不同饲养模式对肉鸡血液生化、产和屠宰性能的影响

试验研究了不同的饲养模式对肉仔鸡生产性能、屠宰性能和血清酶活性的影响.试验共设3种饲养模式,分别为3层笼养、网上平养和户外散养.结果表明,笼养模式的肉鸡生长速度在前期（1～21日龄）平均日增重较高,而后期低于平养肉鸡,全期两者差异不显著（P＞0.05）.与笼养和平养肉鸡相比,散养肉鸡胫骨长度、腿肌率和皮下脂肪厚度极显著降低（P＜0.01）;而屠宰率略高（P＞0.05）.以平养方式饲养的肉鸡胸肌率最高,为34.19％ （P＜0.01）.散养模式可显著提高肉鸡血清5＇-核苷酸酶和碱性磷酸酶活性（P＜0.01）,降低血清尿素氮含量（P＜0.05）.

Effects of Different Rearing Patterns on Serum Enzyme Activity,Production Performance and Slaughtering Performance in Broilers

The experiment was studied on the comparison of different feeding manners on productivity, slaugh- tering performance, serum enzyme activity of broilers. The experiment was designed with three treatments, including cage-reared（CR）, floor-reared group（FR） and extensive-reared group（ER） individually. The results showed that the ADG of CR group was better than FR group slightly in 1-21 d, but has lower production in 22-42 d, even if the dif- ference was not significantly（P〉0.05）. Compared with the other two treatments, the ER group can decrease shank length, percentage of leg muscle and depth of subcutaneous fat significantly（P〈0.01）, but has a better dressed per- centage（P〉0.05）. The percentage of breast muscle of the broilers in FR was 34.19%, the largest in the three treat- ments（P〈0.01）. Extensive-rearing pattern can increase serum alkaline phosphatase and 5＇-nueleotidase activity（P〈 0.01）, and also reduce the content of serum urea nitrogen significantly（P〈0.05）.