Nutritional Interrelationship between Sulfate and Amino Acids in Chicks

饲喂含硫、氨基酸和硫含量较高的商品配方饲料的雏鸡，饲喂硫酸盐可降低其增重。另一方面，在饲喂这些成分含量较低的日粮中，添加或不添加0.44%DL-蛋氨酸的半纯日粮中，添加或不添加0.44%DL-蛋氨酸的半纯日粮中，硫酸盐与营养中氨基酸的相互关系得到了改善。日粮中添加硫酸钠后，血浆尿酸水平升高，而尿尿酸含量无明显变化。添加硫酸盐不影响体内含硫氨基酸水平。添加硫酸盐可提高肝脏谷草转氨酶活性。添加硫酸盐使血浆中游离丝氨酸浓度升高，肾脏丝氨酸脱水酶活力降低。在饲喂低水平蛋氨酸的日粮中添加硫酸盐后，肝脏中谷胱甘肽的含量有增加的趋势，肝脏中蛋氨酸活化酶的活性显著提高。这表明，在日粮中添加硫酸盐是用于合成牛磺酸等含硫化合物，而不是合成含硫氨基酸。

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.