饲粮粗蛋白质水平对“京红1号”蛋鸡产蛋后期生产性能和蛋品质的影响

本试验旨在研究饲粮中不同粗蛋白质水平对"京红1号"蛋鸡产蛋后期生产性能和蛋品质的影响,以确定其适宜蛋白质水平。试验选用41周龄"京红1号"商品代蛋鸡720只,按实测粗蛋白质水平(分别为14.08%、14.53%、14.98%和15.44%)随机分为Ⅰ组、Ⅱ组、Ⅲ组和Ⅳ组,每组12个重复,每个重复15只鸡。预试期1周,正试期22周。结果表明:1)饲粮粗蛋白质水平对蛋鸡产蛋率、平均蛋重和日产蛋量影响显著(P0.05),且其均随饲粮粗蛋白质水平升高线性增加(P0.05);饲粮粗蛋白质水平对蛋鸡料蛋比影响显著(P0.05),且其随粗蛋白质水平升高线性降低(P0.05)。2)Ⅳ组蛋壳厚度显著高于Ⅰ组和Ⅲ组(P0.05);Ⅳ组蛋重显著高于Ⅰ组和Ⅱ组(P0.05),蛋重随着饲粮粗蛋白质水平升高线性增加(P0.05)。3)经济效益分析表明Ⅳ组蛋重成本最低,经济效益最佳。综合生产性能与经济效益分析,42~64周龄"京红1号"蛋鸡适宜粗蛋白质水平为15.44%,适宜蛋白质能量比为13.41 g/MJ。

Effects of Dietary Crude Protein Level on Performance and Egg Quality of Jinghong Laying Hens during Late Stage of Egg Production

The research was conducted to investigate the effects of different dietary crude protein ( CP) level on performance and egg quality of Jinghong laying hens during late stage of egg production, and to obtain opti-mum protein proportion for them.A total of 720 Jinghong laying hens aged at 41 weeks were randomly divided into groupsⅠ,Ⅱ,Ⅲ and Ⅳ with 12 replicates per group and 15 hens per replicate.The CP level in diets of four groups was 14.08%, 14.53%, 14.98%and 15.44%, respectively.The adaptation period was 1 week, and the experimental period was 22 weeks.The results showed as follows:1) there was significant difference in laying rate, average egg weight and daily egg production ( P<0.05) among different dietary CP levels, and all of them were increased linearly with dietary CP level increasing ( P<0.05) .Besides, there was significant difference in the ratio of feed to egg ( P<0.05) among different dietary CP levels, and the ratio of feed to egg was decreased linearly with the increase of dietary CP level ( P<0.05) .2) Eggshell thickness in groupⅣwas significantly higher than that of group Ⅰ and group Ⅲ ( P<0.05 ) .Compared with groups Ⅰ and Ⅱ, egg weight in groupⅥwas significantly higher ( P<0.05) , and egg weight was increased with the increasing of di-etary CP level ( P<0.05) .3) Economic analysis showed that the egg weight cost of group Ⅵ was the lowest and got the best economic benefit among all groups.In conclusion, 15.44%( CP/energy was 13.41 g/MJ) is recommended as the best CP level for Jinghong laying hens from 42 to 64 weeks of age.