饲料营养水平对乌鸡肉用性能的影响

将２００只雄性雏乌鸡随机分为４组，第一组全程使用中等营养水平饲料，第二组全程使用较高营养水平饲料，第三组于６周龄前用中等营养、以后用较高营养料，第四组与第三组相反，共饲养１３周。结果第二组增重最高，第三组次之，第一组最低；饲料转化率的测定结果与体增重情况相似。各组的死亡率无显著差异。试验期末商品鸡的整齐度第三组最好，第二组次之，第四组最差。全净膛率、胸肌率和腿肌率无明显星差异。综合评价以第三组的营养水平调整方式效果最佳。

Effect of feed nutrition levels on the meat performance of black boned chickens

young male black boned chickens were randomly assigned to one of four groups with group l given medium nutrition level feed de novo, group 2 high nutrition level feed de novo, group 3 medium nutrition level feed before 6 weeks of age and then high nutrition level feed, and group 4 high nutrition level feed before 6 weeks of age and then medium nutrition level feed in a feeding period of 13 weeks. It was shown that group 2 was highest in weight gain,followed by group 3, with group l lowest. Feed efficiency responded in a similar way to weight gain. Mortality for all groups was insignificantly different. At the end of the experiment, uniformity for commercial chickens was best in group 3, followed by group 2, with group 4 worst. Dressing, breast and thigh percentages were not evidently different. Comprehensive valuaion led to the conclusion that a maximal response was observed to the nutrition level in group3.