不同鸡品种和不同日龄肉鸡的饲粮能量分配途径和效率比较研究

Comparative Study on Approach and Efficiency of Energy Distribution in Different Breeds and Different Ages of Broilers

本研究使用新型12室并联禽用开放回流式呼吸测热装置测定不同鸡品种及不同日龄肉鸡的饲粮能量在其体内的转化途径,以期探究不同鸡品种和不同日龄肉鸡的饲粮能量效率。试验选用45周龄海兰褐蛋鸡、25日龄爱拔益加(AA)肉鸡、14日龄AA肉鸡各20只,采用完全随机试验设计,每个品种设置8个重复,每个重复2只鸡。试验鸡饲喂满足各自营养需要的试验饲粮。试验分2期完成,每期6 d,每期从每种试验鸡中随机选择8只,称重后每2只放入1个呼吸测热装置的代谢室内,每4个代谢室对应1种鸡。代谢室内测定气体交换6 d,其中适应期3 d,呼吸测热3 d,呼吸测热期间记录采食量和全收粪法收粪。结果表明:饲粮能量在家禽体内逐级递减流动,与食入总能相比,产蛋高峰海兰褐蛋鸡、25日龄AA肉鸡、14日龄AA肉鸡饲粮能量分配效率分别为表观代谢能(AME)77.78%、76.78%、76.89%,净能(NE)59.50%、59.67%、49.62%,沉积能(RE)23.87%、35.21%、27.96%。综上所述,不同试验鸡品种因其自身对饲粮能量代谢差异,导致饲粮能量分配效率不同,相同试验鸡品种在不同日龄阶段,因其自身营养物质需求差异,导致饲粮能量分配效率和方向不同。

In this experiment,the open-circuit respiratory instrument with twelve chambers in parallel for poultry was used to determine the dietary energy conversion pathway of different chicken breeds in vivo,in order to explore the dietary energy utilization efficiency of different chicken breeds and chicken with different ages.Twenty 45-week-old Hy-Line Brown laying hens,25-day-old Arbor Acres(AA)broilers and 14-day-old AA broilers were selected respectively in the experiment.Each breed was randomly divided into 8 replicates with 2chickens per replicate.The experimental chickens were fed diets to meet their nutritional needs.The experiment was divided into 2 periods and each period lasted for 6 days,eight chickens of each species were randomly selected in each period.After weighing,every 2 chickens were put into the respiratory calorimeter chamber,and every 4 chambers were corresponding to one kind of chickens.Gas exchange was measured in the metabolic chamber for 6 days,including 3 days of adaptation period and 3 days of respiratory calorimetry.During respiratory calorimetry,feed intake was recorded and feces were collected by total feces collection method.The results showed as follows:the dietary energy in poultry decreases gradually.Compared with gross energy intake,the dietary energy distribution efficiency of Hy-Line Brown laying hens,25-day-old AA broilers and 14-dayold AA broilers was AME 77.78%,76.78%and 76.89%,respectively;NE 59.50%,59.67%and 49.62%,respectively;RE 23.87%,35.21%and 27.96%.In conclusion,different breeds of chickens have different dietary energy distribution efficiencies due to their own differences in dietary energy metabolism.The efficiency and direction of dietary energy distribution are different for chickens of the same breed at different age stages due to their different demands for nutrients.