饲粮ME和DLys水平对21～42日龄肉仔鸡营养物质代谢率的影响

Effects of ME and DLys Levels on Utilization of Nutrients for Broilers at the Age of 21 to 42 Days

为研究氨基酸平衡饲粮的代谢能(ME)、可消化赖氨酸(DLys)水平及其互作效应对21~42日龄肉仔鸡营养物质代谢率的影响,试验采用两因素析因试验设计,将ME设为12.55MJ·kg-1和13.18MJ·kg-1两个水平,DLys设为0.8%、0.95%、1.1%三个水平,依据理想氨基酸平衡模式配制6种试验饲粮。选取360只平均体重718.6g的21日龄AA+肉仔鸡,随机分为6组,每组6个重复,试验期为21d,在试验期的最后3d采用全收粪法进行代谢试验,测定干物质(DM)、能量、氮(N)、磷(P)及氨基酸(AA)的代谢率。结果表明:ME与DLys的互作效应对DM、能量和P代谢率无显著影响(p】0.05),但对N代谢率有极显著影响(p【0.01)。低ME低DLys组具有最高的DM、能量及P代谢率,高ME低DLys组的N代谢率最高。不同水平的ME与DLys除对组氨酸(His)、丙氨酸(Ala)代谢率无显著影响外(p】0.05),对其他AA和总AA的代谢率均有显著(p【0.05)或极显著(p【0.01)影响。综合DM、总能、N及P代谢率指标,本试验条件下,21~42日龄肉仔鸡最适宜营养代谢的ME/DLys为1.55或1.65MJ·g-1,而无论高、低ME,DLys水平达到1.1%时AA的代谢率最高。

In order to study metabolizable energy(ME)and digestible lysine(DLys)levels and their interactive effects on utilization of nutrients for broiler chickens at 21 to 42 days of age, the experiment was carried out using two factor factorial design. The dietary treatments were formulated two levels of ME and three levels of DLys as 12.55MJ·kg-1and 13.18MJ·kg-1and0.8%, 0.95%, 1.1%, respectively, and six experimental diets based on the ideal amino acid balanced model were formulated. A total of 360 21d-old Arbor Acres broiler chickens average weighting 718.6g were selected and randomly divided into 6treatments, each of which contained 6 replicates, and metabolizable trial based on total feces collection method was carried out during the last three days of 21 days feeding periods. Dry matter(DM),energy, nitrogen(N), phosphorus(P)and amino acids(AA)utilization were measured. Results showed that there was no significant(p>0.05) interaction of dietary ME and DLys effects on DM, energy and P utilization, however their effects on N utilization was significant(p<0.01). The group of low energy and low DLys diet has the hightest utilization of DM, energy and P, and the highest utilization of N was the group of high ME and low DLys diet. There was no significant(p>0.05)effect on histidine and phenylalanine utilization by different levels of ME and DLys,but was significant(p <0.05)effect on other AA and total AA utilization. Comperhensive results of the utilization of DM, gross energy, N and P indicated that the broilers got the optimum ME to DLys ratio(ME/DLys) of nutrient utilization was 1.55 or 1.65 MJ·g-1,However, no matter high ME or low ME,AA utilization was the highest at the level of DLys contained 1.1%.