标准回肠可消化缬氨酸水平对生长猪生长性能、血浆氨基酸和尿素氮含量的影响

Effects of Standardized Ileal Digestible Valine Level on Growth Performance,Plasma Amino Acids and Urea Nitrogen Contents of Growing Pigs

本试验旨在探讨饲粮中不同标准回肠可消化缬氨酸水平对生长猪生长性能、血浆氨基酸和尿素氮含量的影响。试验选用420头始重为（24．31±1．74）kg的杜×长×大三元生长猪，按体重相近、遗传基础相似的原则，随机分为5个处理，每个处理6个重复，每个重复14头猪。试验饲粮除缬氨酸水平外，其余营养水平均参照NRC（2012）推荐标准设计，试验饲粮标准回肠可消化缬氨酸水平分别为0．59％、0．64％、0．69％、0．74％和0．79％。结果表明：饲粮标准回肠可消化缬氨酸水平为0．69％、0．74％和0．79％处理的平均日增重和料重比差异不显著（ P＞0．05），但较标准回肠可消化缬氨酸水平为0．59％的处理得到显著改善（ P＜0．01），同时随着饲粮标准回肠可消化缬氨酸水平增加均呈线性和二次趋势（ P＜0．01）。采用折线模型和二次回归趋势，综合平均日增重和料重比的分析，当饲粮中标准回肠可消化赖氨酸水平为0．98％，得到20～50 kg生长猪饲粮标准回肠可消化缬氨酸需要量范围为0．65％～0．73％，最佳需要量为0．68％。

This experiment was conducted to investigate the effects of dietary standardized ileal digestible （ SID）valine（ Val）level on growth performance,plasma amino acids and urea nitrogen contents of growing pigs. This experiment was conducted to choose 420 barrows（ Duroc×Landrace×Yorkshire）which were allotted to 5 treatments with 6 replicates per treatment and 14 barrows per replicate. Except dietary Val level,the nutri-ent levels of experimental diets were referred to recommended the nutrient requirements of swine in NRC（2012）, therefore dietary SID Val levels were 0.59%,0.64%,0.69%,0.74% and 0.79%,respectively. The results showed as follows：the average daily gain and feed to gain ratio of treatments with the dietary SID Val level at 0.69%,0.74% and 0.79% were no significantly different（ P〉0.05）,but were significantly improved when compared with the treatment with the dietary SID Val level at 0.59%（ P〈0.01）. With the dietary SID Val level increased,the average daily gain and feed to gain ratio had linear and quadratic trend（P〈0.01）. With broken-line model and quadratic regression trend of the data from average daily gain and feed to gain rati-o,this trial showed that the dietary SID Val requirement is 0.65% to 0.73% when the dietary SID Lys level is 0.98%,and the optimum SID Val level is 0.68% for 20 to 50 kg growing pigs.