不同限饲方法对爱拔益加肉鸡生长性能、屠宰性能及骨骼性状的影响

Effects of Different Feed Restriction Methods on Growth Performance,Slaughter Performance and Skeletal Traits of Arbor Acres Chickens

本试验旨在研究不同限饲方法对爱拔益加(AA)肉鸡生长性能、屠宰性能及骨骼性状的影响。试验选用80只7日龄的AA肉鸡,随机分成4组:对照组、料量限饲组、能量限饲组和蛋白质限饲组,每组20只鸡。限饲14d(21日龄)、补偿生长21d(42日龄)后每组分别屠宰8只,取其胸肌、腿肌、腹脂、心脏、肝脏、脾脏、胸腺、法氏囊、骨骼等组织并称重,以及测量骨骼的长度和直径。结果表明:1)限饲后,3个限饲组肉鸡的平均日增重显著低于对照组(P<0.05)。补偿生长后,各组肉鸡的平均日采食量、平均日增重和料重比均差异不显著(P>0.05),但料量限饲组末重显著低于对照组(P<0.05)。2)限饲后,料量限饲组肉鸡的全净膛率、半净膛率、胸肌率、腿肌率和腹脂率显著低于对照组(P<0.05),料量限饲组、能量限饲组肉鸡的腹脂率显著低于蛋白质限饲组和对照组(P<0.05)。补偿生长后,各组肉鸡的胸肌率和腿肌率均无显著差异(P>0.05),但料量限饲组肉鸡的腹脂率显著高于对照组(P<0.05)。3)限饲后,蛋白质限饲组肉鸡的肝脏指数显著高于其他3组(P<0.05),料量限饲组肉鸡的胰脏指数显著高于其他3组(P<0.05);对照组脾脏指数显著高于其他3组(P<0.05)。补偿生长后,各组肉鸡的心脏指数、肝脏指数、胰脏指数、脾脏指数、胸腺指数和法氏囊指数均无显著差异(P>0.05)。4)限饲后,料量限饲组肉鸡的胫骨重、胫骨长、胫骨直径、股骨重和股骨长显著低于其他3组(P<0.05),料量限饲组、能量限饲组肉鸡的股骨直径显著低于对照组和蛋白质限饲组(P<0.05)。补偿生长后,各组肉鸡的胫骨重、胫骨长、胫骨直径、股骨重、股骨长和股骨直径均无显著差异(P>0.05)。由此可见,3种限饲方法均降低了AA肉鸡的平均日增重和部分骨骼性状指标,其中料量限饲法对肉鸡平均日增重和骨骼性状影响最大。经过21d的补偿生长后,3种个限饲组均表现出补偿生长效应,骨骼性状无显著变化,但料量限饲法会降低肉鸡全期的平均日增重和末重,建议生产中慎用料量限饲法。

This experiment was conducted to study the effects of different feed restriction methods on growth performance, slaughter performance and skeletal traits of Arbor Acres （AA） chickens. Eighty 7-day-old AA chickens were fed in our experiment. The chickens were randomly assigned to 4 groups：control group, feed intake restriction group, energy restriction group and protein restriction group, with 20 replicates per group. Eight chickens of each group were selected to slaughter after feed restriction for 14 days （21-day-old） and compensatory growth （after the feed restriction） for 21 days （42-day-old）, respectively. The chest muscle weight, leg muscle weight, abdominal fat weight, heart weight, liver weight, spleen weight, thymus weight, bursal weight, leg bone weight, and the length and diameter of the tibia and femur were measured, respectively. The results showed as follows：1） after feed restriction, the average daily gain of chickens of three restriction groups was significantly lower than that of control group （P〈0.05）. After compensatory growth, the average daily feed intake, average daily gain and feed to gain ratio had no significant difference among all group （P〉0.05）, however, the final weight of feed intake restriction group was significantly lower than that of control group （P〈0.05）. 2） After feed restriction, the eviscerated ratio, semi-eviscerated, breast muscle ratio, leg muscle ratio and abdominal fat ratio of chickens of feed intake restriction group were significantly lower than those of control group （P〈0.05）, the abdominal fat ratio of chickens of feed intake restriction group and energy restriction group was significantly lower than that of protein restriction group and control group （P〈0.05）. After compensatory growth, there were no significant differences on breast muscle ratio and leg muscle ratio of chickens among all group （P〉0.05）, however, the ratio of abdominal fat of feed restriction group was significantly higher than that in the control group （P〈0.05）. 3） After feed restriction, the liver index of chickens of protein restriction group was significantly higher than that of other three groups （P〈0.05）, the pancreas index of chickens of feed intake restriction group was significantly higher than that of other three groups （P〈0.05）, the spleen index of chickens of control group was significantly higher than that of other three groups （P〈0.05）. After compensatory growth, there were no significant differences on heart index, liver index, pancreas index, spleen index, thymus index and bursal of Fabricii index of chickens among all group （P〉0.05）. 4） After feed restriction, the tibia weight, tibia length, tibia diameter, femur weight and femur length of chickens of feed intake restriction group were significantly lower than those of other three groups （P〈0.05）, the femur diameter of chickens of feed intake restriction group and energy restriction group was significantly lower than that of control group and protein restriction group （P〈0.05）. After compensatory growth, there were no significant differences on tibia weight, tibia length, tibia diameter, femur weight, femur length and femur diameter of chickens among all group （P〉0.05）. In conclusion, the average daily gain and partial skeletal trait indexes on AA chicken are reduced by three feed restriction methods, and the feed intake restriction group has a greatest influence on average daily gain and skeletal traits of chickens. After 21 days of compensatory growth, the three restriction groups exhibit compensatory growth effects, there are no significant differences on skeletal traits among three restriction groups and control group. However, the average daily gain and final weight are decreased by feed intake restriction method, we suggest that the feed intake restriction method should be used prudently in the actual production.