硒和铬对蛋鸡脂质代谢及鸡蛋硒含量的影响

Effects of Selenium and Chromium on Lipid Metabolism in Laying Hens and Egg Selenium Deposition

本试验旨在研究在蛋鸡日粮中添加酵母硒和吡啶羧酸铬及其互作对蛋鸡生产性能、脂质代谢及鸡蛋品质的影响。选用320只45周龄海赛克斯蛋鸡随机分为4组,每组4个重复,每个重复20只鸡,在基础日粮中分别添加0 mg/kg吡啶羧酸铬(Ⅰ组)、0.4 mg/kg吡啶羧酸铬(Ⅱ组)、0.5 mg/kg酵母硒(Ⅲ组)、0.4 mg/kg吡啶羧酸铬+0.5 mg/kg酵母硒(Ⅳ组),预饲1周,试验从46周龄持续到50周龄,试验期5周(35 d)。结果表明,Ⅲ、Ⅳ组产蛋率极显著提高,料蛋比极显著降低(P<0.01)。Ⅱ、Ⅳ组血清总胆固醇含量极显著降低(P<0.01),Ⅲ、Ⅳ组血清高密度胆固醇含量极显著升高(P<0.01)。Ⅱ、Ⅲ、Ⅳ组蛋黄中的胆固醇含量与Ⅰ组差异极显著(P<0.01)。Ⅲ、Ⅳ组与Ⅰ、Ⅱ组相比,鸡蛋硒含量极显著升高(P<0.01)。Ⅲ、Ⅳ组在试验开始到第2周末鸡蛋硒含量极显著升高(P<0.01),从第2周末到第5周末,硒含量基本稳定,4个组均进入平台期。结果显示,吡啶羧酸铬极显著降低了血清及蛋黄中的胆固醇含量。酵母硒极显著提高了产蛋率,降低了料蛋比,并降低了蛋黄中胆固醇含量,提高了鸡蛋中的硒含量。同时添加吡啶羧酸铬和酵母硒极显著提高了产蛋率,降低了料蛋比,并降低了血清及蛋黄中的胆固醇含量,提高了血清中高密度胆固醇含量和鸡蛋中的硒含量。

An experiment was conducted to study the effects of yeast selenium （SeYst）, chromium picolinate （CrPic） and their interaction on performance, lipid metabolism and egg quality of laying hens. Three hundred and twenty 45-week-old H-Sex hens were randomly assigned to four treatments with four replicates each treatment and twenty birds in each replicate. Four dietary treatments were as followings： 1） basal diet with no chromium supplementation （group Ⅰ ）; 2） basal diet ＋ 0.4 mg/kg CrPic （group Ⅱ） ; 3） basal diet ＋ 0.5 mg/kg SeYst （group Ⅲ） ; 4） basal diet ＋ 0. 4 mg/kg CrPic ＋ 0.5 mg/kg SeYst （group Ⅳ ）, respectively. The trial lasted for 35 days. The results showed that： 1） laying rate in groups Ⅲ and Ⅳ was significantly increased and ratio of feed to egg was reduced （P〈0, 01）; 2） serum cholesterol contents in groups Ⅱ and Ⅳ were significantly reduced （P〈0.01）, and serum HDL-C contents in groups Ⅲ and Ⅳ were significantly increased （P〈0. 01）; and yolk cholesterol contents in groups Ⅱ ,Ⅲ and Ⅳ were significantly reduced compared with those in group Ⅰ （P 〈0.01）; 3） egg selenium contents in groups Ⅲ and Ⅳ were significantly increased compared with those in groups Ⅰ and （P〈0.01.） ; 4） egg selenium contents in groups Ⅲ and Ⅳ were increased compared with those in group I from starting to 2^nd week, and those in groups Ⅰ-Ⅳ reached a relatively steady value from 2^nd to 5^th week of the trial. These results indicated that supplementation of CrPic reduced cholesterol contents in serum and yolk, and supplementation of SeYst reduced ratio of feed to egg and yolk cholesterol content and increased laying rate and egg selenium content. Combination of SeYst and CrPic increased laying rate, and reduced ratio of feed to egg and cholesterol contents in serum and yolk, and increasd serum HDL-C content and egg selenium content.