation with succinic acid, sodium butyrate, and isobutyric acid in milk can promote the ruminal development and change the rumen microbiota structure of suckling calves. Among them, sodium butyrate has the best feeding effect, followed by succinic acid and isobutyric acid.

The aim of this experiment was to investigate the effects of Codonopsis pilosula polysaccharides (CPP) on growth performance, nutrient digestion, rumen fermentation and microbiota in yak calves. A one-way randomized experimental design was used to select 27 yak male calves around 6 months of age, with an average weight of (72.61±1.35) kg and in good health condition, and randomly divided into three groups: control group (CN group, fed only the basal diet), low-dose group (DSL group, with 5 g/d of CPP added to the basal diet), and high-dose group (DSH group, with 10 g/d of CPP added to the basal diet). Nine replicates of 1 cow per group were housed in a single pen. The pre-test period was 10 d, and the positive test period was 60 d. Results showed as follows: 1) the average daily gain (ADG) of the DSH group was extremely significantly higher than that of the CN group (P<0.01), the final body weight (FBW) and average daily feed intake (ADFI) were significantly higher than that of the CN group (P<0.05), and the ADFI was significantly higher than that of the DSL group (P<0.05). 2) The neutral detergent fiber (NDF) digestibility of the DSH group was significantly higher than that of the CN group and DSL group (P<0.05). 3) The total volatile fatty acid (TVFA) concentration of the DSH group was extremely significantly higher than that of the CN group and DSL group (P<0.01), and the acetic acid (AA) concentration was significantly higher than that of the CN group and DSL group (P<0.05) 4) The Shannon index, ACE index, and Chao1 index of the DSH group were extremely significantly higher than those of the CN group (P<0.01), the ACE index and Chao1 index of the DSL group were extremely significantly higher than those of the CN group (P<0.01), and the ACE index of the DSH group was extremely significantly higher than that of the DSL group (P<0.01); at the rumen microbial genus level, the relative abundance of Ruminococcus in the DSH group was extremely significantly higher than that of the CN group (P<0.01), and the relative abundance of Candidatus_Saccharimonas was significantly higher than that of the CN group (P<0.05); functional prediction analysis results showed that the lipid metabolism, folding, sorting and degradation pathways were extremely significantly enriched in the DSH group (P<0.01), and the coenzyme and vitamin metabolism, terpenoid and polyketide metabolism pathways were significantly enriched in the DSH group (P<0.05). 5) Correlation analysis showed that ADG, ADFI, concentrations of TVFA and AA were significantly positively correlated with the relative abundance of Ruminococcus and the coenzyme and vitamin metabolism pathway (P<0.05); ADFI, concentrations of TVFA and AA were significantly positively correlated with the folding, sorting and degradation pathway (P<0.05); F/G was significantly positively correlated with other amino acid metabolism pathway (P<0.05). The above results indicate that the addition of CPP to the diet can improve growth performance, NDF digestibility, TVFA and AA concentrations, and rumen microflora in yak calves.

The aim of this experiment was to study the effects of bile acids on growth performance, nutrient digestion, rumen fermentation and microbiota of yak calves. Twenty-seven weaned male yaks of about 6 months of age with similar body weight [(70.93±2.86) kg] were selected and randomly divided into three groups of nine yaks each. The control group (CN group) was fed a basal diet, and the experimental groups was fed the basal diet supplemented with either 6 (DL group) or 12 g/(d·head) (DH group) of bile acids. The pre-feeding period lasted for 10 days, and the main trial period lasted for 60 days. The results showed as follows: 1) the final weight, average daily gain (ADG), average dry matter intake (ADMI), neutral detergent fiber digestibility, total volatile fatty acids, and acetic acid concentrations in the DH group were significantly higher than those in the CN group (P<0.05). 2) The Shannon index, ACE index and Chao1 index of rumen fluid microbiota were significantly higher in DH and DL groups than those in CN group. (P<0.05); in terms of relative abundance of rumen microbial communities, the relative abundance of unclassified_k_norank_d_Bacteria, Synergistetes, and Ruminococcus in the DH group were significantly higher than those in the CN and DL groups (P<0.05). Functional prediction analysis results showed that pathways including lipid metabolism, carbohydrate metabolism, energy metabolism, and lipid transport and metabolism were significantly enriched in the DH group (P<0.05). 3) Correlation analysis found that ADG and ADFI were significantly positively correlated with lipid metabolism pathway (P<0.05), and AA concentration was significantly positively correlated with the relative abundance of Ruminococcus (P<0.05). The above results indicate that dietary supplementation of bile acids can enhance nutrient digestion and utilization, improve rumen microbial structure, and promote growth and development in yak calves. Under the conditions of this experiment, the effect of the DH group is the best.

This experiment was conducted to investigate the energy requirement of Yunshang black goats during lactation. Fifty healthy Yunshang black goats in early lactation with good body condition, body weight of (61.03±1.92) kg and second parity were randomly assigned to 5 groups with 10 replicates per group and 1 goat per replicate. The dietary metabolic energy (ME) levels in 5 groups (groups 1 to 5) were: pre-lactation (days 1 to 30), 7.55, 8.00, 8.45, 8.90 and 9.35 MJ/kg; mid-lactation (days 31 to 60), 7.49, 7.98, 8.49, 8.98 and 9.46 MJ/kg; late-lactation (days 61 to 90), 7.70, 8.20, 8.70, 9.20 and 9.70 MJ/kg. The pre-experimental period lasted for 10 days, and the experimental period lasted for 90 days. The digestive and metabolic experiments were carried out on days 16 to 20, days 46 to 50 and days 66 to 70 of lactation, respectively. The results showed as follows: 1) with the dietary energy level increased, the average daily gain (ADG) during pre-lactation, mid-lactation, late-lactation and whole lactation was significantly linearly increased (P<0.05), and the final body weights (FBW) during mid-lactation and late-lactation was significantly linearly increased (P<0.05). 2) With the dietary energy level increased, the milk yield (MY) and fat and protein corrected milk yield (FPCM) during pre-lactation, mid-lactation, late-lactation and whole lactation were significantly linearly increased (P<0.05), and the contents of total solids, milk protein and lactose in milk during pre-lactation, mid-lactation and late-lactation were significantly linearly increased (P<0.05). 3) With the dietary energy level increased, the gross energy of ingestion, methane energy, apparent digestible energy, apparent metabolizable energy, milk energy, gross energy digestibility and gross energy metabolic rate during pre-lactation and late-lactation were significantly linearly increased (P<0.05). 4) The regression formulas of maintenance metabolic energy (ME_m) requirement during pre-lactation, mid-lactation and late-lactation were as follows: ME_m = 0.511W^0.75 + 0.037ADG + 1.805MY(R² = 0.930), ME_m = 0.439W^0.75 + 0.053ADG + 0.746MY(R² = 0.918), ME_m = 0.400W^0.75 + 0.030ADG + 3.451MY(R² = 0.958). In conclusion, increasing dietary energy level can improve the growth performance and milk quality of Yunshang black goats during lactation, and increase the energy metabolism efficiency; the ME_m requirement during pre-lactation, mid-lactation and late-lactation are 0.51, 0.44 and 0.40 MJ/kg W^0.75, respectively, and the metabolic energy required per kilogram of milk production are 1.81, 1.86 and 3.45 MJ, respectively.

This experiment aimed to explore the effects of two different dietary protein sources, namely soybean meal and corn gluten meal, on growth performance and gastrointestinal antioxidant and immune functions of goats. Twenty-four Xiangdong black goats with good physical condition and similar body weight of (12.45±1.80) kg were selected and randomly divided into the corn gluten meal group (CGM group) and the soybean meal group (SBM group), with corn gluten meal and soybean meal as the dietary protein sources, respectively. There were 12 replicates in each group, and one goat in each duplicate. The pre-test period was 10 days and the formal test period was 60 days. The results showed as follows: 1) compared with CGM group, the average daily gain, dry matter intake, carcass weight and dressing percentage of goats in SBM group were significantly increased (P<0.05), and the feed to gain ratio was significantly decreased (P<0.05). 2) Compared with CGM group, the catalase activity in rumen mucosa in SBM group was significantly increased (P<0.05). 3) Compared with CGM group, the contents of interleukin-1β (IL-1β) and tumor necrosis factor-α in rumen mucosa in SBM group were significantly decreased (P<0.05), and the contents of IL-1β and interleukin-10 (IL-10) in colonic mucosa were significantly increased (P<0.05). 4) β diversity analysis showed that there were significant clustering differences in microbiota both in rumen and colonic mucosa between the two groups (P<0.05). Compared with CGM group, the Desulfobacterota_I relative abundance in rumen mucosa in SBM group was significantly decreased (P<0.05), and the Prevotella relative abundance in colonic mucosa was significantly increased (P<0.05). 5) The correlation analysis indicated that, in rumen mucosa, the Desulfovibrio_R_446353 relative abundance was significantly negatively correlated with the glutathione peroxidase activity [correlation coefficient (r)<-0.5, P<0.05], the Prevotella relative abundance was significantly negatively correlated with the interleukin-2 content (r<-0.5, P<0.05), and the Butyrivibrio_A_168226 relative abundance was significantly positively correlated with the IL-10 content (r>0.5, P<0.05); in colonic mucosa, the Akkermansia relative abundance was significantly negatively correlated with the contents of IL-1β and IL-10 (r<-0.5, P<0.05), and the Butyrivibrio_A_168226 relative abundance was significantly positively correlated with the IL-10 content (r>0.5, P<0.05). In conclusion, compared with corn gluten meal, soybean meal as a dietary protein source can significantly improve the growth performance and slaughter performance of goats, and at the same time enhance the immune function by improving the microbiota composition in gastrointestinal mucosa.

This experiment aimed to investigate the effects of dietary supplementation with rumen-protected puerarin (RPPUE) and rumen-protected guanidinoacetic acid (RPGAA) on nutrient apparent digestibility, rumen fermentation parameters and microbiota composition of goats. A 2×2 two-factor experimental design was adopted, and sixty healthy 7-month-old Chuanzhong black goats with similar body weight were randomly divided into 4 groups with 3 replicates per group and 5 goats per replicate. The control group (CON group) was fed a basal diet, while the experimental groups were supplemented with 0.1% RPPUE (RPPUE group), 0.1% RPGAA (RPGAA group) and a mixture of 0.1% RPPUE+0.1% RPGAA (RPPUE+RPGAA group) in the concentrate of the basal diet, respectively. The experimental period lasted for 70 days, including a 10-day adaptation period and a 60-day formal experimental period. The results showed that compared with the CON group, dietary supplementation with RPPUE extremely significantly increased the apparent digestibility of neutral detergent fiber and acid detergent fiber, and the total volatile fatty acid content in rumen (P<0.01), extremely significantly increased the relative abundance of Veillonellaceae_UCG-001 (P<0.01), extremely significantly decreased the ammonia nitrogen content and the relative abundance of Lachnospiraceae_UCG-002 in rumen (P<0.01), significantly increased the apparent digestibility of organic matter and crude protein, and the butyric acid content in rumen (P<0.05), and significantly increased the relative abundances of Verrucomicrobiota, Bacteroidota, and Prevotella in rumen (P<0.05); dietary supplementation with RPGAA extremely significantly increased the apparent digestibility of organic matter and acid detergent fiber, and the total volatile fatty acid content in rumen (P<0.01), significantly increased the apparent digestibility of crude protein and the contents of isobutyric acid, butyric acid and valeric acid in rumen(P<0.05), significantly increased the relative abundances of Spirochaetota, Succiniclasticum, and Prevotella (P<0.05), and significantly decreased the relative abundance of Bacteroidota (P<0.05). There was an extremely significant interaction effect between RPPUE and RPGAA on the total volatile fatty acid content in rumen (P<0.01). In conclusion, dietary supplementation with RPPUE and RPGAA can improve nutrient apparent digestibility, enhance rumen fermentation function and optimize the microflora structure in goats.

This experiment aimed to explore the effects of dietary supplementation with different doses of bile acids on rumen microbiota and fermentation characteristics of goats. Fifteen 10-month-old healthy Chuanzhong black goats with an initial body weight of (31.18±0.14) kg were selected and randomly divided into 3 groups, with 5 replicates in each group and 1 goat in each replicate. The control group (CON group) was fed with a basal diet, while the low-dose bile acid group (LBA group) was fed with the basal diet+1.5 g/kg DM bile acid, and the high-dose bile acid group (HBA group) was fed with the basal diet+4.5 g/kg DM bile acid. The experiment lasted for 60 days after a 7-day adaptation. The results showed as follows: 1) compared with CON group, the final body weight in HBA group was significantly increased (P<0.05). 2) Compared with CON group, the rumen acetate concentration in HBA group was significantly increased (P<0.05), while the rumen propionate concentration in LBA group and HBA group was significantly decreased (P<0.05). 3) Compared with CON group, the Chao1 and Shannon indices of rumen microbiota in HBA group were significantly increased (P<0.05); permutational multivariate analysis of variance (PERMANOVA) indicated that there were significant differences in rumen microbiota structure among the groups (P<0.05). 4) Compared with CON group, at the phylum level, the rumen Bacillota relative abundance in LBA group and HBA group was significantly increased (P<0.05), and the rumen Fibrobacterota relative abundance in HBA group was significantly increased (P<0.05); at the genus level, the rumen Prevotella relative abundance in LBA group and HBA group was significantly decreased (P<0.05), while the rumen Fibrobacter relative abundance in HBA group was significantly increased (P<0.05). 5) The function annotation of Kyoto Encyclopedia of Genes and Genomes Orthology (KO) showed that compared with CON group, the relative abundance of biosynthesis of other secondary metabolites pathway in LBA group and HBA group was significantly increased (P<0.05); meanwhile, the K01179 (endoglucanase) relative abundance in HBA group was significantly increased (P<0.05), while the K00625 (phosphate acetyltransferase) relative abundance in LBA group and HBA group was significantly decreased (P<0.05). In conclusion, bile acids can enhance fiber degradation capacity, increase acetate production, and alter rumen fermentation patterns by regulating the structure and metabolic function of rumen microbiota. Moreover, high-dose bile acids (4.5 g/kg DM) have a more significant effect.

This experiment was conducted to investigate the effects of dietary cottonseed protein concentrate on growth performance, muscle texture characteristics, serum biochemical indices, enzyme activities and intestinal and liver morphology of Ictalurus punctatus. A total of 360 healthy Ictalurus punctatus with an initial body weight of (135.32±3.87) g were randomly divided into 6 groups with 3 replicates per group and 20 fish per replicate. Each group was fed isonitrogenous and isolipidic experimental diets supplemented with 0% (group D1), 6% (group D2), 12% (group D3), 18% (group D4), 24% (group D5) and 30% (group D6) cottonseed protein concentrate, respectively, for a 90-day feeding trial. The results showed as follows: 1) the weight gain rate (WGR) of groups D2 and D3 was significantly higher than that of groups D5 and D6 (P<0.05); the feed conversion ratio (FCR) and feeding rate (FR) of groups D1 to D4 were significantly lower than those of groups D5 and D6 (P<0.05); the protein efficiency ratio (PER) of groups D2 and D4 was significantly higher than that of groups D1, D5 and D6 (P<0.05); the condition factor (CF) of groups D1 to D5 was significantly lower than that of group D6 (P<0.05). 2) The muscle springiness of group D1 was significantly lower than that of groups D2 to D6 (P<0.05); the muscle chewiness and gumminess were significantly lower than those of group D2 (P<0.05); the muscle resilience was significantly higher than that of groups D2 and D3 (P<0.05). 3) The serum total bilirubin (T-Bil-V) content of groups D1 and D2 was significantly higher than that of groups D4 to D6 (P<0.05); the serum albumin (ALB) content of group D4 was significantly higher than that of group D1 (P<0.05); the serum lactate dehydrogenase (LDH) activity of groups D4 to D6 was significantly lower than that of group D1 (P<0.05). 4) Group D2 had the highest activities of foregut lipase, α-amylase (α-AMY) and stomach lipase; group D4 had the highest activities of liver lipase and protease, stomach α-AMY and foregut protease, with the activities of stomach α-AMY and foregut protease significantly higher than those of other groups (P<0.05); group D3 had the highest activities of liver α-AMY and stomach protease, with the liver α-AMY activity significantly higher than that of other groups (P<0.05). 5) Mild congestion and dilation of small-area hepatic sinusoids were observed in the liver tissues of groups D4 to D6, and hepatocyte necrosis and inflammatory cell infiltration occurred in group D6. In conclusion, the appropriate dietary supplementation level of cottonseed protein concentrate for Ictalurus punctatus is 6% to 12%, and the maximum level should not exceed 18%.

This experiment was conducted to study the effects of dietary different levels of compound micro-minerals (IMM) premix on growth performance, serum biochemical indices and minerals accumulation of juvenile American eel (Anguilla rostrata), and preliminarily determined the appropriate supplemental level of compound IMM premix in the diet. A total of 500 juvenile American eels with an average body weight of (22.99±0.15) g were randomly divided into 5 groups with 4 replicates per group and 25 fish per replicate. Fish in 5 groups were fed experimental diets which the compound IMM premix supplemental levels were 0 (IMM0 group), 600 (IMM600 group), 1 200 (IMM1200 group), 1 800 (IMM1800 group) and 2 400 mg/kg (IMM2400 group), respectively. The experiment lasted for 70 days. The results showed as follows: 1) the final body weight (FBW), weight gain rate (WGR), specific growth rate (SGR) and feed intake (FI) of IMM600 group and IMM1200 group were significantly higher than those of other groups (P<0.05). When the dietary compound IMM premix supplemental level was 1 040 mg/kg, the experimental fish obtained the best WGR. 2) The contents of triglycerides (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and the activities of glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) in serum of IMM1200 group were significantly lower than those of IMM0 group (P<0.05), and the contents of high-density lipoprotein cholesterol (HDL-C), immunoglobulin M (IgM), complement 3 (C3) and the activities of lysozyme (LZM), acid phosphatase (ACP), alkaline phosphatase (AKP) in serum were significantly higher than those of IMM0 group (P<0.05). 3) Compared with IMM0 group, the contents of calcium, phosphorus, iron, manganese and zinc in whole fish of IMM1200 group were significantly increased (P<0.05), the accumulation rates of calcium, phosphorus and iron in whole fish were significantly increased (P<0.05), and the contents of calcium, phosphorus, iron, manganese and zinc in vertebrae were significantly increased (P<0.05). In conclusion, under the conditions of this experiment, the appropriate supplemental level of compound IMM premix in the diet is 1 040 to 1 200 mg/kg.

To investigate the dietary vitamin D₃ requirement of red swamp crayfish (Procambarus clarkii), a feeding trial was conducted using 270 crayfish with an initial body weight of (4.33±0.01) g. Six vitamin D₃ supplementation levels were set in the basal diet: 0 (control group, measured value 2 700 IU/kg, designated as D1 group), 3 000 (measured value 6 160 IU/kg, designated as D2 group), 6 000 (measured value 9 200 IU/kg, designated as D₃ group), 12 000 (measured value 15 300 IU/kg, designated as D4 group), 24 000 (measured value 29 700 IU/kg, designated as D5 group), and 48 000 IU/kg (measured value 55,100 IU/kg, designated as D6 group). Each group had 3 replicates with 15 crayfish per replicate, and the trial lasted for 8 weeks. Results showed as follows: the weight gain rate (WGR), specific growth rate (SGR), and feed conversion ratio (FCR) in the D5 group showed the optimal values, with significant differences compared with the D1 group (P<0.05); compared with the D1 group, the activities of hepatopancreatic protease, lipase, and amylase in the D5 group were significantly increased (P<0.05), and the hepatopancreatic B cell frequency, intestinal villus length and width were significantly increased (P<0.05); the calcium and phosphorus contents in the hepatopancreas and carapace increased with the elevation of dietary vitamin D₃ supplementation level, with the D5 group achieving the maximum values that were significantly higher than those in the D1 group (P<0.05). Compared with the D1 group, the relative mRNA expression levels of hepatopancreatic molting-related genes [chitinase (CHI), ecdysone receptor (ECR), retinoic acid X receptor (RXR)] and immune-related genes [Toll-like receptor 2 (TLR2), anti-lipopolysaccharide factor 2 (ALF2), lysozyme (LZM), myeloid differentiation factor 88 (MyD88)] in the D5 group were all significantly upregulated (P<0.05), while the relative mRNA expression level of molt-inhibiting hormone (MIH) was significantly downregulated (P<0.05). In conclusion, dietary vitamin D₃ supplementation can improve the growth performance, intestinal development, digestive capacity, and non-specific immunity of Procambarus clarkii. Based on quadratic regression analysis, the suitable dietary vitamin D₃ requirement for Procambarus clarkii is determined to be 33 117 to 35 032 IU/kg.

This study aimed to investigate the effects of phocaecholic acid and porcine bile acid on growth performance, serum biochemical indices, antioxidant capacity and intestinal digestive enzyme activities of Litopenaeus vannamei. A total of 600 healthy Litopenaeus vannamei with good growth performance, uniform size and an initial body weight of (2.50±0.15) g were randomly divided into 5 groups, with 3 replicates per group and 40 shrimp per replicate. The control group was fed a basal diet, while the experimental groups were fed the basal diets supplemented with 500 or 1 000 mg/kg phocaecholic acid (HD500 group, HD1000 group) or porcine bile acid (ZD500 group, ZD1000 group). The experimental period lasted for 56 days. The results showed as follows: 1) compared with the control group, there were no significant changes in weight gain rate, specific growth rate or feed intake in the HD500 group, HD1000 group, ZD500 group and ZD1000 group (P>0.05), with the HD500 group exhibiting the best growth performance. 2) Compared with the control group, the serum total cholesterol (TC), triglyceride (TG) and low-density lipoprotein cholesterol (LDL-C) contents in the HD1000 group, ZD500 group and ZD1000 group were significantly decreased (P<0.05). The serum TG and LDL-C contents, as well as the activities of acid phosphatase (ACP) and alkaline phosphatase (AKP) in the HD500 group, were significantly higher than those in the ZD500 group (P<0.05). 3) Compared with the control group, the hepatopancreas total antioxidant capacity (T-AOC) in the HD500 group, HD1000 group, ZD500 group and ZD1000 group was significantly increased (P<0.05). The hepatopancreas reduced glutathione (GSH) content in the HD500 group was significantly higher than that in the other 4 groups (P<0.05), and the hepatopancreas malondialdehyde (MDA) content was significantly lower than that in the control group, HD1000 group and ZD1000 group (P<0.05). 4) Compared with the control group, the intestinal trypsin activity in the HD1000 group, ZD500 group and ZD1000 group was significantly decreased (P<0.05), the intestinal amylase activity in the HD500 group and ZD1000 group was significantly increased (P<0.05), and the intestinal lipase activity in the HD500 group, ZD500 group and ZD1000 group was significantly increased (P<0.05). The intestinal amylase activity in the HD500 group was significantly higher than that in the HD1000 group and ZD500 group (P<0.05), and the intestinal lipase activity was significantly higher than that in the HD1000 group (P<0.05). In conclusion, dietary supplementation of appropriate amounts of phocaecholic acid and porcine bile acid has positive effects on the serum biochemical indices, antioxidant capacity and intestinal digestive enzyme activities of Litopenaeus vannamei, and phocaecholic acid is superior to porcine bile acid in improving antioxidant capacity and intestinal digestive enzyme activities. Under the experimental conditions, supplementing 500 mg/kg phocaecholic acid in the diet of Litopenaeus vannamei yields the best effect.

This study aimed to investigate the effects of dietary quercetagetin (QG) on the reproductive performance and gut microbiota of female rabbits and growth performance of their offspring under heat stress condition, and to determine its optimal supplementation level. A total of 460 female Ira rabbits with the similar parity (from 2 to 3 parities) and body weight (from 3.5 to 4.5 kg) were randomly divided into 5 groups with 92 rabbits per group, and the rabbits were individually raised in cages. The control group was fed a basal diet, while the QG100, QG200, QG400 and QG600 groups were fed the basal diet supplemented with 100, 200, 400 and 600 mg/kg QG, respectively. The experiment lasted for 71 days, including a 6-day adaptation period and a 65-day formal trial (from mating to weaning of kits). The results showed that: 1) compared with the control group, the conception rate of female rabbits in the QG600 group was significantly increased (P<0.05), and the litter size and litter size born alive of female rabbits in the QG600 group were significantly increased (P<0.05); furthermore, the total litter size, total litter size born alive, total litter birth weight, litter weight born alive, and litter weight born alive at birth of female rabbits in the QG600 group were also significantly increased (P<0.05); the number of kits per litter and litter weight at 7, 14, 21 and 35 days of age were significantly higher in the QG400 and QG600 groups (P<0.05). 2) On day 15 of gestation, compared with the control group, the serum contents of progesterone (P) and interleukin-10 (IL-10), the activities of glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD), and total antioxidant capacity (T-AOC) in the QG600 group were significantly increased (P<0.05), while malondialdehyde (MDA) content was significantly decreased (P<0.05). 3) Compared with the control group, dietary supplementation with 600 mg/kg QG showed a tendency to improve the gut microbiota diversity of female rabbits under heat-stress conditions. At the phylum level, dietary supplementation with 600 mg/kg QG increased the relative abundances of Bacteroidota (35.06% vs. 31.70%) and Verrucomicrobiota (2.61% vs. 1.78%). At the genus level, it increased the relative abundances of unclassified_f_Lachnospiraceae (9.78% vs. 9.23%) and unclassified_o_Clostridia_vadinBB60_group (9.32% vs. 7.90%). In conclusion, dietary supplementation with 600 mg/kg QG can improve the reproductive performance of female rabbits and the growth performance of their offspring under heat stress condition, and it also can exert a modulatory effect on the gut microbiota of female rabbits.

This experiment aimed to investigate the effects of replacing different proportions of lawn grass in the diet with licorice residue (LR) on the growth performance, intestinal morphology, digestive enzyme activities, and immune function of meat rabbits. A total of 120 healthy 35-day-old commercial Ira weaned rabbits with similar body weight were randomly assigned to one control group and four test groups, with 4 replicates per group and 6 rabbits per replicate. The control group (0%LR group) was fed a basal diet containing 20% lawn grass. The four test groups were fed experimental diets in which LR replaced 15% (15%LR group), 30% (30%LR group), 45% (45%LR group), and 60% (60%LR group) of the lawn grass in the basal diet, respectively. The experiment included a 7-day adaptation period followed by a 49-day formal trial period. The results showed that: 1) no significant differences were observed in the diarrhea rate and mortality among all groups (P>0.05). The average daily feed intake (ADFI) of the 15%LR and 30%LR groups was significantly higher than that of the 0%LR and 60%LR groups (P<0.05). The final body weight (FBW) of the 15%LR group was significantly higher than that of all other groups (P<0.05), and its average daily gain (ADG) was significantly higher than that of the 0%LR, 45%LR and 60%LR groups (P<0.05). 2) The duodenal muscularis thickness and ileal crypt depth of the 15%LR group were significantly greater than those of all other groups (P<0.05). The jejunal muscularis thickness in the 15%LR group was significantly greater than that in the 0%LR, 45%LR and 60%LR groups (P<0.05). 3) The activities of lipase and α-amylase in the duodenum of the 15%LR group were significantly higher than those in the 0%LR, 45%LR and 60%LR groups (P<0.05). The activities of trypsin in the jejunum and α-amylase in the ileum of the 15%LR group were significantly higher than those of all other groups (P<0.05). The lipase activity in the jejunum of the 15%LR group was significantly higher than that of the 0%LR, 30%LR and 60%LR groups (P<0.05). The cellulase activity in the cecum showed a significant linear increase with the increasing of LR replacement ratio (P<0.05). 4) No significant difference was found in the pH of gastric contents among the groups (P>0.05). The pH of the duodenal, jejunal, and ileal contents exhibited significant linear changes in response to the increasing of LR replacement ratio (P<0.05). 5) Liver weight showed a significant quadratic curve change with the increasing of LR replacement ratio (P<0.05). The liver weight of the 15%LR group was significantly higher than that of the 30%LR group (P<0.05), and the liver index of the 15%LR group was significantly higher than that of the 0%LR group (P<0.05). 6) No significant differences were observed in serum immunoglobulin M (IgM) content among the four test groups (P>0.05), but all of them were significantly higher than that of the 0%LR group (P<0.05). In conclusion, replacing an appropriate amount of lawn grass with LR in the diet can improve the growth performance, intestinal morphology, certain digestive enzyme activities, and immune function of meat rabbits, and a replacement ratio of 15% is considered appropriate.

This experiment aimed to study the long non-coding RNA (lncRNA) and mRNA profiles in jejunal tissues of piglets before and after weaning, explore the regulatory roles of lncRNA in intestine of weaned piglets, identify lncRNA closely associated with intestinal injury or repair, and provide a theoretical foundation for nutritional strategies to improve intestinal health in weaned piglets. A total of 18 piglets with similar genetic background and body weight of (4.01±0.05) kg were selected and randomly divided into 3 groups at post-weaning day 0 (the day of weaning, D0 group), day 3 (D3 group), and day 7 (D7 group), with 6 piglets in each group (2 females and 4 males), respectively. Among them, the piglets in D3 and D7 groups were weaned at 21 days of age, while those in D0 group continued to nurse. The piglets in each group were slaughtered on day 0, day 3 and day 7 after weaning, respectively. The results showed as follows: 1) compared with D0 group, the serum D-lactic acid (D-LA) content and diamine oxidase activity in D3 group were significantly increased (P<0.05), while the activities of serum superoxide dismutase (SOD), catalase and glutathione peroxidase were significantly decreased (P<0.05); the serum D-LA content in D7 group was significantly increased (P<0.05), and the serum SOD activity was significantly decreased (P<0.05). 2) Compared with D0 group, the jejunal villus height (VH) and villus height to crypt depth ratio (V/C) in D3 and D7 groups were significantly decreased (P<0.05), and the jejunal crypt depth (CD) was significantly increased (P<0.05). Compared with D3 group, the jejunal VH and V/C in D7 group were significantly increased (P<0.05), and the jejunal CD was significantly decreased (P<0.05). 3) Transcriptome sequencing of jejunal tissues revealed that a total of 3 322 lncRNA were expressed in jejunum of weaned piglets, among which 1 772 were annotated and 1 550 were novel. Concurrently, 25 491 mRNA were identified. 4) Compared with D0 group, the number of differentially expressed lncRNA in D3 and D7 groups was 727 and 724, and the number of differentially expressed mRNA was 5 035 and 4 571, respectively. Compared with D3 group, the numbers of differentially expressed lncRNA and mRNA in D7 group were 227 and 2 438, respectively. 5) Functional enrichment analysis revealed that, compared with D0 group, the target genes of differentially expressed lncRNA in D3 and D7 groups were predominantly enriched in pathways including inflammatory bowel disease, antigen processing and presentation, cell adhesion molecules, and nuclear factor-kappa B signaling pathway. 6) A total of 5 differentially expressed lncRNA and mRNA were selected, and real-time quantitative PCR verified that the results were consistent with the trend of high-throughput sequencing. 7) Six pairs of lncRNA-target gene transcripts showing differential expression in both components were selected as likely regulators of intestinal function in weaned piglets. Target genes of these lncRNA included claudin 10 (CLDN10), DnaJ heat shock protein family member C2 (DNAJC2), C-X-C motif chemokine ligand 8 (CXCL8), hepatocyte growth factor (HGF), Toll-like receptor 9 (TLR9), and nitric oxide synthase 2 (NOS2), which were involved in intestinal permeability, oxidative stress, inflammatory response, and repair of intestinal cellular damage. In summary, weaning leads to oxidative stress, increases intestinal permeability, disrupts mucosal barrier and causes abnormal expression of intestinal lncRNA and mRNA in piglets. Differentially expressed lncRNA and target genes are involved in the process of intestinal injury and reconstruction. This study provides a reference for further revealing the regulatory roles of lncRNA and related mechanisms in intestine of weaned piglets.

This study investigated the protective effects and underlying mechanisms of Allium polyrhizum Turcz. ex Regel flavonoids (APTF) against deoxynivalenol (DON)-induced proventriculitis in chicken embryos. Healthy Hy-Line brown fertilized eggs at 0 day of embryo age were randomly allocated into four groups as control group (CON group), DON group (10 μg DON per egg), APTF group (150 μg APTF per egg), and DON+APTF group (10 μg DON+150 μg APTF per egg). The model was established via allantoic cavity injection at 9 days of embryo age, with evaluations including glandular stomach histopathology, DON residues, inflammatory factor levels, and pyroptosis-related protein expression at 15 days of embryo age. Key findings demonstrated: 1) DON exposure significantly reduced the organ index of glandular stomach (P<0.05), inducing mucosal epithelial shedding, glandular atrophy, and inflammatory cell infiltration, while APTF intervention markedly alleviated these pathological damages. 2) High performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) analysis indicated that APTF did not significantly affect DON residues in glandular stomach (P>0.05), suggesting that its mechanism targets were downstream toxicity pathways. 3) qPCR and Western blot analyses revealed that DON significantly upregulated the mRNA relative expression levels of interleukin-1β (IL-1β), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), cyclic GMP-AMP synthase (cGAS), and stimulator of interferon genes (STING) and protein relative expression levels of Toll-like receptor 4 (TLR4), NOD-like receptor thermal protein domain associated protein 3 (NLRP3), cleaved Caspase-3, and gasdermin E (GSDME) (P<0.05), whereas APTF intervention significantly suppressed these molecular changes (P<0.05). Thus, it can be concluded that APTF alleviates DON-induced proventriculitis by inhibiting TLR4/nuclear factor-κB(NF-κB)/NLRP3 inflammatory signaling pathway and Caspase-3/GSDME-dependent pyroptosis pathway, providing a theoretical basis for developing targeted pyroptosis inhibitors as detoxifying agents against mycotoxins.

In this study, we employed the porcine ear margin fibroblasts (PEMFs) as a model system to evaluate the protective effects of cycloastragenol (CAG) against cryoinjury and to elucidate the underlying molecular mechanisms. The cell counting kit-8 (CCK-8) assay was used to determine the effects of CAG on proliferation of thawed PEMFs at passages 3 (P3), 6 (P6), and 9 (P9). The median effect concentration (EC₅₀) of CAG was calculated using nonlinear regression (Hill model) in GraphPad Prism 9.5. Intracellular mitochondrial membrane potential and levels of reactive oxygen species (ROS) and mitochondrial superoxide were quantified via flow cytometry. Western blotting, immunofluorescence, and transmission electron microscopy were integrated to analyze alterations in the phosphatase and tensin homolog-induced putative kinase 1 (PINK1)-Parkin mitophagy pathway and the expression of autophagy markers light chain 3B (LC3B) and p62. To validate the involvement of the p62-Kelch-like ECH-associated protein 1 (Keap1)-nuclear factor E2-related factor 2 (Nrf2)-NAD(P)H quinone dehydrogenase 1 (NQO1) signaling axis, PEMFs were treated with the p62 inhibitor PTX80 and the Nrf2 inhibitor ML385, followed by re-evaluation of ROS and mitochondrial superoxide levels. Finally, transcriptome sequencing (RNA-Seq) was conducted to elucidate the gene networks and pathways modulated by CAG. The results showed that CAG treatment extremely significantly enhanced the mitochondrial membrane potential in PEMFs (P<0.01), while extremely significantly reduced the intracellular levels of ROS and mitochondrial superoxide as well as DNA damage (P<0.01). Although CAG treatment led to suppression of the PINK1-Parkin-mediated mitophagy pathway, it concurrently significantly upregulated the protein expression levels of autophagy markers p62 and LC3B (P<0.05). Transmission electron microscopy revealed a reduction in autophagosome numbers, while intracellular accumulation of p62 promoted nuclear translocation of Nrf2 and elevated protein expression of downstream target NQO1 (P<0.05). Upon specific inhibition of p62 or Nrf2, both ROS and mitochondrial superoxide levels in PEMFs were significantly increased (P<0.05), underscoring the critical role of the p62-Keap1-Nrf2-NQO1 axis in CAG-mediated antioxidative protection. Transcriptomic analysis revealed that differentially expressed genes were predominantly enriched in pathways related to antioxidative response, redox enzyme activity, autophagy regulation, cellular senescence, respiratory chain, mitochondrial structure, and DNA repair mechanisms. Heatmap visualization further demonstrated significant upregulation of canonical antioxidant genes, including superoxide dismutases, heat shock proteins, and peroxiredoxins, consistent with both protein-level and functional assay findings. In conclusion, the present study demonstrates that CAG activates the p62-Keap1-Nrf2-NQO1 signaling axis to maintain mitochondrial homeostasis and strengthen both antioxidant defenses and DNA repair capacity, thereby providing a robust theoretical foundation for optimizing cryopreservation protocols of porcine somatic cells.

This study aimed to investigate the effects of selenium yeast (SeY) on diquat-induced autophagy in chicken small intestinal cells. One hundred and twenty 180-day-old Kangle yellow roosters were randomly divided into 4 groups with 3 replicates per group and 10 roosters per replicate. After a one-week adaptation period, the roosters were subjected to the following treatments: CON group (control group), fed a basal diet and intraperitoneally injected with 0.9% saline on day 14; DQ group (diquat-induced oxidative stress group), fed a basal diet and intraperitoneally injected with diquat (15 mg/kg BW, dissolved in 0.9% saline) on day 14; SeY+DQ group (SeY pretreatment+diquat induced oxidative stress group), fed an experiment diet which supplemented with 0.5 mg/kg SeY based on the basal diet and intraperitoneally injected with diquat (15 mg/kg BW, dissolved in 0.9% saline) on day 14; SeY group (SeY pretreatment group), fed an experiment diet which supplemented with 0.5 mg/kg SeY based on the basal diet and intraperitoneally injected with 0.9% saline on day 14. The experiment lasted for 18 days. At the end of the experiment, all chickens were euthanized, and small intestinal tissues were collected. The localization of proteins and the expression of proteins and genes of microtubule-associated protein 1 light chain 3β (LC3B), PTEN-induced putative kinase 1 (PINK1), and parkin (Parkin) in the duodenum, jejunum, and ileum were analyzed using immunohistochemistry, Western blot, and real-time quantitative PCR. The results showed as follows: 1) LC3B, PINK1, and Parkin proteins were primarily localized in the cytoplasm of intestinal villus mucosal epithelial cells, intestinal gland epithelial cells, and duodenal gland epithelial cells across all intestinal segments. 2) In the duodenum and jejunum, the relative expression level of LC3B protein in the DQ group was significantly higher than that in the CON and SeY+DQ groups (P<0.05). In the ileum, the relative expression level of LC3B protein was significantly decreased (P<0.05), while the relative expression level of PINK1 protein was significantly increased in the DQ group compared with the CON group (P<0.05). In both the duodenum and jejunum, the relative expression level of PINK1 protein in the SeY group was significantly higher than that in the CON group (P<0.05), and it in the SeY+DQ group was significantly higher than that in the DQ group (P<0.05). In the duodenum, the relative expression level of Parkin protein was significantly lower in the DQ and SeY groups than in the CON group (P<0.05). In the jejunum, compared with the CON group, the relative expression level of Parkin protein was significantly increased in the DQ group (P<0.05) but significantly decreased in the SeY group (P<0.05). 3) In the duodenum, the mRNA relative expression levels of LC3B and PINK1 genes in the DQ group were significantly higher than those in the CON group (P<0.05). The SeY+DQ group showed significantly higher mRNA relative expression levels of LC3B, PINK1 and Parkin genes compared with the DQ group (P<0.05). In the jejunum, the mRNA relative expression levels of LC3B and PINK1 genes in the CON and SeY+DQ groups were significantly higher than those in the DQ group (P<0.05), whereas the mRNA relative expression level of Parkin gene was significantly lower than that in the DQ group (P<0.05). In the ileum, the mRNA relative expression levels of LC3B, PINK1 and Parkin genes in the DQ group were significantly higher than those in the CON and SeY+DQ groups (P<0.05). The above results indicate that diquat treatment can induce an increase in autophagy level in chicken duodenal and jejunal cells, while dietary supplementation with yeast selenium reduces autophagy level, which may be associated with the mitochondrial autophagy PINK1/Parkin pathway.

This study was conducted to investigate the effects of niacin (NA) and nicotinamide (NAM) on oxidative stress and lipid metabolism of hepatocytes induced by non-esterified fatty (NEFA) acid of dairy cows through an in vitro cell model. The experiment treated hepatocytes of dairy cows with different concentrations of NEFA (0, 0.4, 0.8, 1.2, 1.6, 2.0 mmol/L) for 12 h, to select the optimal NEFA concentration for constructing a negative energy balance (NEB) model during the perinatal period. Based on the NEB model constructed at the optimal NEFA concentration, added NA at concentrations of 0, 0.5, 1.0, 2.0, 4.0 and 8.0 mmol/L, as well as NAM at concentrations of 0, 3, 6, 9, 12 and 15 mmol/L, respectively, each concentration set 3 replicates and treated for 12 h. The results showed as follows: 1) compared with the no added NEFA group, the hepatocytes triglyceride (TG) content of 1.2 mmol/L NEFA group was extremely significantly increased (P<0.01), the culture medium lactate dehydrogenase (LDH) activity was significantly increased (P<0.05), and the cell viability was significantly decreased (P<0.05). Therefore, 1.2 mmol/L NEFA was the optimal concentration for constructing the NEB model. 2) Compared with the no added NA or NAM, added 1 mmol/L NA or 9 mmol/L NAM significantly or extremely significantly decreased the activity of LDH in culture medium and content of malondialdehyde (MDA) in hepatocytes (P<0.05 or P<0.01), significantly or extremely significantly increased the content of glutathione (GSH) in hepatocytes (P<0.05 or P<0.01); added 1 mmol/L NA or 10 mmol/L NAM significantly or extremely significantly increased the cell viability (P<0.01). Therefore, 1 mmol/L NA or 10 mmol/L NAM were the optimal treated concentration. 3) Compared with the NEFA, added NA and NAM extremely significantly increased the content of GSH in hepatocytes (P<0.01); compared with the NA, added NAM significantly increased the content of GSH in hepatocytes (P<0.05). Compared with the NEFA, added NA and NAM extremely significantly decreased the content of MDA in hepatocytes (P<0.01); compared with the NAM, added NA significantly decreased the content of MDA in hepatocytes (P<0.05). Compared with the NEFA, added NA extremely significantly increased the mRNA relative expression level of G protein coupled receptor 109A (GPR109A), fatty acid desaturase 2 (FADS2), carnitine palmitoyltransferase 1 (CPT1), peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) and peroxisome proliferator activated receptor α (PPARα) in hepatocytes (P<0.01); compared with the NA, added NAM significantly or extremely significantly decreased the mRNA relative expression level of GPR109A, fFADS2, CPT1, PGC-1α and PPARα in hepatocytes (P<0.05 or P<0.01). Compared with the NEFA, added NA extremely significantly decreased the mRNA relative expression level of diacylglycerol acyltransferase 2 (DGAT2), fatty acid synthase (FASN) and sirtuin 1 (SIRT1) in hepatocytes (P<0.01); compared with the NA, added NAM extremely significantly increased the mRNA relative expression level of DGAT2, FASN and SIRT1 in hepatocytes (P<0.01). In conclusion, both NA and NAM can effectively alleviate lipid deposition in hepatocytes of dairy cows induced by NEFA, but NA has greater potential in comprehensive regulation of lipid metabolism, reduction of oxidative damage and enhancement of cell function.

This experiment aimed to explore whether tea polyphenols could activate silent information regulator 2-related enzyme 3 (SIRT3) to alleviate the inflammatory response in bovine mammary epithelial cells (BMECs) induced by oxidative stress. By interfering with SIRT3, damaging BMECs with hydrogen peroxide (H₂O₂), and then intervening with tea polyphenols (TP), the effect of TP activating SIRT3 on the inflammatory response of oxidatively damaged BMECs was clarified. The results showed that after interfering with SIRT3 and treating with H₂O₂ lead to mitochondrial dysfunction, the mRNA relative expression levels of mitochondrial factors such as nuclear respiratory factor 1 (NRF1), peroxisome proliferator-activated receptor-gamma coactivator-1α (PGC-1α) and mitochondrial transcription factor A (TFAM) were significantly decreased (P<0.01), which in turn caused oxidative stress in cells, the content of malondialdehyde (MDA), an oxidative stress marker in BMECs, and the fluorescence intensity of reactive oxygen species (ROS) were significantly increased (P<0.01), the mRNA relative expression levels of the antioxidant pathway nuclear respiratory factor 2 (NRF2) and heme oxygenase-1 (HO-1) were significantly decreased (P<0.01), the contents of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in BMECs were significantly decreased (P<0.01), the mRNA relative expression levels of inflammatory factors interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-8 (IL-8) were significantly increased (P<0.01), finally, the mRNA relative expression levels of apoptosis factors such as B-cell lymphoma 2-associated X protein (BAX) and cysteine-containing aspartate-specific protease 3 (CASP3) were significantly increased (P<0.01), leading to the apoptosis of BMECs. However, the addition of TP could reverse this reaction, by increasing the contents of antioxidant factors and mitochondrial factors, and inhibiting the expression of inflammatory factors and apoptosis factors, alleviated the oxidative stress and inflammatory response of BMECs induced by H₂O₂. When SIRT3 was knocked out, this inhibitory effect disappeared, and mitochondrial dysfunction and oxidative damage were aggravated. In conclusion, this study reveals the effect and mechanism of TP in alleviating the mitochondrial dysfunction, oxidative stress and inflammatory response of BMECs induced by H₂O₂ through activating SIRT3, providing a solid theoretical and technical support for the popularization and application of TP in dairy cow production.

This study aimed to explore the mechanism of Houttuynia cordata in preventing and treating enteritis using network pharmacology and molecular docking technology. The active components of Houttuynia cordata were obtained through the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) and literature retrieval, the active component targets of Houttuynia cordata and enteritis targets were acquired from the Swiss Target Prediction and GeneCards databases, respectively, and the common targets were obtained. The protein-protein interaction (PPI) network analysis of the common targets was performed using the search tool for the retrieval of interacting genes/proteins (STRING) database, the gene ontology (GO) function and Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analysis were conducted using the database for annotation, visualization and integrated discovery (DAVID). The active components of Houttuynia cordata-enteritis targets-signaling pathways network diagram was constructed using Cytoscape 3.7.1 software, and the molecular docking technology was used to verify the docking of the active components with the core targets. The results showed that Houttuynia cordata contains nine main active components, including isoramanone, kaempferol and quercetin et al, and 90 targets for preventing and treating enteritis were identified, and the core targets were interleukin 6 (IL6), serine/threonine protein kinase 1 (AKT1), tumor necrosis factor (TNF) and epidermal growth factor receptor (EGFR). The GO function enrichment analysis enriched 473 terms, including 347 biological processes, 55 cellular components and 71 molecular functions; the KEGG pathway enrichment analysis enriched 146 terms, primarily involving the phosphatidylinositol 3-kinase (PI3K)-protein kinase B (AKT) and TNF signaling pathways et al. The molecular docking results indicated that the active components of Houttuynia cordata could stably bind to the core targets, with the strongest binding ability observed between isoramanone and EGFR, kaempferol and TNF, quercetin and TNF. In conclusion, the active components of Houttuynia cordata, including isoramanone, kaempferol and quercetin can prevent and treat enteritis by targeting core targets such as IL6, AKT1, TNF and EGFR, and regulating the PI3K-AKT and TNF signaling pathways. This study provides a theoretical basis for the application of Houttuynia cordata in livestock and poultry production.

This study aimed to investigate the effects of dietary resveratrol supplementation on pork quality through Meta-analysis, and to reveal its potential regulatory mechanisms by integrating transcriptome data mining and computational biology approaches. A systematic search was conducted for literature related to the effects of resveratrol on pork quality published in CNKI, Wanfang, Web of Science and Science Direct databases from January 2000 to January 2025. After screening based on inclusion and exclusion criteria, 5 studies were finally included in the Meta-analysis. The results of Meta-analysis showed that compared with the control group, dietary resveratrol supplementation significantly increased the redness value of pork at 45 min post-slaughter (P<0.05), significantly decreased the lightness value of pork at 24 h post-slaughter (P<0.05), and significantly reduced pork drip loss (P<0.05). Further, potential genes associated with pork redness value and drip loss were screened through transcriptome data mining, and intersection analysis was performed with the predicted targets of resveratrol. The results showed that resveratrol may affect pork drip loss by regulating the expression of carbonic anhydrase 2 (CA2), annexin A5 (ANXA5), cysteine-aspartic acid protease 7 (CASP7), 11β-hydroxysteroid dehydrogenase 1 (HSD11B1) and heat shock protein 90 alpha family class A member 1 (HSP90AA1); meanwhile, it may influence pork redness value by regulating the expression of estrogen receptor 1 (ESR1) and CASP7. Molecular docking and molecular dynamics simulations further confirmed that resveratrol has potential binding interactions with the proteins encoded by the aforementioned genes. In conclusion, the improvement effects of dietary resveratrol on pork quality are mainly manifested in increasing redness value, decreasing lightness value and reducing drip loss. The potential targets of resveratrol for regulating pork drip loss are CA2, ANXA5, CASP7, HSD11B1 and HSP90AA1, while the potential targets for regulating pork redness value are ESR1 and CASP7. These findings provide a basis for subsequent studies on the mechanisms underlying resveratrol-mediated regulation of pork quality based on the aforementioned potential targets.

This study aimed to investigate the effects of Clostridium butyricum on intestinal morphology, the expression of inflammation and barrier-related genes, as well as the structure and function of the fungal community in mice challenged with enterotoxigenic Escherichia coli K88 (ETEC K88). Twenty 4-week-old male C57BL/6J mice with similar initial body weight were selected, after one week of acclimatization, they were randomly divided into four groups (5 mice per group): the control group (CON group), the Clostridium butyricum group (CB group), the ETEC K88 group (ETEC group), and the Clostridium butyricum+ETEC K88 group (CB+ETEC group). The experimental period lasted 28 days. During this period, the CON group received a daily oral gavage of 200 μL of physiological saline throughout the entire 28 days; the CB group received a daily oral gavage of 200 μL of a Clostridium butyricum suspension (1×10⁸ CFU/mL) from days 1 to 21, followed by 200 μL of physiological saline from days 22 to 28; the ETEC group received 200 μL of physiological saline daily from days 1 to 21, and was then challenged with a daily oral gavage of 200 μL of an ETEC K88 suspension (1×10⁹ CFU/mL) from days 22 to 28; the CB+ETEC group received a daily oral gavage of 200 μL of the Clostridium butyricum suspension (1×10⁸ CFU/mL) from days 1 to 21, and was then challenged with a daily oral gavage of 200 μL of ETEC K88 suspension (1×10⁹ CFU/mL) from days 22 to 28. The results showed that in the ETEC K88-challenged mice, pretreatment with Clostridium butyricum significantly increased jejunal villus height and the villus height/crypt depth ratio (P<0.05), while significantly reduced the pathological score (P<0.05). It also significantly up-regulated the mRNA relative expression levels of barrier-related genes, including claudin-1 (Claudin-1), zonula occludens-1 (ZO-1), and occludin (Occludin) in the jejunum (P<0.05). Concurrently, it significantly down-regulated the mRNA relative expression levels of inflammation-related genes, namely interleukin-6 (IL-6), interleukin-1β (IL-1β), and tumor necrosis factor-alpha TNF-α (P<0.05). Further analysis of the fungal community diversity and structure in the jejunum and cecum revealed that, in the jejunum, compared with the ETEC group, the CB+ETEC group showed no significant changes in either the Chao1 or Shannon indices (P>0.05), and no obvious difference observed in the fungal community structure. Conversely, in the cecum, the CB+ETEC group exhibited an extremely significant decrease in the Chao1 index compared with the ETEC group (P<0.01), along with a distinct alteration in the fungal community structure. Analysis of differentially fungal genera showed a significant enrichment of potential pathogenic fungi, such as Aspergillus, in the ETEC group. In contrast, pretreatment with Clostridium butyricum reduced the relative abundance of these pathogenic fungi. Furthermore, it led to a significant enrichment of beneficial fungal genera, including Talaromyces and Trichoderma. KEGG-based functional analysis indicated that after pretreatment with Clostridium butyricum, fungal community in the jejunum likely alleviated intestinal damage by activating energy synthesis pathways such as glycolysis/gluconeogenesis and antioxidant/anti-inflammatory pathways like propanoate metabolism, whereas in the cecum, they might enhance functional pathways such as ATP-binding cassette (ABC) transporter expression and flavonoid synthesis to alleviate intestinal damage caused by ETEC K88 infection. In conclusion, Clostridium butyricum mitigates the adverse effects of ETEC K88 challenge on intestinal health in mice by inhibiting the proliferation of pathogenic fungi, promoting the enrichment of beneficial fungi, and thereby regulating specific intestinal microbiota metabolic pathways.

This experiment aimed to investigate the effects of dietary supplementation of crude polysaccharides from Artemisia ordosica or replacing part of corn stover and rice straw with high-quality mixed forage on in vitro rumen fermentation and nutrient degradation in beef cattle, providing a basis for the rational utilization of Artemisia ordosica resources and roughage resources in beef cattle farming. Simmental cattle were selected as donors of rumen fluid. A single-factor completely randomized experimental design was adopted and divided into 7 groups, with 6 replicates in each group. They were continuously cultured in vitro for 24 h. The ratio of concentrate to roughage of the culture substrate was 60∶40. Among them, in the control group (group CON), the ratio of high-quality mixed forage (alfalfa∶oat grass∶Leymus chinensis=4∶3∶3) to low-quality roughage (corn stover∶rice straw=1∶1) in the substrate was 1∶1. In groups Ⅰ to Ⅵ, no high-quality mixed forage was supplemented as the substrate. Groups Ⅰ and Ⅱ were a single corn stover group and a single rice straw group, respectively, and the low-quality roughage in the substrate was either a single corn stover or rice straw. Group Ⅲ was the corn stover+rice straw group, with the ratio of corn stover to rice straw in the substrate being 1∶1. Groups Ⅳ, Ⅴ and Ⅵ were supplemented with 0.050%, 0.075% and 0.100% crude polysaccharides of Artemisia ordosica on the basis of group Ⅲ, respectively. The results showed as follows: 1) compared with groups CON and Ⅵ, the bacterial protein concentration in groups Ⅱ to Ⅳ was significantly decreased (P<0.05), which was the lowest in group Ⅱ; the gas production in groups Ⅰ to Ⅴ showed a decreasing trend (P=0.068). Compared with group CON, the ammonia nitrogen concentration in groups Ⅱ to Ⅵ was significantly decreased (P<0.05), which was the lowest in group Ⅱ. Compared with group CON, the acetate concentration in group Ⅰ was significantly decreased (P<0.05), the concentrations of propionate, butyrate and total volatile fatty acids in groups Ⅰ to Ⅵ were significantly decreased (P<0.05), and the acetate to propionate ratio was significantly increased (P<0.05). Compared with groups CON, Ⅴ and Ⅵ, the degradation rates of dry matter, crude protein and acid detergent fiber in groups Ⅰ to Ⅳ were significantly decreased (P<0.05). Compared with groups CON and Ⅳ, the ether extract degradation rate in the other five groups was significantly decreased (P<0.05). Compared with groups CON and Ⅴ, the neutral detergent fiber degradation rate in groups Ⅰ to Ⅳ was significantly decreased (P<0.05). 3) The multiple-factors associative effects indices (MFAEI) from high to low were group CON, group Ⅵ, group Ⅴ, group Ⅲ, group Ⅳ, groupⅠ and group Ⅱ. In conclusion, dietary supplementation of 0.075% and 0.100% crude polysaccharides of Artemisia ordosica or replacing 50% of the low-quality roughage composed of corn stover and rice straw with high-quality mixed forage composed of alfalfa, oat grass and Leymus chinensis can both improve the utilization efficiency of roughage and promote the in vitro rumen fermentation and nutrient degradation of the diet in beef cattle.

This study aimed to clone the arabinofuranosidase gene α-ara from Ruminococcus flavefaciens and achieve its soluble expression in an Escherichia coli expression system, as well as to investigate the enzymatic properties of its expression product arabinofuranosidase α-Ara. Using the genomic DNA of Ruminococcus flavefaciens as the template, the target gene α-ara was amplified by PCR. The amplified fragment was ligated into the expression vector pET28a to construct the recombinant plasmid pET28a-α-ara, which was then transformed into Escherichia coli BL21(DE3). Expression of the recombinant enzyme was induced by isopropyl β-D-thiogalactopyranoside (IPTG), and the target enzyme was purified by nickel ion affinity chromatography. Bioinformatics analysis and enzymatic characterization were subsequently performed. The results showed that α-Ara had a theoretical molecular mass of 106.87 ku and a predicted isoelectric point of 4.96. It contained a signal peptide sequence, one cellulosomal Dockerin domain and three catalytic domains, belonging to the glycoside hydrolase family 43 (GH43). The optimal pH of α-Ara was 6.0, and it exhibited good stability within the pH range of 6.0 to 9.0. The optimal temperature was 50 ℃, and the enzyme can retain more than 80% of its activity at temperatures≤50 ℃. Metal ions including Mg²⁺, K⁺, Co²⁺, Na⁺, Ba²⁺ and Mn²⁺ significantly activated the enzyme, while Cu²⁺, Ni²⁺ and ethylenediaminetetraacetic acid (EDTA) showed obvious inhibitory effects. Using p-nitrophenyl α-L-arabinofuranoside as the substrate (concentrations of 1.0 to 6.0 mmol/L), the Michaelis constant (K_m) was 5.093 mmol/L, the maximum reaction rate (V_max) was 9.234 μmol/(min·mg), the catalytic constant (k_cat) was 0.632 5 s^-1 and the specific enzyme activity reached 8.760 U/mg. In conclusion, this study successfully cloned and expressed the arabinofuranosidase α-Ara from Ruminococcus flavefaciens. This enzyme has an optimal temperature of 50 ℃ and an optimal pH of 6.0, exhibiting moderate thermal stability, broad pH tolerance (6.0 to 9.0), and responsive activity to various metal ions.

This study aimed to systematically evaluate the degradation characteristics of seven characteristic crop straws (cumin straw, rape straw, Caragana korshinskii, tiger nut straw, cotton straw, millet straw, and licorice straw) in southern Xinjiang, providing a basis for their efficient utilization as feed. Six healthy Duolang sheep with a body weight of (40.00±1.50) kg and equipped with permanent rumen fistulas were selected as rumen fluid donors. The in vitro gas production method was used to determine the 72-hour gas production and gas production parameters of seven kinds of straws. The degradation rates and effective degradation rates of dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), and acid detergent fiber (ADF) in seven kinds of straws at different time points (6, 12, 24, 36, 48 and 72 hours) in rumen were determined by the nylon bag method. The in vitro rumen degradation rates, small intestinal digestibilities and total digestive tract digestibilities of DM and organic matter (OM) in seven kinds of straws were determined by the in vitro three-step method. Finally, a prediction model for the rumen effective degradation rates of nutrients and the total digestive tract digestibility of DM was established using gas production. The results showed as follows: 1) cumin straw had the highest gas production and potential gas production within 72 hours, millet straw had the fastest gas production rate, and Caragana korshinskii had the lowest gas production. 2) At 72 hours, the rumen degradation rate and effective degradation rate (except for licorice straw) of DM in cumin straw were significantly higher than those in the other straws (P<0.05), while those in Caragana korshinskii were the lowest; the rumen degradation rate and effective degradation rate of CP in licorice straw were significantly higher than those in the other straws (P<0.05), while those in tiger nut straw were the lowest; the rumen degradation rate and effective degradation rate of NDF in tiger nut straw were the highest, while those in Caragana korshinskii were the lowest; the rumen degradation rate and effective degradation rate of ADF in tiger nut straw were significantly higher than those in the other straws (P<0.05), while those in rape straw were the lowest. 3) The in vitro rumen degradation rates of DM and OM in cumin straw were significantly higher than those in the other six kinds of straws (P<0.05). The in vitro small intestinal digestibilities of DM in tiger nut straw and licorice straw, as well as OM in licorice straw, were relatively high, while those in Caragana korshinskii were the lowest. The in vitro total digestive tract digestibilities of DM and OM in cumin straw were the highest, while those in Caragana korshinskii were the lowest. There was no significant difference in the in vitro total digestive tract digestibility of DM between millet straw and licorice straw, nor in vitro total digestive tract digestibility of OM among licorice straw, millet straw and cotton straw (P>0.05). 4) The effective degradation rate of DM was significantly positively correlated with the gas production at 12, 48 and 72 hours (P<0.05), and the effective degradation rate of ADF was significantly positively correlated with the gas production at 48 and 72 hours (P<0.05). The in vitro total digestive tract digestibility of DM was significantly positively correlated with the gas production at each time point (P<0.05). When the gas production at 6 hours was used as the predictor of the total digestive tract digestibility of DM, the obtained prediction equation had the highest determination coefficient (R²), and the prediction equation was the total digestive tract digestibility of DM=31.869+1.296×gas production at 6 hours (R²=0.719, P=0.016). In conclusion, the cumin straw exhibits the best overall feeding potential, the tiger nut straw shows superior fiber degradation characteristics, and Caragana korshinskii has the lowest feed value. This study provides data support for the screening and efficient utilization of characteristic straw resources in southern Xinjiang as feed.

The purpose of this experiment was to study the technological conditions of bacteria-enzyme synergetic fermentation of canola meal, and to develop a fermented canola meal for aquaculture application. The canola meal was fermented by complex bacterial of Bacillus pumilus SE5, Lactococcus lactis 17 and Saccharomyces cerevisiae Sa, the contents of fermentation products such as phytic acid, tannin and glucosinolate were synthesis score analysis by single-factor and orthogonal experiments, and optimized the technological conditions such as strain ratio, inoculation amount, solid-liquid ratio and fermentation time; on this basis, the synergistic fermentation experiments of cellulase, pectinase, phytase and protease was carried out to optimize the optimal addition of each enzyme. The results showed as follows: 1) the optimal ratio of fermentation strain of canola meal was Bacillus pumilus SE5∶Saccharomyces cerevisiae Sa∶Lactococcus lactis 17=1∶2∶2; the best fermentation conditions were the inoculation amount of 10%, the fermentation time of 60 h, the solid-liquid ratio of 1∶1.0; the optimal additions of cellulase, pectinase, phytase and protease were 40, 20, 9 and 150 U/g, respectively. 2) Under the best fermentation conditions, the contents of crude protein, acid-gliadin and amino acids in canola meal after fermentation were 50.25%, 13.64% and 35.86%, respectively, which increased by 18.79%, 156.39% and 20.66% compared with that before fermentation, respectively; the contents of phytic acid, tannin and glucosinolate were 2.64%, 1.11% and 17.05 μmol/g, respectively, which decreased by 68.08%, 40.38% and 33.76% than that before fermentation, respectively. In conclusion, the bacteria-enzyme synergetic fermentation can effectively improve the nutritional value of canola meal.

This experiment aimed to investigate the effects of microbial-enzyme synergistic treatment on silage quality and storage protein characteristics of high-moisture corn, providing a reference for alleviating the restrictive effect of starch-protein matrix on rumen digestion in ruminants. The experiment used fully mature corn kernels as raw materials and set up the control group (CON group), the lactic acid bacteria addition group (LB group), the papain addition group (PAP group), and the combined of lactic acid bacteria and papain addition group (LB+PAP group). Among them, the addition amount of lactic acid bacteria (Lentilactobacillus buchneri) was 1×10⁶ CFU/g FM, and the addition amount of papain was 600 U/g FM. There were 3 replicates in each group. Samples were taken after 60 and 180 days of fermentation respectively to determine the fermentation quality, nutrient contents, protein components and secondary structure changes of high-moisture corn. The results showed as follows: 1) at 180 days of fermentation, compared with CON group, the contents of lactic acid and propionic acid in LB+PAP group were significantly increased (P<0.05). 2) The contents of zein and glutenin in each group at 180 days of fermentation were significantly lower than those at 60 days of fermentation (P<0.05), and the contents of zein and glutenin in LB+PAP group were lower at 180 days of fermentation. Meanwhile, with the extension of fermentation time, the contents of neutral detergent insoluble protein, albumin and globulin were significantly decreased (P<0.05), and the ammonia nitrogen content was significantly increased (P<0.05). In addition, the ammonia nitrogen content in LB+PAP group was significantly higher than that in the other groups (P<0.05). 3) Fourier transform infrared spectroscopy analysis revealed that the absorbance of amide band Ⅰ was decreased with the extension of fermentation time, and LB+PAP group had the lowest absorbance at both fermentation time points. Meanwhile, compared with CON group, the β sheet proportion in LB+PAP group was significantly reduced at 60 days of fermentation (P<0.05), and the proportions of β turn at 60 days of fermentation and random coil at 180 days of fermentation were significantly increased (P<0.05). In conclusion, the microbial-enzyme synergistic treatment can promote the degradation of the starch-protein matrix structure, reconstruct the secondary network structure of protein, and improve the silage quality of high-moisture corn.