Chinese Journal of Animal Nutrition >

2024 , Vol. 36 >Issue 11: 7250 - 7261

DOI: https://doi.org/10.12418/CJAN2024.617

RESEARCH PAPER

Effects of Different Dietary Whole Plant Forage Mulberry Addition Ratios on Growth Performance, Slaughter Performance, Meat Quality, Serum Antioxidant Indices and Nutrient Apparent Digestibility of Chuanbai Rex Rabbits

  • WANG Honglin , 1, 2 ,
  • FU Xiangchao 3 ,
  • ZUO Yanchun 1, 2 ,
  • ZHANG Kai 3 ,
  • WU Zizhou 1, 2 ,
  • YAN Xu 1, 2 ,
  • XIAO Lian 4 ,
  • CHEN Hui 4 ,
  • KOU Jing 1, 2 ,
  • WEN Bin , 3, * ,
  • DU Zhouhe , 1, 2, *
Expand
  • 1 Forage Crops Germplasm Enhancement and Production Management Key Laboratory of Nanchong City, Sericulture Research Institute, Sichuan Academy of Agricultural Sciences, Nanchong 637000, China
  • 2 Institute of Special Economic Animals and Plants, Sichuan Academy of Agricultural Sciences, Nanchong 637000, China
  • 3 Sichuan Academy of Grassland Science, Chengdu 611430, China
  • 4 Nanchong Bureau of Agricultural and Rural Affairs, Nanchong 637000, China
* WEN Bin, associate professor, E-mail: ;
DU Zhouhe, associate professor, E-mail:

Received date: 2024-05-22

  Online published: 2024-11-09

Fold

Abstract

This experiment was conducted to investigate the effects of different dietary whole plant forage mulberry addition ratios on growth performance, slaughter performance, meat quality, serum antioxidant indices and nutrient apparent digestibility of Chuanbai Rex rabbits, and to determine the appropriate addition ratio of forage mulberry as a non-conventional feed fiber source in the diet for Chuanbai Rex rabbits. A total of 150 Chuanbai Rex rabbits of 35-day-old with good health, similar body weight and similar genetic background (half male and half female) were randomly divided into 5 groups with 30 replicates per group and 1 rabbit per replicate. Rabbits in the control group were fed a basal diet, and those in the experimental groups were fed the basal diet supplemented with 6%, 12%, 18% and 24% forage mulberry, respectively. The pre-trial period lasted for 7 days and the experimental period lasted for 32 days. The results showed as follows: 1) different dietary ratios of whole plant forage mulberry had no significant effects on the final body weight and average daily gain of Chuanbai Rex rabbits (P>0.05). Compared with the control group, the average daily feed intake in experimental groups was significantly decreased (P<0.05), but there was no significant difference among experimental groups (P>0.05); the ratio of feed to gain in 6% and 24% addition groups was significantly decreased (P<0.05). 2) The eviscerated ratio and semi-eviscerated ratio of Chuanbai Rex rabbits showed a trend of decreasing first and then increasing with the increase of forage mulberry addition ratio. Compared with the control group, there were no significant differences in the eviscerated ratio and semi-eviscerated ratio in experimental groups (P>0.05), but the eviscerated ratio and semi-eviscerated ratio in 24% addition group were significantly higher than those in 18% addition group (P<0.05). Compared with the control group, the spleen index in 12% addition group was significantly increased (P<0.05); the heart index in 12% addition group was significantly higher than that in 6% addition group (P<0.05). 3) Different dietary ratios of whole plant forage mulberry had no significant effects on the drip loss ratio and cooked meat ratio in muscle of Chuanbai Rex rabbits (P>0.05), but significantly increased the crude protein content in muscle (P<0.05), and significantly decreased the ether extract content in muscle (P<0.05). 4) Compared with the control group, the serum total antioxidant capacity of Chuanbai Rex rabbits in 24% addition group was significantly increased (P<0.05), the serum catalase activity in experimental groups was significantly increased (P<0.05), and the serum total bile acid content in 12%, 18% and 24% addition groups was significantly decreased (P<0.05). 5) The apparent digestibility of each nutrient showed a trend of increasing first and then decreasing with the increase of forage mulberry addition ratio. Compared with the control group, the apparent digestibilities of dry matter, crude protein, neutral detergent fiber, acid detergent fiber, ether extract and crude ash in 12% addition group were significantly increased (P<0.05). In conclusion, different dietary whole plant forage mulberry addition ratios have no adverse effects on growth performance and slaughter performance of Chuanbai Rex rabbits, but can increase the muscle crude protein content and decrease the muscle ether extract content; the antioxidant capacity and nutrient apparent digestibility of Chuanbai Rex rabbits can be improved by adding the appropriate ratio of whole plant forage mulberry in diet; under the experimental conditions, the appropriate ratio of whole plant forage mulberry in diet for Chuanbai Rex rabbits is 12%.

Key words： whole plant forage mulberry; Chuanbai Rex rabbits; growth performance; slaughter performance; meat quality; antioxidant capacity; nutrient apparent digestibility

Cite this article

WANG Honglin , FU Xiangchao , ZUO Yanchun , ZHANG Kai , WU Zizhou , YAN Xu , XIAO Lian , CHEN Hui , KOU Jing , WEN Bin , DU Zhouhe . Effects of Different Dietary Whole Plant Forage Mulberry Addition Ratios on Growth Performance, Slaughter Performance, Meat Quality, Serum Antioxidant Indices and Nutrient Apparent Digestibility of Chuanbai Rex Rabbits[J]. Chinese Journal of Animal Nutrition, 2024 , 36(11) : 7250 -7261 . DOI: 10.12418/CJAN2024.617

苜蓿作为草食动物优质的纤维和蛋白质来源,一直以来都是獭兔饲粮中不可或缺的主要原料[1]。不过,我国南方地区由于夏季高温多湿,苜蓿产量和品质均不如我国北方苜蓿主产区,大宗的苜蓿需求均依赖于从北方采购,而且苜蓿价格较高,这显著增加了养殖成本,因此寻找新的可替代优质草粉资源对于獭兔业发展迫在眉睫[2]。饲料桑是近年来备受关注的高蛋白质饲用作物,其不仅营养价值与苜蓿相当[3],富含的多种生物活性物质还在提高动物机体免疫力以及改善畜禽产品的品质和风味等方面具有重要作用[4]。目前已有饲料桑在兔养殖方面的相关报道。孙海涛等[5]研究表明,饲粮中添加适宜比例的饲料桑对育肥期莱芜黑兔生长性能、屠宰性能和肉品质均无明显不良影响,且能提高兔肉中粗蛋白质(CP)、半胱氨酸和缬氨酸含量。陈亚迎等[6]研究表明,饲粮中添加12%~18%饲料桑可一定程度上改善肉兔屠宰性能和器官发育,同时还可显著改善肉品质。石艳华等[7]用桑叶粉替代玉米豆粕饲喂肉兔,结果表明桑叶配合饲料对肉兔有明显的增重效果。王崇洲等[8]研究了饲料桑茎叶粉对肉兔生长性能、血清生化指标和肉品质的影响,结果表明饲粮中添加10%~15%饲料桑茎叶粉能提高兔肉中风味物质含量,改善肉品质。然而,饲料桑是否可以作为苜蓿草粉替代品用于川白獭兔养殖,适宜的添加比例尚不清楚。鉴于此,本试验旨在研究饲粮中添加不同比例的全株饲料桑对川白獭兔生长性能、屠宰性能、肉品质、血清抗氧化指标及养分表观消化率的影响,为饲料桑在川白獭兔养殖中的应用提供参考。

1 材料与方法

1.1 试验材料

本试验所用的饲料桑原料为四川省农业科学院蚕业研究所(四川省农业科学院特种经济动植物研究所)选育的饲料桑新品种“川饲桑1号”,于株高90~100 cm时全株刈割后经65 ℃烘干粉碎后制得。其主要营养成分含量为:干物质(DM)88.78%,CP 18.31%,中性洗涤纤维(NDF)40.04%,酸性洗涤纤维(ADF)22.93%,粗脂肪(EE)1.47%,粗灰分(Ash)10.65%,钙(Ca)2.11%,总磷(TP)0.71%。
试验动物为川白獭兔,由四川省草原科学研究院草食家畜研究所提供,并在其成都市大邑县獭兔科研基地进行试验。动物试验方案经过四川省草原科学研究院审核,符合动物保护和动物福利原则以及国家动物福利伦理的相关规定(审核编号:2023002)。

1.2 试验设计

选取35日龄、健康状况良好、体重相近以及遗传背景相似的川白獭兔150只(公母各占1/2),随机分为5组,每组30个重复,每个重复1只。对照组饲喂基础饲粮,试验组分别在基础饲粮中添加6%、12%、18%和24%饲料桑。预试期7 d,正试期32 d。
对饲粮原料进行常规营养成分含量测定后,参考《肉兔营养需要量》(NY/T 4049—2021)[9]配制饲粮,饲粮为直径为5 mm的颗粒饲料。饲粮组成及营养水平见表1。
表1 饲粮组成及营养水平(风干基础)

Table 1 Composition and nutrient levels of diets (air-dry basis) %

项目
Items		 饲料桑添加比例Forage mulberry addition ratios/%
0(对照Control) 6 12 18 24
原料Ingredients
玉米Corn 18.00 18.00 20.00 20.00 23.00
麸皮Wheat bran 13.00 11.00 8.00 8.00 4.00
豆粕Soybean meal 17.00 16.00 16.00 15.00 16.00
苜蓿Alfalfa 45.00 44.00 39.00 36.00 28.00
砻糠Rice chaff 6.00 4.00 4.00 2.00 4.00
饲料桑Forage mulberry 6.00 12.00 18.00 24.00
预混料Premix1) 1.00 1.00 1.00 1.00 1.00
合计Total 100.00 100.00 100.00 100.00 100.00
营养水平Nutrient levels2)
消化能DE/(MJ/kg) 9.49 9.45 9.47 9.49 9.51
粗蛋白质CP 15.95 15.79 15.80 15.74 15.96
淀粉Starch 14.93 14.63 15.33 15.26 16.35
粗纤维CF 19.06 19.30 19.35 19.18 19.32
中性洗涤纤维NDF 33.22 33.48 32.91 33.06 32.04
酸性洗涤纤维ADF 22.10 22.80 22.92 23.13 23.00
酸性洗涤木质素ADL 3.79 3.66 3.51 3.53 3.57
半纤维素Hemicellulose 11.12 10.68 10.00 9.93 9.04
粗灰分Ash 7.09 7.24 7.22 7.26 7.17
粗脂肪EE 2.34 2.82 3.28 3.78 4.23
钙Ca 1.03 1.04 1.06 1.05 1.06
总磷TP 0.50 0.49 0.49 0.49 0.52
赖氨酸Lys 0.84 0.85 0.83 0.86 0.85
蛋氨酸+胱氨酸Met+Cys 0.65 0.64 0.63 0.65 0.64

1)预混料可为每千克饲粮提供 The premix provided the following per kg of diets:Fe (as ferrous sulfate) 40 mg,Cu (as copper sulfate) 30 mg,Zn (as zinc sulfate) 20 mg,Mn (as manganese sulfate) 10 mg,Mg (as magnesium sulfate) 20 mg,NaCl 4 000 mg,VA 900 IU,VD3 600 IU,VE 60 IU,地克珠利 diclazuril 10 mg。

2)消化能、赖氨酸和蛋氨酸+胱氨酸为计算值,其余为实测值。消化能参考欧洲EGRAN数据库计算,赖氨酸和蛋氨酸+胱氨酸依据开放型饲料配方软件WUFFDA(家兔适用版本)计算。DE, Lys and Met+Cys were calculated values, while the others were measured values. DE was calculated with reference to the European EGRAN database, and Lys and Met+Cys were calculated based on the open feed formula software WUFFDA (applicable to rabbits).

1.3 饲养管理

饲养管理和免疫程序采用常规方法,试验期间肉兔自由采食和饮水。试验结束前7 d,采用内源指示剂法测定养分表观消化率。

1.4 测定指标及方法

1.4.1 饲粮营养成分含量

饲粮CP、淀粉、粗纤维(CF)、NDF、ADF、酸性洗涤木质素(ADL)、半纤维素、Ash、EE、Ca和TP含量分别参照GB/T 6432—2018、GB/T 20194—2018、GB/T 6434—2022、GB/T 20806—2022、NY/T 1459—2022、GB/T 20805—2006、NY/T 3494—2019、GB/T 6438—2007、GB/T 6433—2006、GB/T 6436—2018和GB/T 6437—2018的方法进行测定。

1.4.2 生长性能

试验开始和结束时对所有试验兔进行空腹(禁食12 h,自由饮水)称重,记为初始体重(IBW)和终末体重(FBW),并计算平均日增重(ADG);试验期间记录每只兔的采食量,计算平均日采食量(ADFI),并计算料重比(F/G)。

1.4.3 屠宰性能

试验结束时,每组选取8只接近平均体重的试验兔记录屠宰前体重(活体重),屠宰后将血放干,称量胴体重、全净膛重和半净膛重,计算全净膛率和半净膛率;然后,迅速剥离各脏器(肝脏、脾脏、胸腺和心脏),分别称重,计算脏器指数和器官指数。计算公式为:
全净膛率(%)=(全净膛重/活体重)×100;
半净膛率(%)=(半净膛重/活体重)×100;
脏器指数(%)=(脏器重量/活体重)×100;
器官指数(%)=肝脏指数+脾脏指数+胸腺指数+心脏指数。

1.4.4 肉品质

参照陈亚迎等[6]的方法测定肉品质指标。

1.4.5 血清抗氧化指标

试验结束时,每组选取8只接近平均体重的试验兔进行心脏采血(10 mL/只),将采集的血液静置30 min后于1 230.47×g下离心15 min,分离血清后置于-20 ℃保存。采用全自动生化分析仪(Beckman CX4)测定血清超氧化物歧化酶(superoxide dismutase,SOD)和过氧化氢酶(catalase,CAT)活性、总抗氧化能力(total antioxidant capacity,T-AOC)以及丙二醛(malondialdehyde,MDA)和总胆汁酸(total bile acid,TBA)含量,测定试剂盒购自南京建成生物工程研究所。

1.4.6 养分表观消化率

利用ADL作为内源指示剂计算饲粮中各养分表观消化率,计算公式为:
某养分表观消化率(%)=[1-(粪中某养分含量×饲粮中ADL含量/饲粮中某养分含量×粪中ADL含量)]×100。

1.5 数据统计分析

试验数据采用Excel 2021软件进行初步整理,然后采用SPSS 22.0软件进行单因素方差分析(one-way ANOVA),并采用Duncan氏法进行多重比较。结果数据采用“平均值±标准误”形式表示,P<0.05表示差异显著。

2 结果

2.1 饲粮中添加不同比例全株饲料桑对川白獭兔生长性能的影响

由表2可知,川白獭兔ADG随着饲料桑添加比例的提高呈现先降低后升高的变化趋势,其中12%和18%添加组下降较明显,24%添加组出现回升,但各组间ADG均无显著差异(P>0.05)。与对照组相比,各试验组ADFI均显著降低(P<0.05),但各试验组间均无显著差异(P>0.05)。F/G随着饲料桑添加比例的提高呈现先升高后降低的变化趋势,其中6%和24%添加组F/G显著低于对照组(P<0.05),12%和18%添加组F/G与对照组相比无显著差异(P>0.05)。
表2 饲粮中添加不同比例全株饲料桑对川白獭兔生长性能的影响

Table 2 Effects of different dietary whole plant forage mulberry addition ratios on growth performance of Chuanbai Rex rabbits

项目
Items		 饲料桑添加比例Forage mulberry addition ratios/% P值
P-value
0(对照Control) 6 12 18 24
初始体重
IBW/g		 1 185.00±24.07 1 117.00±25.11 1 134.83±22.94 1 148.00±38.96 1 079.17±25.76 0.107
终末体重
FBW/g		 2 394.67±37.25 2 310.33±48.45 2 282.33±42.01 2 331.33±44.28 2 269.67±32.64 0.228
平均日增重
ADG/(g/d)		 40.72±0.85 40.53±1.22 37.80±0.88 37.80±0.88 40.07±1.04 0.071
平均日采食量
ADFI/(g/d)		 158.76±5.32a 149.20±4.51b 142.98±7.22b 146.91±4.68b 145.53±8.15b 0.015
料重比F/G 3.89±0.32a 3.68±0.21b 3.78±0.18a 3.88±0.35a 3.63±0.29b 0.025

同行数据肩标无字母或相同字母表示差异不显著(P>0.05),不同字母表示差异显著(P<0.05)。下表同。

In the same row, values with no letter or the same letter superscripts mean no significant difference (P>0.05), while with different letter superscripts mean significant difference (P<0.05). The same as below.

2.2 饲粮中添加不同比例全株饲料桑对川白獭兔屠宰性能的影响

由表3可知,各组间川白獭兔屠宰前体重均无显著差异(P>0.05)。川白獭兔全净膛率和半净膛率随着饲料桑添加比例的提高呈现先降低后升高的变化趋势;与对照组相比,各试验组全净膛率和半净膛率均无显著差异(P>0.05),但24%添加组全净膛率和半净膛率显著高于18%添加组(P<0.05)。与对照组相比,12%添加组脾脏指数显著提高(P<0.05),其他试验组脾脏指数均无显著差异(P>0.05)。与对照组相比,各试验组心脏指数均无显著差异(P>0.05),但12%组心脏指数显著高于6%添加组(P<0.05)。各组间器官指数、胸腺指数和肝脏指数均无显著差异(P>0.05)。
表3 饲粮中添加不同比例全株饲料桑对川白獭兔屠宰性能的影响

Table 3 Effects of different dietary whole plant forage mulberry addition ratios on slaughter performance of Chuanbai Rex rabbits

项目
Items		 饲料桑添加比例Forage mulberry addition ratios/% P值
P-value
0(对照Control) 6 12 18 24
屠宰前体重
Pre-slaughter
weight/g		 2 336.67±16.97 2 286.67±31.59 2 246.33±26.6 2 357.33±41.89 2 326.67±13.69 0.288
全净膛率
Eviscerated
ratio/%		 47.39±0.51ab 46.78±0.28ab 46.21±0.56ab 45.82±0.52b 47.89±0.92a 0.018
半净膛率
Semi-eviscerated
ratio/%		 53.57±0.57ab 53.32±0.34ab 52.77±0.55ab 52.38±0.54b 54.68±1.02a 0.014
器官指数
Organ index/%		 4.42±0.14 4.68±0.25 4.83±0.26 4.68±0.13 4.41±0.13 0.167
胸腺指数
Thymus
index/%		 0.26±0.02 0.28±0.02 0.26±0.01 0.28±0.02 0.26±0.01 0.661
肝脏指数
Liver index/%		 3.85±0.14 4.10±0.26 4.22±0.18 4.07±0.10 3.83±0.11 0.380
脾脏指数
Spleen index/%		 0.05±0.00b 0.06±0.01ab 0.08±0.01a 0.07±0.01ab 0.06±0.01ab 0.005
心脏指数
Heart index/%		 0.26±0.01ab 0.24±0.01b 0.27±0.01a 0.26±0.00ab 0.26±0.01ab 0.002

2.3 饲粮中添加不同比例全株饲料桑对川白獭兔肉品质的影响

由表4可知,各组间川白獭兔肌肉滴水损失率和熟肉率均无显著差异(P>0.05)。与对照组相比,12%和24%添加组肌肉DM含量显著降低(P<0.05),6%和18%添加组肌肉DM含量无显著差异(P>0.05);各试验组肌肉CP含量均显著提高(P<0.05),且24%添加组肌肉CP含量最高,显著高于其他试验组(P<0.05);各试验组肌肉EE含量均显著降低(P<0.05),且肌肉EE含量随着饲料桑添加比例的提高呈现逐渐降低的变化趋势;24%添加组肌肉Ash含量显著提高(P<0.05),其他试验组肌肉Ash含量均无显著差异(P>0.05)。
表4 饲粮中添加不同比例全株饲料桑对川白獭兔肉品质的影响

Table 4 Effects of different dietary whole plant forage mulberry addition ratios on meat quality of Chuanbai Rex rabbits %

项目
Items		 饲料桑添加比例Forage mulberry addition ratios/% P值
P-value
0(对照Control) 6 12 18 24
滴水损失率
Drip loss ratio		 37.27±0.62 36.07±0.72 35.99±1.29 36.97±1.16 37.03±0.76 0.767
熟肉率
Cooked meat ratio		 62.73±0.62 63.93±0.72 64.01±1.29 63.03±1.16 62.97±0.76 0.532
干物质DM 24.90±0.07a 24.56±0.07a 23.47±0.16b 24.40±0.20a 23.63±0.27b <0.001
粗蛋白质CP 82.79±0.59e 87.99±0.39c 89.25±0.30b 85.84±0.26d 90.87±0.34a <0.001
粗脂肪EE 9.04±0.07a 4.48±0.04b 3.64±0.16c 3.55±0.10c 3.28±0.10d <0.001
粗灰分Ash 6.26±0.11b 6.39±0.12ab 6.22±0.06b 6.40±0.11ab 6.49±0.07a 0.037

2.4 饲粮中添加不同比例全株饲料桑对川白獭兔血清抗氧化指标的影响

由表5可知,与对照组相比,24%添加组川白獭兔血清T-AOC显著提高(P<0.05),其他试验组血清T-AOC无显著差异(P>0.05);各试验组血清CAT活性均显著提高(P<0.05),且血清CAT活性随着饲料桑添加比例的提高呈现先升高后降低的变化趋势,以12%添加组最高;12%、18%和24%添加组血清TBA含量显著降低(P<0.05)。各组间血清SOD活性和MDA含量均无显著差异(P>0.05)。
表5 饲粮中添加不同比例全株饲料桑对川白獭兔血清抗氧化指标的影响

Table 5 Effects of different dietary whole plant forage mulberry addition ratios on serum antioxidant indices of Chuanbai Rex rabbits

项目
Items		 饲料桑添加比例Forage mulberry addition ratios/% P值
P-value
0(对照Control) 6 12 18 24
超氧化物歧化酶
SOD/(U/mL)		 21.21±0.27 21.39±0.57 21.59±0.50 21.11±0.52 21.20±0.39 0.164
总抗氧化能力
T-AOC/(U/mL)		 8.94±1.98b 8.76±0.81b 10.34±0.94ab 11.92±0.76ab 13.14±0.72a <0.001
丙二醛
MDA/(μmol/L)		 17.77±0.60 17.68±0.79 17.45±4.01 16.82±0.71 16.70±1.07 0.435
过氧化氢酶
CAT/(U/mL)		 8.20±1.16c 15.96±2.28ab 16.45±0.90a 15.04±1.89ab 11.53±0.42b <0.001
总胆汁酸
TBA/(μmol/L)		 19.11±3.03a 12.66±3.13ab 9.94±0.85bc 5.05±1.17c 7.68±0.40bc <0.001

2.5 饲粮中添加不同比例全株饲料桑对川白獭兔养分表观消化率的影响

由表6可知,各养分表观消化率随着饲料桑添加比例的提高总体呈现先升高后降低的变化趋势。与对照组相比,12%、18%和24%添加组DM表观消化率显著提高(P<0.05),且12%添加组DM表观消化率最高,显著高于除18%添加组外的其他试验组(P<0.05);12%添加组CP和ADF表观消化率显著提高(P<0.05),且显著高于其他试验组(P<0.05);12%、18%和24%添加组NDF表观消化率显著提高(P<0.05),且12%添加组NDF表观消化率最高,显著高于其他试验组(P<0.05);各试验组EE表观消化率显著提高(P<0.05),且12%添加组EE表观消化率最高,显著高于除24%添加组外的其他试验组(P<0.05);12%、18%和24%添加组Ash表观消化率显著提高(P<0.05),且18%添加组Ash表观消化率显著高于其他试验组(P<0.05),同时12%添加组Ash表观消化率显著高于6%和24%添加组(P<0.05)。
表6 饲粮中添加不同比例全株饲料桑对川白獭兔养分表观消化率的影响

Table 6 Effects of different dietary whole plant forage mulberry addition ratios on nutrient apparent digestibility of Chuanbai Rex rabbits %

项目
Items		 饲料桑添加比例Forage mulberry addition ratios/% P值
P-value
0(对照Control) 6 12 18 24
干物质DM 69.43±2.10c 70.88±3.87c 78.88±2.72a 77.88±3.34a 75.73±2.42b 0.024
粗蛋白质CP 79.66±1.66b 76.46±2.84c 82.08±1.22a 80.35±1.02b 73.92±2.14d 0.005
中性洗涤纤维NDF 39.25±3.14d 31.16±1.95e 52.57±1.32a 48.32±1.58b 45.20±3.67c 0.001
酸性洗涤纤维ADF 29.54±4.19b 30.12±4.73b 39.89±2.75a 30.42±1.75b 22.59±2.34c 0.003
粗脂肪EE 70.10±3.73c 72.55±2.73b 75.17±2.65a 71.07±2.60b 74.60±3.51a 0.001
粗灰分Ash 41.13±2.25d 41.12±1.92d 61.41±2.64b 64.57±1.57a 54.50±2.94c 0.006

3 讨论

3.1 饲粮中添加不同比例全株饲料桑对川白獭兔生长性能的影响

近年来,关于桑对畜禽生产性能的影响已有较多报道,但由于桑树品种、栽培措施、加工方式及畜禽种类等的不同导致所得结果有所差异[5-6,8]。本研究结果表明,川白獭兔ADG在各组间无显著差异,但随着饲料桑添加比例的提高呈现先降低后升高的变化趋势,其中以12%和18%添加组下降较明显;同时,各试验组ADG均显著低于对照组,但各试验组间ADG均无显著差异,这可能与全株饲料桑中含有一定量的单宁和植酸等抗营养因子有关。研究表明,当饲粮中单宁含量超过一定量时,饲粮的适口性会降低且会影响动物对营养物质的利用[10]。此外,F/G随着饲料桑添加比例的提高呈现先升高后降低的变化趋势,其中6%和24%组F/G显著低于对照组,而12%和18%添加组F/G与对照组相比无显著差异。因此,从生长性能来看,全株饲料桑在川白獭兔饲粮中的添加比例达到24%时也不会对其产生负面影响,这与陈惠娜等[11]报道的饲粮中桑树茎叶饲料的添加比例在不超过16%时对肉兔生长性能无显著影响的结果不同,原因可能是试验所用桑品种以及试验对象的差异所致。

3.2 饲粮中添加不同比例全株饲料桑对川白獭兔屠宰性能的影响

全净膛率和半净膛率是评定胴体性状的重要指标。本研究发现,24%添加组川白獭兔全净膛率和半净膛率较对照组有所提高,但未达到显著水平;同时,6%和12%添加组全净膛率和半净膛率与对照组相比无显著差异,这说明添加一定比例的全株饲料桑可以一定程度上提高川白獭兔屠宰率,这与侯启瑞等[12]的研究结果类似。器官指数可反映器官功能与代谢强弱,通常情况下免疫器官指数与其免疫性能呈正比[13]。同时,内脏器官重量与能量的利用有关,随着饲粮能量摄入量的增加,试验动物内脏的器官发育也随之加快、增重[14]。本研究结果显示,饲粮中添加全株饲料桑对川白獭兔器官指数、胸腺指数和肝脏指数均无显著影响,且试验期间试验兔未出现不良反应,说明饲料桑对川白獭兔器官生长发育以及免疫器官指数均无负面影响。脾脏是动物免疫能力强弱的器官之一,脾脏指数在一定程度上可反映免疫性能的强弱[15]。本研究中,12%添加组脾脏指数显著高于对照组,同时其心脏指数也高于其余各组,表明饲粮中添加一定比例的饲料桑可以增强川白獭免疫能力,进而维持其机体健康。

3.3 饲粮中添加不同比例全株饲料桑对川白獭兔肉品质的影响

滴水损失和蒸煮损失是评价兔肉嫩度和保水性的重要指标。郭志强等[16]在兔饲粮中添加鲜桑叶(鲜桑叶自由采食+兔体重4%左右精料)后发现,添加鲜桑叶能显著降低肌肉滴水损失,并长时间维持肌肉较高的pH,以此改善兔肉品质。本研究结果显示,饲粮中添加全株饲料桑对川白獭兔肌肉滴水损失率和熟肉率无显著影响,其熟肉率随着饲料桑添加比例的提高呈现先升高后降低的变化趋势,在12%添加组达到最大值。兔肉是富含高生物学价值蛋白质的健康优质肉类,其不饱和脂肪酸含量高,胆固醇含量低。本研究结果表明,饲粮中添加全株饲料桑可显著提高肌肉CP含量,同时显著降低肌肉EE含量,其原因可能与脂肪转变为醛类、醇类、酯类或酮类化等化合物相关[17-18],但其机制还需进一步研究。陈亚迎等[6]和曹满湖等[19]的研究也得到相似结果。

3.4 饲粮中添加不同比例全株饲料桑对川白獭兔血清抗氧化指标的影响

饲料桑富含多种生理活性物质,这使其在畜禽饲料资源中可作为一种天然营养保健剂[20]。抗氧化能力的强弱对动物健康有重要的影响,SOD和MDA等是反映机体抗氧化能力强弱的重要指标。罗阳等[21]研究表明,饲粮中添加发酵桑叶能够促进湘西杂交育肥黄牛的生长,降低血清葡萄糖、总胆固醇及MDA含量从而调节动物的血糖、血脂及抗氧化功能。本研究结果显示,饲粮中添加全株饲料桑对川白獭兔血清SOD活性无显著影响,但12%添加组血清SOD活性高于对照组和其他试验组,这说明饲粮中添加12%全株饲料桑时可一定程度上提高血清SOD活性,从而增强机体清除自由基的能力。T-AOC是所有抗氧化剂的抗氧化能力总和,可一定程度上反映机体清除活性氧/一氧化氮合酶(ROS/NOS)的总能力。本研究中,随着饲料桑添加比例的提高,血清T-AOC持续增强,其原因可能与随着饲料桑添加比例的提高,饲粮中含有的桑叶黄酮等活性物质含量随之提高有关。TBA是肝脏实质性损伤及消化系统疾病的一个较为灵敏的诊断指标,能较为特异地反映肝脏排泄功能,一旦肝细胞有病变或肠-肝循环障碍,均可引起TBA含量升高。何振富等[22]研究表明,随着饲粮综合净能水平的提高,舍饲育肥牦牛血清总胆固醇和TBA含量均呈现出上升的趋势。本研究结果与其相反,本试验结果表明,随着饲料桑添加比例的提高,血清TBA含量呈逐渐下降的趋势,说明饲料桑有利于维持肝脏健康。此外,由于胆固醇分解的重要途径是转变成胆汁酸[23],因此胆汁酸含量的降低可能与桑树中所含活性物质降低了血液中的胆固醇含量有关。MDA是机体脂质过氧化的终产物,其含量越高,说明机体氧化损伤越严重。宋琼莉等[24]研究发现,饲粮中添加10%桑叶粉能显著降低肌肉MDA含量。沈黄冕等[25]研究表明,发酵桑叶能提高高脂血症罗非鱼血清SOD活性,降低血清MDA含量。本研究结果与上述研究结果类似,本试验中,各组间血清MDA含量无显著差异,但随着饲料桑添加比例的提高,其值呈下降趋势而T-AOC呈上升趋势,说明饲料桑是通过降低血清MDA含量来提高机体的抗氧化能力,其原因也可能与桑叶中含有的活性物质有关[26]。

3.5 饲粮中添加不同比例全株饲料桑对川白獭兔养分表观消化率的影响

养分表观消化率能够反映动物对养分的消化吸收与利用情况,是判定饲粮营养价值的重要指标。寇宇斐[27]研究发现,不同添加比例全株桑枝叶对育肥湖羊DM表观消化率无显著影响。刘冬等[28]研究表明,15%发酵桑叶组育肥猪CP和CF表观消化率显著低于对照组。本研究与以上结果不同,本试验结果表明,饲粮中添加一定比例的全株饲料桑可显著提高川白獭兔的DM表观消化率,且DM表观消化率随着饲料桑添加比例的提高呈现先升高后降低的变化趋势,其中以添加12%时DM表观消化率最高,较对照组提高了13.61%,造成该结果的原因可能是饲料桑品种、加工方式及试验对象不同所致。杨阳[29]研究表明,在罗非鱼饲料中添加桑叶粉可一定程度提高CP表观消化率。本研究与其结果类似,本研究结果显示,饲粮中添加全株饲料桑后川白獭兔CP表观消化率呈现先升高后降低的变化趋势,以12%添加组CP表观消化率最高,较对照提高了3.04%。NDF和ADF表观消化率可以反映反刍动物对饲粮纤维物质的利用能力。龚新宇等[30]用青贮桑枝叶饲喂湘中黑牛发现,青贮桑枝叶组NDF和ADF表观消化率较青贮玉米组显著提高,提升幅度达25.86%和40.48%。樊启文等[31]研究表明,以20%发酵饲料桑替代基础饲粮可显著提高NDF表观消化率。王瑶等[32]以蛋白桑青贮替代全株玉米青贮研究其对育肥湖羊生长性能和营养物质消化代谢的影响,结果表明,蛋白桑青贮替代湖羊饲粮中20%~40%的全株玉米青贮能够提高湖羊的养分表观消化率,促进能量代谢。本试验结果与以上研究结果类似,本试验结果表明,饲粮中添加12%全株饲料桑时川白獭兔对饲粮中NDF和ADF的表观消化率均显著高于对照组和其他试验组,且较对照组分别提高了33.94%和35.04%。由此可见,饲粮中添加一定比例的全株饲料桑可促进川白獭兔对纤维的消化吸收。Wang等[33]研究发现,在断奶犊牛的饲粮中添加桑叶黄酮可以提高胃肠道脂肪酶的活性,从而影响EE表观消化率。本试验中,12%添加组EE表观消化率显著高于对照组以及6%和18%添加组,这说明饲粮中添加一定比例的全株饲料桑可以提升川白獭兔的EE表观消化率。从整体趋势看,川白獭兔的养分表观消化率随着饲料桑添加比例的提高呈现先升高后降低的变化趋势,在添加12%时达到最高。因此,饲粮中添加适宜比例全株饲料桑对提高川白獭兔饲粮养分表观消化率具有积极作用。

4 结论

① 饲粮中添加不同比例全株饲料桑对川白獭兔生长性能和屠宰性能无不良影响,且可提高肌肉CP含量,降低肌肉EE含量。
② 饲粮中添加适宜比例全株饲料桑可提高川白獭兔血清T-AOC,降低血清TBA含量,提高脾脏指数和养分表观消化率。
③ 在本试验条件下,全株饲料桑可作为苜蓿草粉替代品饲喂川白獭兔,且饲粮中适宜添加比例为12%。

References

Publishing order | Descend order by publishing year | Descend order by cited within
[1]
傅祥超, 王丽焕, 刘汉中, 等. 仔獭兔饲料中猕猴桃枝条粉适宜添加量的研究[J]. 黑龙江畜牧兽医, 2022(9):124-131,135.

FU X C, WANG L H, LIU H Z, et al. Study on the optimal addition level of kiwifruit branch powder in the diet of young Rex rabbits[J]. Heilongjiang Animal Science and Veterinary Medicine, 2022(9):124-131,135. (in Chinese)

[2]
宋博, 郑昌炳, 仲银召, 等. 低蛋白质饲粮中添加构树全株发酵饲料对育肥猪生长性能、胴体性状和肉品质的影响[J]. 动物营养学报, 2020, 32(10):4841-4851.

DOI

SONG B, ZHENG C B, ZHONG Y Z, et al. Effects of low-protein diet supplemented with fermented Broussonetia papyrifera on growth performance,carcass traits and meat quality of finishing pigs[J]. Chinese Journal of Animal Nutrition, 2020, 32(10):4841-4851. (in Chinese)

[3]
王红林, 左艳春, 周晓康, 等. 高密度草本化栽培对饲料桑全株产量及品质的影响[J]. 草业科学, 2020, 37(5):952-962.

WANG H L, ZUO Y C, ZHOU X K, et al. Influence of high planting density herbal cultivating on yield and quality of whole-plant mulberry (Morus alba)[J]. Pratacultural Science, 2020, 37(5):952-962. (in Chinese)

[4]
杜周和, 左艳春, 严旭, 等. 饲料桑生理活性物质及其饲用价值[J]. 草业学报, 2017, 26(10):227-236.

DOI

DU Z H, ZUO Y C, YAN X, et al. Physiological activation and feed value of mulberry for livestock and poultry[J]. Acta Prataculturae Sinica, 2017, 26(10):227-236. (in Chinese)

[5]
孙海涛, 刘策, 刘公言, 等. 饲粮中不同添加比例饲料桑对育肥兔生长性能、屠宰性能和肌肉品质的影响[J]. 动物营养学报, 2022, 34(4):2586-2595.

DOI

SUN H T, LIU C, LIU G Y, et al. Effects of forage mulberry with differnet addition ratios in diets on growth performance,slaughter performance and meat quality of fattening rabbits[J]. Chinese Journal of Animal Nutrition, 2022, 34(4):2586-2595. (in Chinese)

[6]
陈亚迎, 李娟, 邱时秀, 等. 饲粮中不同比例饲用桑对肉兔屠宰性能、器官指数及肉品质的影响[J]. 中国畜牧杂志, 2020, 56(8):168-171.

CHEN Y Y, LI J, QIU S X, et al. Effects of different proportions of mulberry in feed on slaughter performance,organ index,and meat quality of meat rabbits[J]. Chinese Journal of Animal Science, 2020, 56(8):168-171. (in Chinese)

[7]
石艳华, 杨晓东, 马双马, 等. 桑叶粉替代玉米豆粕饲喂肉兔试验[J]. 黑龙江畜牧兽医, 2007(7):72-73.

SHI Y H, YANG X D, MA S M, et al. Experiment on replacing corn and soybean meal with mulberry leaf powder in feeding meat rabbits[J]. Heilongjiang Animal Science and Veterinary Medicine, 2007(7):72-73. (in Chinese)

[8]
王崇洲, 陈宝剑, 李正欢, 等. 饲用桑茎叶粉对肉兔生产性能、生化指标及肉品质的影响[J]. 饲料研究, 2021, 44(4):51-55.

WANG C Z, CHEN B J, LI Z H, et al. Effect of stem and leaf feed of mulberry on performance,serum biochemical indexes and meat quality of meat rabbits[J]. Feed Research, 2021, 44(4):51-55. (in Chinese)

[9]
中华人民共和国农业农村部. 肉兔营养需要量:NY/T 4049—2021[S]. 北京: 中国农业出版社, 2021.

Ministry of Agriculture and Rural Affairs of the People’s Republic of China. Nutrient requirements of meat rabbit:NY/T 4049—2021[S]. Beijing: China Agricultural Press, 2021. (in Chinese).

[10]
MAKKAR H P S. Effects and fate of tannins in ruminant animals,adaptation to tannins,and strategies to overcome detrimental effects of feeding tannin-rich feeds[J]. Small Ruminant Research, 2003, 49(3):241-256.

[11]
陈惠娜, 郭志强, 郭春华, 等. 桑树茎叶饲料对肉兔生产性能和肉品质的影响[J]. 动物营养学报, 2016, 28(1):109-116.

DOI

CHEN H N, GUO Z Q, GUO C H, et al. Effects of stem and leaf feed of mulberry on performance and meat quality of meat rabbits[J]. Chinese Journal of Animal Nutrition, 2016, 28(1):109-116. (in Chinese)

[12]
侯启瑞, 陶璐璐, 赵卫国, 等. 饲粮中桑叶粉添加量对獭兔生产性能的影响[J]. 蚕业科学, 2016, 42(3):500-506.

HOU Q R, TAO L L, ZHAO W G, et al. Production performance of rex rabbit feeding on diets containing different proportions of mulberry leaf powder[J]. Acta Sericologica Sinica, 2016, 42(3):500-506. (in Chinese)

[13]
任永军, 雷岷, 邝良德. 复合芽孢杆菌制剂对肉兔生产性能、免疫器官指数及肉质的影响[J]. 中国畜牧杂志, 2014, 50(3):73-77.

REN Y J, LEI M, KUANG L D, et al. Effects of the complex bacillus preparation on performance,immune organ index and meat quality of meat rabbits[J]. Chinese Journal of Animal Science, 2014, 50(3):73-77.

[14]
JOHNSON D E, JOHNSON K A, BALDWIN R L. Changes in liver and gastrointestinal tract energy demands in response to physiological workload in ruminants[J]. Journal of Nutrition, 1990, 120(6):649-655.

PMID

[15]
赵艳兵, 任有蛇, 张春香, 等. 日粮中添加荞麦秸秆对绵羊屠宰性能、器官指数、肉品质及血液生化指标的影响[J]. 山西农业大学学报(自然科学版), 2017, 37(12):872-878.

ZHAO Y B, REN Y S, ZHANG C X, et al. Effect of dietary buckwheat straw level on slaughter performance,organ indexes,meat quality and blood biochemical index in sheep[J]. Journal of Shanxi Agricultural University (Natural Science Edition), 2017, 37(12):872-878. (in Chinese)

[16]
郭志强, 梅秀丽, 雷岷, 等. 饲粮补充鲜桑叶对肉兔生产性能和肉品质的影响[J]. 西南农业学报, 2017, 30(1):215-221.

GUO Z Q, MEI X L, LEI M, et al. Fresh mulberry leaves-supplemented diets on performance and meat quality of rabbit[J]. Southwest China Journal of Agricultural Sciences, 2017, 30(1):215-221. (in Chinese)

[17]
DEL PULGAR J S, ROLDAN M, RUIZ-CARRASCAL J. Volatile compounds profile of sous-vide cooked pork cheeks as affected by cooking conditions (vacuum packaging,temperature and time)[J]. Molecules, 2013, 18(10):12538-12547.

[18]
何亮宏, 陈国顺, 权群学, 等. 桑叶粉对生长肥育猪生长性能、屠宰性能、肉质及风味的影响[J]. 中国畜牧杂志, 2018, 54(8):68-74.

HE L H, CHEN G S, QUAN Q X, et al. Effect of adding mulberry leaf powder on the production performance,slaughter performance,meat quality and flavor of pigs[J]. Chinese Journal of Animal Science, 2018, 54(8):68-74. (in Chinese)

[19]
曹满湖, 金睿, 温建崇, 等. 桑叶提取物对AA肉鸡肉品质的影响及其作用机理[J]. 湖南农业大学学报(自然科学版), 2023, 49(3):344-351.

CAO M H, JIN R, WEN J C, et al. Effect of mulberry leaf extract on the meat quality of AA broilers and its mechanism[J]. Journal of Hunan Agricultural University (Natural Sciences), 2023, 49(3):344-351. (in Chinese)

[20]
刘小明, 曹玉华. 饲料中添加桑叶粉对蛋鸡产蛋性能和鸡蛋品质的影响[J]. 湖南农业科学, 2011(11):132-133,136.

LIU X M, CAO Y H. Effects of adding mulberry-leaf powder to feed on laying performance of layers and egg quality[J]. Hunan Agricultural Sciences, 2011(11):132-133,136. (in Chinese)

[21]
罗阳, 李昊帮, 肖建中, 等. 发酵桑叶对湘西黄牛×利木赞杂交F1代育肥牛血清生化、抗氧化及免疫指标的影响[J]. 动物营养学报, 2020, 32(10):4914-4921.

DOI

LUO Y, LI H B, XIAO J Z, et al. Effects of fermented mulberry leaves on serum biochemical,antioxidant and immune indexes of Xiangxi yellow cattle×Limousin hybrid F1 fattening bulls[J]. Chinese Journal of Animal Nutrition, 2020, 32(10):4914-4921. (in Chinese)

[22]
何振富, 谢建鹏, 陈平, 等. 不同蛋白质、能量水平饲粮对舍饲育肥牦牛生长性能、养分表观消化率及血清生化指标的影响[J]. 动物营养学报, 2024, 36(3):1698-1712.

DOI

HE Z F, XIE J P, CHEN P, et al. Effects of different protein and energy levels of diets on growth performance,nutrient apparent digestibility and serum biochemical indexes of fattening yaks in shelter feeding[J]. Chinese Journal of Animal Nutrition, 2024, 36(3):1698-1712. (in Chinese)

[23]
李亚婷, 李强, 李娜, 等. 牛油果油对肥胖小鼠体重、血清生化指标和肝脏中胆固醇代谢相关基因表达的影响[J]. 动物营养学报, 2023, 35(11):7389-7400.

DOI

LI Y T, LI Q, LI N, et al. Effects of avocado oil on body weight,serum biochemical indexes and expression of genes related to cholesterol metabolism in liver of obese mice[J]. Chinese Journal of Animal Nutrition, 2023, 35(11):7389-7400. (in Chinese)

[24]
宋琼莉, 韦启鹏, 邹志恒, 等. 桑叶粉对育肥猪生长性能、肉品质和血清生化指标的影响[J]. 动物营养学报, 2016, 28(2):541-547.

DOI

SONG Q L, WEI Q P, ZOU Z H, et al. Effects of mulberry leaf powder on growth performance, meat quality and serum biochemical indexes in finishing pigs[J]. Chinese Journal of Animal Nutrition, 2016, 28(2):541-547. (in Chinese)

[25]
沈黄冕, 彭祥和, 林仕梅, 等. 发酵桑叶对高脂血症罗非鱼血脂、血糖水平的调节作用[J]. 动物营养学报, 2016, 28(4):1250-1256.

DOI

SHEN H M, PENG X H, LIN S M, et al. Regulation of fermented mulberry leaves on serum lipid and blood glucose levels of hyperlipidemia tilapia (Oreochromis niloticus)[J]. Chinese Journal of Animal Nutrition, 2016, 28(4):1250-1256. (in Chinese)

[26]
TONG L T, ZHONG K, LIU L Y, et al. Effects of dietary hull-less barley β-glucan on the cholesterol metabolism of hypercholesterolemic hamsters[J]. Food Chemistry, 2015,169:344-349.

[27]
寇宇斐. 饲料桑的营养动态及其对育肥湖羊生产性能的影响[D]. 硕士学位论文. 兰州: 兰州大学, 2021.

KOU Y F. Nutrition dynamics of mulberry and its effect on production performance of fattening Hu sheep[D]. Master’s Thesis. Lanzhou: Lanzhou University, 2021. (in Chinese)

[28]
刘冬, 丁兆忠, 胡蕾, 等. 发酵桑叶替代基础日粮对育肥猪生长性能、血清生化指标、养分表观消化率及肉品质的影响[J]. 饲料研究, 2023, 46(15):17-22.

LIU D, DING Z Z, HU L, et al. Effect of fermented mulberry leaves replacing basic diet on growth performance,serum biochemical indexes,nutrient apparent digestibility,and meat quality of finishing pigs[J]. Feed Research, 2023, 46(15):17-22. (in Chinese)

[29]
杨阳. 桑叶对罗非鱼生长、代谢及品质的影响[D]. 硕士学位论文. 重庆: 西南大学, 2015.

YANG Y. Effects of mulberry leaves on growth,metabolism and quality of tilapia (Oreochromis niloticus)[D]. Master’s Thesis. Chongqing: Southwest University, 2015. (in Chinese)

[30]
龚新宇, 陈郸曲, 周宇桥, 等. 青贮桑枝叶对湘中黑牛生长性能、养分表观消化率、瘤胃发酵参数和血清生化指标的影响[J]. 中国畜牧杂志, 2024, 60(4):241-246.

GONG X Y, CHEN D Q, ZHOU Y Q, et al. The effects of silage mulberry branches and leaves on the growth performance,nutrient apparent digestibility,rumen fermentation parameters,and serum biochemical indicators of Xiangzhong black cattle[J]. Chinese Journal of Animal Science, 2024, 60(4):241-246. (in Chinese)

[31]
樊启文, 郭万正, 赵娜, 等. 不同比例发酵饲料桑替代基础饲粮对肉牛生长性能、养分表观消化率、血液生理生化指标、血清抗氧化指标的影响[J]. 动物营养学报, 2023, 35(11):7235-7246.

DOI

FAN Q W, GUO W Z, ZHAO N, et al. Effects of different proportions of basal diet replaced by fermented feed mulberry on growth performance,nutrient apparent digestibility,blood physiological and biochemical indexes and serum antioxidant indexes of beef cattle[J]. Chinese Journal of Animal Nutrition, 2023, 35(11):7235-7246. (in Chinese)

[32]
王瑶, 张雨, 韩佳佳, 等. 蛋白桑青贮替代全株玉米青贮对育肥湖羊生长性能和营养物质消化代谢的影响[J]. 动物营养学报, 2023, 35(6):3822-3831.

DOI

WANG Y, ZHANG Y, HAN J J, et al. Effects of replacing whole corn silage with Morus alba silage on growth performance and nutrient digestion and metabolism of fattening Hu sheep[J]. Chinese Journal of Animal Nutrition, 2023, 35(6):3822-3831. (in Chinese)

DOI

[33]
WANG B, YANG C T, DIAO Q Y, et al. The influence of mulberry leaf flavonoids and Candida tropicalis on antioxidant function and gastrointestinal development of preweaning calves challenged with Escherichia coli O141:K99[J]. Journal of Dairy Science, 2018, 101(7):6098-6108.

Options
Outlines

/

〈 〉

京ICP备17050989号-2
Copyright © Chinese Journal of Animal Nutrition, All Rights Reserved.
Tel: 010－62817823　E-mail: cjan@vip.163.com
Powered by Beijing Magtech Co., Ltd.