氨基酸是一种含氨基有有机酸,是组成蛋白质的基本单位。构成蛋白质的氨基酸有二十多种,按其对猪、鸡的营养需要来讲,通过常又分为必需氨基酸和非必需氨基酸两类。在猪、鸡体内不能合成,或虽能合成但合成的速度及数量不能满足其正常生长需要,因而必须由外界供给的氨基酸,叫必需氨基酸。迄今为止已被饲养业所普遍使用的必需氨基酸有蛋氨酸和赖氨酸,近年来,由于生产技术的 Amino acids are amino acids that contain organic acids and are the basic unit of protein composition. There are more than twenty kinds of amino acids that constitute proteins, which are often divided into essential amino acids and non-essential amino acids according to their nutritional needs for pigs and chickens. In pigs, chickens can not be synthesized, or synthesis but the speed and quantity of synthesis can not meet its normal growth needs, which must be supplied by the outside world of amino acids, called essential amino acids. The essential amino acids that have been used so far by the husbandry industry are methionine and lysine. In recent years, due to production technology,