Nutritional Interrelationship between Sulfate and Amino Acids in Chicks

在高含硫氨基酸和硫的商业配方饲料中，饲喂硫酸盐导致雏鸡增重降低。另一方面，在饲粮中这些成分含量较低的雏鸡中，通过饲喂硫酸盐提高了体重增重。研究了在大豆蛋白（唯一蛋白质来源）中添加或不添加0.44% dl -蛋氨酸的半纯化饲粮中，硫酸盐与营养中氨基酸的相互关系。饲粮中添加硫酸钠导致血浆尿酸水平升高，而尿液尿酸含量未受影响。添加硫酸盐后，体内含硫氨基酸的水平不变。添加硫酸盐可提高肝脏谷氨酸-草酰乙酸转氨酶活性。随着血浆游离丝氨酸浓度的增加，肾脏丝氨酸脱水酶活性降低。低水平蛋氨酸饲粮中添加硫酸盐可显著提高肝脏中谷胱甘肽含量，肝脏中蛋氨酸活化酶活性。结果表明，饲粮中添加的硫酸盐被用来合成含硫化合物，如牛磺酸，而不是含硫氨基酸。

Feeding sulfate resulted in decreased body weight gain of chicks fed commercial formula feed containing a high content of sulfur amino acid and sulfur. On the other hand, in chicks fed a diet containing a low content of these components the body weight gain was improved by feeding sulfate.The interrelationship between sulfate and amino acids in nutrition was studied in chicks fed semi-purified diets containing soybean protein (the sole protein source) supplemented with or without 0.44% DL-methionine. The addition of sodium sulfate to the diet resulted in increased level of uric acid of blood plasma, while the content of uric acid of urine was not affected. The level of sulfur amino acids within the body was unchanged by addition of sulfate. The activity of glutamate-oxaloacetate transaminase in liver was increased by sulfate supplemented. The activity of serine dehydratase in kidney was decreased when the concentration of free serine in blood plasma was increased by addition of sulfate. The content of glutathione in liver tended to increase, and the activity of methionine activating enzyme in liver was increased markedly by addition of sulfate in chicks fed a diet containing a low level of methionine.It was shown that sulfate supplemented to the diet was utilized for synthesis of sulfur-containing compounds such as taurine, not of sulfur amino acids.