1 材料与方法
1.1 试验材料
1.2 试验设计与饲养管理
表1 基础饲粮组成及营养水平(风干基础)Table 1 Composition and nutrient levels of basal diets (air-dry basis) % |
| 项目 Items | 1~21日龄 1 to 21 days of age | 22~42日龄 22 to 42 days of age |
|---|---|---|
| 原料Ingredients | ||
| 玉米Corn | 56.49 | 61.42 |
| 大豆油Soybean oil | 2.22 | 3.00 |
| 豆粕Soybean meal | 30.24 | 25.30 |
| 棉籽粕Cottonseed meal | 5.00 | 5.00 |
| 鱼粉Fish meal | 2.43 | 1.98 |
| 磷酸氢钙CaHPO4 | 1.60 | 1.39 |
| 石粉Limestone | 1.16 | 1.10 |
| 蛋氨酸Met | 0.15 | 0.05 |
| 食盐NaCl | 0.30 | 0.35 |
| 胆碱Choline | 0.19 | 0.19 |
| 预混料Premix1) | 0.22 | 0.22 |
| 合计Total | 100.00 | 100.00 |
| 营养成分Nutrient levels2) | ||
| 代谢能ME/(MJ/kg) | 12.12 | 12.54 |
| 粗蛋白质CP | 21.00 | 19.00 |
| 赖氨酸Lys | 1.12 | 0.98 |
| 蛋氨酸+半胱氨酸Met+Cys | 0.84 | 0.68 |
| 钙Ca | 1.00 | 0.90 |
| 有效磷AP | 0.30 | 0.30 |
1)预混料为每千克饲粮提供 Premix provided the following per kg of diets:Fe 80 mg,Mn 80 mg,Zn 80 mg,Cu 8 mg,I 0.35 mg,Se 0.15 mg,VA 12 000 IU,VD3 3 000 IU,VE 30 IU,VK3 1 mg,VB1 2 mg,VB2 6 mg,泛酸 pantothenic acid 9 mg,吡哆醇 pyridoxine 5 mg,烟酸 niacin 30 mg,VB12 0.01 mg,生物素 biotin 0.10 mg,叶酸 folic acid 0.30 mg。 2)营养水平为计算值。Nutrition levels were calculated values. |
1.3 样品采集与分析
1.3.1 样品采集
1.3.2 生长性能指标的测定
1.3.3 肠道黏膜免疫和抗氧化指标的测定
1.3.4 肠道屏障、抗氧化以及细胞凋亡相关基因表达的测定
1.3.4.1 空肠总RNA提取与逆转录
1.3.4.2 实时荧光定量PCR(RT-qPCR)
表2 实时荧光定量PCR引物Table 2 Primers for RT-qPCR |
| 基因 Genes | 引物序列 Primer sequence (5'—3') | 目的基因片段 Target gene fragment/bp | 退火温度 Anealing temperature/℃ |
|---|---|---|---|
| β-肌动蛋白β-actin | F:GTCCACCGCAAATGCTTCTA R:AGCCATGCCAATCTCCGTCTT | 154 | 60 |
| 黏蛋白2 MUC2 | F:AATGCTGAGTTCTTGCCTAA R:TGTTGCAGTTCATATCCTGGT | 155 | 60 |
| 闭合蛋白Occludin | F:CTGCTCTGCCTCATCTGCTTCTTC R:CCATCCGCCACGTTCTTCACC | 143 | 60 |
| 封闭蛋白-1 Claudin-1 | F:ACCCACAGCCTAAGTGCTTC R:AGGTCTCATAAGGCCCCACT | 200 | 60 |
| 闭锁小带蛋白-1 ZO-1 | F:GCGCCTCCCTATGAGGAGCA R:CAAATCGGGGTTGTGCCGGA | 160 | 65 |
| 半胱天冬酶-3 Caspase-3 | F:AAAGATGGACCACGCTCAGG R:TCCGGTATCTCGGTGGAAGT | 189 | 65 |
| Bcl-2相关X蛋白Bax | F:CGCAAGGTCTACGCCATCATCTC R:GCAGCAGACCAGCACCAAGTAG | 165 | 65 |
| B淋巴细胞瘤-2 Bcl-2 | F:GAGTTCGGCGGCGTGATGTG R:TTCAGGTACTCGGTCATCCAGGTG | 92 | 65 |
| 核因子E2相关因子2 Nrf2 | F:ACGCTTTCTTCAGGGGTAGC R:GTTCGGTGCAGAAGAGGTGA | 170 | 60 |
| 血红素加氧酶-1 HO-1 | F:GCTGGGAAGGAGAGTGAGAGGAC R:GCGACTGTGGTGGCGATGAAG | 107 | 60 |
1.4 数据统计与分析
2 结果与分析
2.1 复合益生菌对肉鸡生长性能的影响
表3 复合益生菌对肉鸡生长性能的影响Table 3 Effects of compound probiotics on growth performance of broilers |
| 项目 Items | 对照组 Control group | 益生菌Ⅰ组 Probiotics group Ⅰ | 益生菌Ⅱ组 Probiotics group Ⅱ | 益生菌Ⅲ组 Probiotics group Ⅲ | 均值标准误 SEM | P值 P-value |
|---|---|---|---|---|---|---|
| 1~21日龄1 to 21 days of age | ||||||
| 平均日增重ADG/g | 20.79b | 22.73a | 21.97a | 22.59a | 0.53 | 0.01 |
| 平均日采食量ADFI/g | 40.85 | 40.49 | 40.84 | 41.53 | 1.84 | 0.61 |
| 料重比F/G | 1.98 | 1.78 | 1.86 | 1.84 | 0.11 | 0.12 |
| 22~42日龄22 to 42 days of age | ||||||
| 平均日增重ADG/g | 48.82b | 53.89a | 52.44a | 52.60a | 1.56 | 0.03 |
| 平均日采食量ADFI/g | 98.92 | 99.32 | 100.12 | 100.34 | 3.35 | 0.70 |
| 料重比F/G | 2.03 | 1.85 | 1.91 | 1.91 | 0.08 | 0.05 |
同行数据肩标字母不同表示差异有统计学意义(P<0.05)。下表同。 | |
Values with different superscript letters in the same row indicated that the difference was statistically significant (P<0.05). The same as below. |
2.2 复合益生菌对肉鸡肠道黏膜免疫指标的影响
表4 复合益生菌对肉鸡肠道黏膜免疫球蛋白含量的影响Table 4 Effects of compound probiotics on immunoglobulin contents in intestinal mucosa of broilers μg/mg prot |
| 项目 Items | 对照组 Control group | 益生菌Ⅰ组 Probiotics group Ⅰ | 益生菌Ⅱ组 Probiotics group Ⅱ | 益生菌Ⅲ组 Probiotics group Ⅲ | 均值标准误 SEM | P值 P-value |
|---|---|---|---|---|---|---|
| 21日龄21 days of age | ||||||
| 免疫球蛋白A IgA | 1.764c | 2.154b | 2.221ab | 2.376a | 0.093 | 0.001 |
| 免疫球蛋白G IgG | 9.733b | 12.371a | 12.205a | 12.851a | 0.500 | 0.001 |
| 42日龄42 days of age | ||||||
| 免疫球蛋白A IgA | 2.268c | 2.702a | 2.404bc | 2.457b | 0.066 | 0.001 |
| 免疫球蛋白G IgG | 12.455 | 12.109 | 13.190 | 12.558 | 0.940 | 0.714 |
表5 复合益生菌对肉鸡肠道黏膜免疫因子含量的影响Table 5 Effects of compound probiotics on immune factor contents in intestinal mucosa of broilers pg/mg prot |
| 项目 Items | 对照组 Control group | 益生菌Ⅰ组 Probiotics group Ⅰ | 益生菌Ⅱ组 Probiotics group Ⅱ | 益生菌Ⅲ组 Probiotics group Ⅲ | 均值标准误 SEM | P值 P-value |
|---|---|---|---|---|---|---|
| 21日龄21 days of age | ||||||
| 白细胞介素-2 IL-2 | 1.445c | 1.776b | 1.809b | 2.364a | 0.068 | 0.001 |
| 白细胞介素-10 IL-10 | 0.430c | 0.496b | 0.527ab | 0.575a | 0.030 | 0.001 |
| 42日龄42 days of age | ||||||
| 白细胞介素-2 IL-2 | 1.429c | 1.622bc | 2.109a | 1.905ab | 0.154 | 0.001 |
| 白细胞介素-10 IL-10 | 0.433c | 0.537b | 0.618a | 0.538ab | 0.030 | 0.001 |
2.3 复合益生菌对肉鸡肠道屏障相关基因表达的影响
图1 复合益生菌对肠道屏障相关基因表达的影响a~d分别展示的是21日龄肉鸡空肠MUC2、occludin、ZO-1与claudin-1 mRNA的相对表达量,e~h分别展示的是42日龄肉鸡空肠MUC2、occludin、ZO-1与claudin-1 mRNA的相对表达量。结果以平均值±标准差表示,数据柱上标不同字母表示差异显著(P<0.05),下图同。 Fig.1 Effects of compound probiotics on intestinal barrier related genes expression of broilers a to d showed the relative expression levels of MUC2, occludin, ZO-1 and claudin-1 mRNA in jejunum of broilers at 21 days of age, respectively, and e to h showed the relative expression levels of MUC2, occludin, ZO-1 and claudin-1 mRNA in jejunum of broilers at 42 days of age, respectively. The results were expressed as mean±SD, different letters on the data columns indicated that the difference was significant (P<0.05), the same as below. |
2.4 复合益生菌对肉鸡肠道抗氧化指标及抗氧化相关基因表达的影响
图2 复合益生菌对肠道抗氧化指标及抗氧化相关基因表达的影响a~e分别展示的是21日龄肉鸡空肠T-AOC、SOD和GSH-Px活性与Nrf2、HO-1 mRNA的相对表达量,A~E分别展示的是42日龄肉鸡空肠T-AOC、SOD和GSH-Px活性与Nrf2、HO-1 mRNA的相对表达量。 Fig.2 Effects of compound probiotics on intestinal antioxidant indexes and antioxidant-regulated genes expression of broilers a to e showed the T-AOC, SOD and GSH-Px activities and the relative expression levels of Nrf2, HO-1 mRNA in jejunum of broilers at 21 days of age, respectively, and A to E showed the T-AOC, SOD and GSH-Px activities and the relative expression levels of Nrf2, HO-1 mRNA in jejunum of broilers at 42 days of age, respectively. |
2.5 复合益生菌对肉鸡肠道细胞凋亡的影响
图3 复合益生菌对肠道细胞凋亡相关基因表达的影响a~c分别展示的是21日龄肉鸡空肠Bax、Bcl-2与Caspase-3 mRNA的相对表达量,d~f分别展示的是42日龄肉鸡空肠Bax、Bcl-2与Caspase-3 mRNA的相对表达量。 Fig.3 Effects of compound probiotics on intestinal apoptosis-related gene expression of broilers a to c showed the relative expression levels of Bax, Bcl-2 and Caspase-3 mRNA in jejunum of broilers at 21 days of age, respectively, and d to f showed the relative expression levels of Bax, Bcl-2 and Caspase-3 mRNA in jejunum of broilers at 42 days of age, respectively. |
