不同粗蛋白水平对平养白羽肉种公鸡繁殖性能的影响

Effect of crude protein levels on reproductive performance of white feather broiler breeders

试验旨在研究日粮不同粗蛋白水平对平养白羽肉种公鸡繁殖性能的影响,探究日粮不同粗蛋白水平对肉种公鸡体况的改变情况。试验选用同批出雏、体重相近的24周龄罗斯308种公鸡6000只,随机分为4组,每组1500只公鸡。试验采用单因素完全随机试验设计,设置4组不同粗蛋白含量的日粮,分别为11.52%、12.07%、12.51%、12.98%。试验预试期1 w,正式试验期15 w。结果表明,12.07%粗蛋白组平养肉种公鸡体况和繁殖性能表现最好,12.51%粗蛋白组和12.07%粗蛋白组差异不大,但其饲料成本略高。11.52%粗蛋白组,虽体重、胸肌发育较理想,但是羽毛、腿和脚趾评分等较低。12.98%粗蛋白组,羽毛、腿和脚趾评分不错,但是种公鸡体重、胸肌偏大,影响其交配能力,最终导致繁殖能力不理想。研究表明,从受精率、体况发育等方面综合评价,在代谢能11.51 MJ/kg时,平养肉种公鸡的适宜粗蛋白水平为12.0%~12.5%;代谢能水平有改变时,依据代谢能水平的变化调整粗蛋白质的水平,保证合理的能蛋比。

The experiment studied the effect of different crude protein(CP)levels in diet on the reproductive performance of flat white feather broiler cocks,and to explore the effects of different CP levels in diet on the body condition of broiler cocks,then on the reproductive performance.In the experiment,6000 roosters of 308 species of Roth,hatched from the same batch and with similar body weights,were selected and randomly divided into four groups with 1500 roosters in each group.The single factor completely randomized experimental design was adopted in the experiment.Four groups of CP diets were set up,which were 11.52%,12.07%,12.51%and 12.98%,respectively.The pre-feeding period was 1 w,and the formal trial period was 15 w.The results showed that 12.0%CP level was the best for the body condition and reproductive performance of flat white feather broiler cocks.There was no significant difference between 12.51%CP group and 12.07%CP group,but the feed cost of 12.51%CP group was slightly higher.In the 11.52%CP group,although the body weight,breast muscle development were good,but its feather,legs and feet score was poor.In the 12.98%CP group,although the feather,legs and feet scores were good,the weight and breast muscles of the broiler cocks were too large,which affected their mating ability and ultimately led to their poor reproductive ability.From the comprehensive evaluation of fertilization rate and body condition development,it is suggested that the suitable level of CP is 12.0%~12.5%when the metabolizable energy is 11.51 MJ/kg,and when the metabolizable energy level is changed,the level of CP is adjusted according to the level of metabolizable energy to ensure a reasonable energy-protein ratio.