This experiment was conducted to investigate the effects of different dietary calcium ( Ca) levels on growth performance, slaughter performance, meat quality, toe quality and serum biochemical indices of frizzle chickens, and then to estimate the appropriate dietary Ca level for frizzle chickens. A total of 240 one-day-old frizzle chickens were randomly assigned to 5 groups with 6 replicates per group and 8 birds per replicate. Chickens in the 5 groups were fed the corn-soybean type diets ( available phosphorus 0. 45%, vitamin D3 1 250 IU/kg) contained 0.75%, 0.90%, 1.05%, 1.20% and 1.35% Ca, respectively. The experiment lasted for 28 days. The results showed as follows:1) dietary Ca level had significant influence on average daily gain, average daily feed intake, leg paralysis occurrence and mortality ( P<0.05) . However, the ratio of feed to gain was not significantly affected by the Ca level (P>0.05). With the increasing of Ca level, the average daily gain and average daily feed intake showed the broken-line effects ( P<0.05) . 2) Dietary Ca level had no sig-nificant influence on carcass ratio, semi-eviscerated ratio, eviscerated ratio, breast muscle ratio, thigh muscle ratio and pH, meat color and drip loss ratio of breast muscle ( P>0.05) , while the abdominal fat ratio tended to increase at first and then decrease afterwards with the increasing of dietary Ca level ( P=0.083) . Moreover, dietary Ca level had a significant influence on the breast muscle shear force (P<0.05), which showed the quadratic effect with the increasing of Ca level ( P<0.05) . 3) Dietary Ca level had significant influence on the defatted toe dry weight, the ash content and Ca content in toe ash (P<0.05), while the ash content and Ca content in toe ash showed the quadratic and broken-line effects with the increasing of dietary Ca level ( P<0.05) . 4) The serum alkaline phosphatase ( AKP) activity was not significantly affected by dietary Ca level ( P>0.05) , but the contents of Ca and phosphorus ( P) in serum were significantly affected by dietary Ca level ( P<0.05) , and the serum P content showed the broken-line effect with the increasing of dietary Ca level ( P<0.05) . In conclusion, average daily gain, average daily feed intake, breast muscle shear force, toe ash con-tent, Ca content in toe ash and serum P content are suitable for evaluating Ca requirement for frizzle chickens. Comprehensive above, the appropriate level of Ca for frizzle chickens aged from 1 to 28 days is 1.20%.%本试验旨在研究不同饲粮钙水平对麒麟鸡生长性能、屠宰性能、肉品质、趾骨特性及血清生化指标的影响，以确定麒麟鸡饲粮中钙的适宜水平。选用1日龄麒麟鸡240只，随机分为5个组，每组6个重复，每个重复8只鸡。各组分别饲喂钙水平为0.75%、0.90%、1.05%、1.20%和1.35%(可利用磷水平为0.45%，维生素D3水平为1250 IU/kg)的玉米-豆粕型试验饲粮，试验期28 d。结果表明：1)饲粮钙水平对麒麟鸡平均日增重、平均日采食量、腿病发生率和死亡率有显著影响(P<0.05)，但对料重比影响不显著(P>0.05)，随着饲粮钙水平的提高，平均日增重和平均日采食量呈断线变化(P<0.05)。2)饲粮钙水平对麒麟鸡屠宰率、半净膛率、全净膛率、胸肌率、腿肌率以及胸肌的pH、肉色和滴水损失率没有显著影响(P>0.05)，但腹脂率随着饲粮钙水平的增加有先升高后降低的变化趋势( P=0.083)。饲粮钙水平对胸肌的剪切力有显著影响(P<0.05)，且随钙水平的提高呈二次曲线变化(P<0.05)。3)饲粮钙水平对麒麟鸡趾骨脱脂干重及趾骨粗灰分、粗灰分钙含量有显著影响( P<0.05)，且趾骨粗灰分和粗灰分钙含量随着饲粮钙水平的提高呈二次曲线和断线变化( P<0.05)。4)饲粮钙水平对血清碱性磷酸酶活性影响不显著( P>0.05)，但显著影响麒麟鸡血清钙、磷含量( P<0.05)，随着饲粮钙水平的提高，血清磷含量呈断线变化( P<0.05)。综上所述，平均日增重、平均日采食量、胸肌剪切力、趾骨粗灰分和粗灰分钙含量、血清磷含量可敏感反映麒麟鸡体内钙的营养状况，综合以上敏感指标得出1~28日龄麒麟鸡饲粮中钙需要量为1.20%。
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