饲粮代谢能和粗蛋白水平对产蛋后期双莲鸡生产性能、蛋品质和肝脏脂代谢的影响

Effects of Dietary Metabolizable Energy and Crude Protein of Diets on Production Performance,Egg Quality and Liver Lipid Metabolism of Shuanglian Chicken in Late Laying Period

试验旨在研究饲粮不同代谢能和粗蛋白水平对产蛋后期双莲鸡配套系生产性能、蛋品质、肝脏脂代谢的影响。试验选取240只健康、体重及产蛋率接近的40周龄双莲鸡产蛋母鸡,随机分为6组,每组4个重复,每个重复10只鸡。试验采取2×3双因素设计,代谢能(ME)设定为11.30和10.88 MJ/kg两个水平,粗蛋白(CP)设定为16.2%、15.2%和14.2%三个水平,预试期2周,正试期12周。结果显示:(1)粗蛋白水平对产蛋率、料蛋比、平均蛋重无显著影响(P>0.05),但11.30 MJ/kg代谢能水平可显著降低51~54周龄双莲鸡产蛋率和平均日产蛋量(P<0.05),并显著增加平均蛋重(P<0.05)。(2)饲粮代谢能和粗蛋白互作极显著影响46周龄鸡蛋蛋白高度和哈氏单位(P<0.01),并显著影响50周龄鸡蛋蛋黄颜色(P<0.05);10.88 MJ/kg代谢能水平54周龄鸡蛋哈氏单位、蛋黄比例显著高于11.30 MJ/kg代谢能水平(P<0.05),而46、54周龄鸡蛋蛋黄颜色和46、54周龄鸡蛋蛋壳厚度极显著低于11.30 MJ/kg代谢能水平(P<0.01),50周龄蛋壳厚度显著低于11.30 MJ/kg代谢能水平(P<0.05);16.2%粗蛋白水平46周龄鸡蛋哈氏单位显著高于14.2%粗蛋白水平(P<0.05),而54周龄鸡蛋蛋黄比例极显著低于15.2%和14.2%粗蛋白水平(P<0.01)。(3)10.88 MJ/kg代谢能水平双莲鸡血清、肝脏甘油三酯水平,肝脏相对重量和腹脂相对重量以及肝脏脂肪酸合成相关基因如SREBP-1c、ACACA、FAS、SCD1表达量均显著低于11.30 MJ/kg代谢能水平(P<0.01)。综合分析,本试验条件下双莲鸡配套系蛋鸡产蛋后期(42~54周龄)代谢能和粗蛋白水平分别以10.88 MJ/kg和16.2%为宜。

The experiment was conducted to study the effects of different levels of metabolizable energy and crude protein on performance,egg quality and liver lipid metabolism of Shuanglian chickens in late laying period.A total of 240 healthy 40-week-age Shuanglian laying hens with similar body weight and laying rate were randomly divided into 6 groups with 4 replicates in each group and 10 chickens per replicate.A 2×3 two-factor design was used in the experiment.The metabolizable energy(ME)was set at 11.30 and 10.88 MJ/kg,and the crude protein(CP)was set at 16.2%,15.2%and 14.2%.The pre-trial period was 2 weeks,and the experiment lasted for 12 weeks.The results showed as follows:①Dietary CP level had no significant effect on laying rate,feed to egg ratio and average egg weight,but the laying rate and daily egg mass of Shuanglian laying hens from 51 to 54 weeks of age at 11.30 MJ/kg ME level was significantly decreased,while average egg weight was significantly increased(P<0.05).②The interaction between dietary ME and CP level had a significant effect on the albumen height,Haugh unit(46 weeks of age)(P<0.01)and yolk color(50 weeks of age)(P<0.05)of eggs.The Haugh unit of eggs and yolk ratio(54 weeks of age)of eggs at 10.88 MJ/kg ME level was significantly higher than those at 11.30 MJ/kg ME level(P<0.05),while the yolk color(46 and 54 weeks of age,P<0.01)and eggshell thickness(46 and 54 weeks of age,P<0.01;50 weeks of age,P<0.05)were significantly lower than those at 11.30 MJ/kg ME level.The Haugh unit of eggs(46 weeks of age)at 16.2%CP level were significantly higher than that those at 14.2%CP level(P<0.05).In addition,the egg yolk ratio(54 weeks of age)at 16.2%CP level was significantly lower than that at 15.2%and 14.2%CP level(P<0.01).③The serum and liver triglyceride levels,relative liver weight and relative abdominal fat weight(P<0.01),and the expression of liver fatty acid synthesis related genes such as SREBP-1c,ACACA,FAS,SCD1 in laying hens at 10.88 MJ/kg ME level were significantly lower than those in hens at 11.30 MJ/kg ME level(P<0.01).In conclusion,under the conditions of this experiment,the suitable ME and CP levels of Shuanglian laying hens in the late laying period(42 to 54 weeks of age)were 10.88 MJ/kg and 16.2%,respectively.