轻度热应激下蛋鸡产蛋高峰期主要营养素适宜摄入量的研究

OPTIMUM DAILY NUTRIENT INTAKES FOR LAYERS AT PEAK PRODUCTION UNDER HIGHER ENVIRONMENTAL TEMPERATURE

用360只24周龄伊莎褐商品蛋鸡,进行L_9(3~4)正交试验,随机分组设计,探讨在轻度热应激(29.56±1.07℃)下,饲粮代谢能(11.09、11.72、12.34MJ/kg)、粗蛋白质(16％、18％、20％)、钙(3.2％、3.7％、4.2％)和有效磷(0.34％、0.42％、0.50％)对蛋鸡生产性能的影响。结果表明,提高饲粮代谢能和有效磷可有效地缓解热应激导致的生产性能的下降,而提高饲粮蛋白质和钙则不能缓解热应激对生产性能的影响。通过试验,提出了保持27～32用龄蛋鸡产蛋率达90％以上的主要养分适宜摄入量。

L9(34) orthogonal experiment with randomized block design was used to study the effect of dietary crude protein (CP, 16% , 18% , 20%), metabohzable energy (ME, 11. 09, 11, 72, 12.34MJ / kg),calcium(Ca,3.2%,3.7% ,4.2%),available phosphrus (AP,0.34%,0.42% , 0. 50%) levels on laying performance at hipher environmental temperature (29. 56±1. 07℃). The results showed that elevated environmental temperature decreased feed intake and laying performance(P < 0. 01). Under higher environmental temperature, the increase of dietary ME and AP could improve signifcantly laying performance , but the increase of CP and Ca couldnot. The optimum daily intake of mam nutrients were established in this experiment for layers of 27~32 weeks old to reach 90% laying rate.