中国生态农业学报Issue(12)：1453-1459,7.DOI:10.13930/j.cnki.cjea.140796
放养条件下密度和补饲量对蛋鸡生产性能及蛋黄胆固醇含量的影响
Effects of density and feed supplement on layer production and yolk cholesterol under grazing conditions
摘要
Abstract
Although the birth of ecological chicken industry was greeted with great enthusiasm, unreasonable feeding density has largely killed plant cover, exposed hill slopes bare and damaged the ecology. How to use the land resource and shade environment under trees has become a major problem requiring an urgent solution. A total of 441 healthy 45-week-old layer hens were randomly divided into 7 groups to study the effects of density and feed supplement rate on layer production and yolk cholesterol content under grazing conditions. Hens of groups 1ԟ6 were reared under jujube/alfalfa wood. Treatments were set at feed supplement rates of 50%and 70%of free ingestion and at densities of 100, 250 and 400 hens per 667 m2. The 7th group of hens was reared in cages with free ingestion. Each plot area was 62 m2, 3 replicas set up for each group and 3 plots of each group used for rotation grazing. Preliminary trial period was 7 days while normal trial period was 70 days. The results showed that while density and feed supplement interaction had significant effects on egg laying rate (P<0.01), it had no significant effect on egg weight and feed/egg ratio. Egg weight, egg laying rate and feed/egg ratio were not significantly different between cage-reared hens with free ingestion and 70%feed supplement with density of 100 hens per 667 m2 (P>0.05). However, in cage-reared hens with free ingestion, egg laying rate was significantly higher than in other treatments (P>0.05), egg weight significantly higher than in 50%feed supplement with density of 100 hens per 667 m2 (P>0.05), and feed/egg ratio significantly lower than in 50%feed supplement with density of 100 hens per 667 m2 (P<0.05). The interaction between feed supplement and density had no significant effect on yolk weight, yolk cholesterol content and egg cholesterol content (P> 0.05). However, hen density had significant effect on egg cholesterol content (P< 0.01). Yolk weight of cage-reared hens with free ingestion was significantly higher than that of hens reared under 50%feed supplement and density of 100 hens per 667 m2 (P < 0.01). Yolk cholesterol content and egg cholesterol content of cage-reared hens with free ingestion were significantly higher than those of hens reared under 50%and 70%feed supplements and density of 100 hens per 667 m2 (P<0.05). Pasture cover was highest for treatment with 70%feed supplement and density of 100 hens per 667 m2. Thus the culture mode with 70% feed supplement and density of 100 hens per 667 m2 was better for layer production, yolk cholesterol content and pasture protection.关键词
蛋鸡/林下放养/苜蓿/养殖密度/补饲量/生产性能/蛋黄胆固醇Key words
Layer/Grazing under trees/Alfalfa/Breed density/Feed supplement/Layer production/Yolk cholesterol分类
畜牧业引用本文复制引用
杨玉,孙宝盛,孙熠,卢营杰,李建慧,张俊珍..放养条件下密度和补饲量对蛋鸡生产性能及蛋黄胆固醇含量的影响[J].中国生态农业学报,2014,(12):1453-1459,7.基金项目
山西省科技攻关项目(200080311033)和山西农业大学博士科研启动基金项目(412559)资助 （200080311033）
