氨是氨基酸代谢的产物。
型半胱氨酸是一种含硫氨基酸，是蛋氨酸代谢的中间产物。
Homocysteine (Hcy) is a kind of sulphur-containing amino acid, the intermediate product of the methionine metabolism.
作者着重阐述支链氨基酸对泌乳的特殊作用，泌乳母猪对支链氨基酸的需要量，以及支链氨基酸及其代谢产物对蛋白质合成和降解的影响。
This paper discusses the special functions of BCAA for lactating animals, the requirement of BCAA by lactating sows, and the effects of BCAA and their metabolites on protein synthesis and degradation.
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