日粮对双向选择血浆极低密度脂蛋白肉鸡生长性能和血脂的影响

EFFECTS OF INTERACTION BETWEEN GENOTYPEAND NUTRITION ON GROWTH PERFORMANCEAND PLASMA LIPIDS IN BROILERS DIVERGENTLYSELECTED FOR HIGH OR LOW PLASMA VERYLOW DENSITY LIPOPROTEIN CONCENTRATION

对７０８只（公，母各半）５～９周龄选择一个世代的高、低脂蛋白（ＶＬＤＬ）系鸡进行不同代谢能水平、粗蛋白水平的两个品系３因子交叉的遗传－营养互作试验，以探讨品系与日粮互作对肉鸡生长性能和血脂的影响。品系、日粮粗蛋白质和代谢能间的互作对９周龄血浆极低密度脂蛋白（ＶＬＤＬ）、甘油三酯及总脂浓度有显著影响（Ｐ＜０．０１），而对血浆胆固醇浓度无明显影响。高ＶＬＤＬ系血浆ＶＬＤＬ浓度（Ｏ．Ｄ．）有随日粮粗蛋白水平的升高而降低之趋势，而低ＶＬＤＬ系无此规律。高ＶＬＤＬ系血浆总脂浓度随日粮蛋白水平的升高而降低（Ｐ＜０．０００１），而蛋白水平对低ＶＬＤＬ系血浆总脂浓度无明显影响。低ＶＬＤＬ系血浆ＶＬＤＬ浓度（Ｏ．Ｄ．）随日粮代谢能水平的升高而降低（Ｐ＜０．０００１），而高ＶＬＤＬ系无此规律。高ＶＬＤＬ系血浆甘油三脂浓度随日代谢能水平的升高而升高，而低ＶＬＤＬ系无此规律。高ＶＬＤＬ系血浆总脂浓度随日粮代谢能水平的升高而升高，而代谢能水平对低ＶＬＤＬ系血浆总脂浓度无明显影响。血浆甘油三酯和胆固醇浓度存在品系－性别互作效应（Ｐ＜０．０１，Ｐ＜０．０５）；性别与日粮蛋白水平互作对血浆ＶＬＤＬ、胆固醇和总脂浓度均有显著影响（Ｐ＜０．０?

The experiment for three factors crossed was conducted with 708 male and female broilers of 5 to 9 weeks of age at the G1 generation.The broilers were selected for high and low plasma very low density lipoprotein(H-VLDL and L-VLDL) concentration and fed on diets containing three metabolizable energy(ME) levels(13.4,12.5,11.6 MJ/kg) and three crude protein(CP) levels(22.4,19.4,16.4%) to investigate the effects of interactions among genotype,nutrition and sex on growth performance and plasma lipids levels for broilers.Interactions among line,dietary CP and ME had significant effect on plasma very low density lipoprotein(VLDL).Triglyceride and total lipids concentrations(P<0.01),and had no evident effect on plasma total cholesterol concentration at 9 weeks of age for broilers. It was showed a trend that plasma VLDL concentration of 9 weeks of age was decreased by increasing dietary CP level in H-VLDL broilers, whereas it wasn't demonstrated such a trend in L-VLDL line ones.Plasma triglyceride concentration of 9 weeks of age was decreased when dietary CP level was increased in L-VLDL line(P=0.0001),but it wasn't so in H-VLDL line .Plasma total lipids concentration was decreased with increasing,dietary CP level in H- VLDL(P<0.0001),however,it wasn't affected evidently by dietary CP levels in L-VLDL one.Plasma VLDL concentration of L-VLDL line broilers was decreased by increasing dietary ME level(P<0.0001),whereas that of H-VLDL line ones wasn't given such a trend . Plasma triglyceride concentration was increased when dietary ME level was increased in H-VLDL line(P<0.0001) ,but it wasn't so in L-VLDL line.Plasma total lipids concentration was increased with increasing dietary ME level in H-VLDL(P<0.0001),however,it wasn't affected significantly by dietary ME levels in L-VLDL one .There were interactions between line and sex on plasma triglyceride and cholesterol concentrations(P<0.01,P<0.05).Interaction between sex and dietary CP level had significant effect on plasma VLDL、cholesterol and total lipids concentrations at 9 weeks of age in broilers(P<0.01,P<0.05,P<0.01).There wasn't evident interaction between line and diet on feed conversion ratio of broilers,Interaction between dictary ME and sex,and that between line and dietary ME had significant effect on body weight at 9 weeks of age (P<0.01,P=0.05).Dietary ME had greater effect on body weighy in HF line than in LF line,and greater in females than in males.Body weight of females at 9 weeks age increased with increasing dietary ME,whereas it was not the case in males.