铬对产蛋鸡生产性能的影响及其在体内的分布

在基础日粮中分别添加不同剂量铬饲养４个月，观察产蛋率、蛋重、蛋壳质量、哈夫单位、蛋形指数、采食量、体重等变化情况；每隔１个月采血１次，对血浆、蛋黄、羽毛、肝脏、脾脏、胸肌中铬元素含量进行了测定。实验结果表明：３种日粮铬水平对采食量、壳厚、蛋壳密度、蛋形指数均无显影响；添加５ｍｇ／ｋｇ Ｃｒ有利于早期蛋增重，利于高哈夫单位的维持，利于产蛋率的提高及产蛋高峰期（〉９０％）的持久。过高过低Ｃｒ日粮均不

Effects of Dietary Chromium on the Productivity of Laying Hens and the Distribution of Chromium

The experiment dealt with effects of dietary Chromium on the productivity of laying hens and the distribution of Chromium. The results showed that there were no significant differences among the three groups fed with different dietary Chromium levels in feed consumption, shell quality. Chromium at 5.09 mg/kg could meet the basic needs of physiologieal functions, but had difficulty to exert the best productive potential of the laying hens, while rations containing 10.09 mg/kg Chromium suited the hens well which enhanced egg weight, egg productive ratio and egg white quality significantly and prolonged the period of laying peak (>90%). Better effects were not found in diet of 55.09 mg/kg Chromium. Chromium is mainly stored in muscle, liver and spleen.