家禽支链氨基酸营养需要研究进展

Advances in Research on the Nutritional Requirements of Branched-Chain Amino Acids in Poultry

支链氨基酸(branched-chain amino acids,BCAA)在家禽生长、生产性能、免疫功能和肠道健康等方面发挥着重要作用,涉及器官发育、免疫反应、肌肉蛋白周转和基因调控等关键过程。然而,单一BCAA的过量、缺乏或比例失衡均会影响家禽蛋白质合成和肠道健康,因此保持BCAA比例的平衡对于家禽的生产性能至关重要。尽管NRC(1994)提供了肉鸡、蛋鸡和种鸡的BCAA推荐量,但不同日粮蛋白质水平以及不同品种和生长阶段的家禽对BCAA的需求存在差异。同时,鉴于抗生素生长促进剂的禁用及养殖端所面临的多种疾病的挑战,也需要重新评估家禽对BCAA的推荐摄取水平。另外,BCAA在维持肠道完整性、调控肠道微生物组成以及提高机体蛋白周转效率的作用机理研究仍有待进一步探究。本综述在阐述BCAA在家禽中的营养生理作用以及其对生产和健康的基础上,推荐了不同饲养条件下不同肉鸡品种(肉鸡、蛋鸡和种鸡)BCAA需要量,以期为家禽低蛋白日粮BCAA推荐量提供理论参考。

Branched-chain amino acids(BCAA)play important roles in poultry growth,production performance,immune function and intestinal health.They are involved in key processes such as organ development,immune response,muscle protein turnover and gene regulation.However,an excess,deficiency or imbalance of a single BCAA can affect poultry protein synthesis and intestinal health.Therefore,maintaining a balanced ratio of BCAA is critical for poultry performance.Although the NRC(1994)provides recommended amounts of BCAA for broilers,laying hens,and breeders,there are variations in BCAA requirements among poultry breeds,dietary protein levels,and growth stages.Meanwhile,the ban on antibiotic growth promoters and the challenges of multiple diseases in poultry farming necessitate a re-evaluation of the recommended levels of BCAA intake.Additionally,more research is needed to explore the mechanisms of action of BCAA in maintaining intestinal integrity and regulating gut microbial composition and enhancing protein turnover efficiency in the body.This review aims to describe the nutritional and physiological roles of BCAA in poultry,as well as their effects on production and health.And also provides BCAA requirements for different broiler breeds(broilers,laying hens and breeders)under various feeding conditions.These recommendations aim to provide theoretical references for the recommended levels of BCAA in low-protein diets for poultry.