28～56日龄湘黄鸡真可消化钙需要量的研究

Study on the True Digestible Calcium Requirement of 28～56 Days Old Hunan Yellow Broilers

在研究了28-56日龄黄鸡的真可消化钙需要量。采用单因子试验设计,将400只健康1日龄的黄鸡随机分成5个处理组,每个处理5个重复,每个重复16只鸡。以磷酸氢钙和石粉为真可消化钙的来源,分别设置了0.28%、0.38%、0.48%、0.58%和0.68%五个真可消化钙水平,进行了为期28d的养殖试验。结果表明,随着钙水平的增加,采食量和日增重有显著下降的趋势,料肉比则为先减少后增加的趋势。湘黄鸡的真可消化钙需要量,当分别以生长性能、最大胫骨灰份和最大胫骨折断力为评定指标时,分别为：0.38%,0.41%和0.45%。

The experiment was conducted to study the true digestible calcium requirement of 28- 56days old Hunan Yellow Broiler. Four hundred 1 day old female Hunan Yellow Broilers were randomly allotted into 5 treatments, 5 replicate pens of 16 birds each treatment. Broilers were fed five graded level of true digestible calcium . The graded levels of true digestible calcium were 0. 282%,0. 382%,0. 482%, 0. 582% and 0. 682%. The results indicated that, the feed intakes and the weight gains were significant affected by the true digestible calcium level. In this experiment, using optimum growth performance, tibia ash content and tibia breaking tenacity as index for evaluating the true digestible calcium requirement for 28-56days old Hunan Yellow Broilers, they were 0.38%, 0.41%and 0.45% respectively.