生长猪氨基酸利用的数量观点:理论与实践

本文综述了影响生长猪氨基酸利用的主要因素,探讨了养猪生产中有关氨基酸营养问题。结果表明:通过测定体沉积蛋白质(PD)中氨基酸的沉积、生理氨基酸损失(主要是皮肤和毛发、肠道内源氨基酸损失)与不可避免的氨基酸的分解代谢来估测氨基酸的需要量,估测氨基酸需要量的数据必须建立在蛋白质沉积、活体量、饲喂水平、饲料原料组成和饲料原料的可利用氨基酸含量上。既然PD是氨基酸需要量的决定因素,在建立日粮最佳氨基酸水平时,必须认真考虑活体重或动物间的差异对PD的影响。因此,饲料组成与机体蛋白质中氨基酸组成的变化对用于蛋白质沉积需要的可利用氨基酸利用的影响必须进行更精确的定量。

QUANTITATIVE ASPECTS OF AMINO ACID UTILIZATION FOR GROWTH IN THE PIG:THEORY AND PRACTICE

In this article the main factors that are known to influence amino acid utilization in growing pigs are reviewed and their relevance to practical pig nutrition and pork production is discussed.It is concluded that the growth response of pigs to available amino acid intake could be estimated with a reasonable accuracy from amino acid'requirements'for amino acid retention with whole body protein deposition (PD),physical amino acid losses-mainly skin and hair,and endogenous gut amino acid losses-and inevitable amino acid catabolism.When estimating amino acid requirements information is needed on PD,live body weight,feeding level,feed ingredient composition and the available amino acid content in feed ingredients.Since PD is the main determinant of amino acid requirements,the influences of live body weight or between animal variation on PD should be considered carefully when establishing optimum diet amino acid levels.The effects of feed composition and changes in the amino acid composition of whole body protein on the utilization of available amino acid intake for PD need to be quantified more accurately.