【作者】 李庆云； 袁建敏； 闫磊； 张长海； 都叶华；

【Author】 LI Qingyun~1 YUAN Jianmin~1 YAN Lei~2 ZHANG Changhai~2 DU Yehua~2 1.College of Animal Science and Technology,State Key Laboratory for Animal Nutrition,China Agriculture University,Beijing 100094,China; 2.Center of Jinxing Duck,Beijing 102202,China

【机构】 中国农业大学动物科技学院,动物营养国家重点实验室； 北京金星鸭业中心；

【摘要】 为研究不同水平钴和维生素 B₁₂对北京鸭生产性能、胴体品质以及血液生理生化指标的影响,分别于夏季和冬季进行两次试验,采用2×2双因子设计,4个处理组日粮中钴和 VB₁₂的添加水平分别为：Co 0mg/kg,B₁₂ 0．025mg/kg；Co 0mg/kg,B₁₂ 0．05mg/kg；Co 2．5mg/kg,B₁₂ 0．025mg/kg；Co 2．5mg/kg,B₁₂ 0．05mg/kg。结果表明：高钴水平显著降低北京鸭死亡率（P＜0．10）,对其他生产性能没有显著影响；高 VB₁₂水平显著降低日采食量（P＜ 0．10）,有提高饲料转化率的趋势。钴对胴体品质没有显著影响；高 VB₁₂水平显著提高胸肌率（P＜0．10）,对腿率没有显著影响。高钴水平极显著提高血液红细胞数（P＜0．01）,显著提高血红蛋白含量、红细胞压积（P＜0．10）, 显著降低血浆铁含量（P＜0．10）；VB₁₂对造血机能没有显著影响。夏季试验高钴水平显著提高血浆白蛋白含量 （P＜0．10）；冬季试验高钴水平显著提高总蛋白、球蛋白含量（P＜0．10）,极显著提高红细胞受体花环率（P＜ 0．01）,有提高白蛋白含量、免疫复合物花环率的趋势；VB₁₂对体液免疫和红细胞免疫无显著影响（P＞0．10）。高钴水平和高 VB₁₂水平均显著提高血浆 VB₁₂含量（P＜0．01）。钴与 VB₁₂之间无互作效应。结果说明北京鸭可利用日粮中外源添加钴合成 VB₁₂,改善机体造血机能；日粮中添加钴能显著提高肉鸭体液免疫和红细胞免疫功能,降低死亡率。钴盐可通过合成 VB₁₂以外的途径影响造血机能和免疫机能,在北京鸭日粮中 VB₁₂含量满足需要的情况下, 额外添加钴盐仍有重要意义。更多还原

【Abstract】 The experiment was conducted to study the effects of different levels of cobalt and vitamin B₁₂ on performance, carcass quality and the physiological and biochemical indicators in Beijing ducks.A 2×2 factorial arrangement was em- ployed with two levels of cobalt （0 and 2.5mg/kg） and two levels of vitamin B₁₂（0.025 and 0.050mg/kg）.The results showed that the high cobalt diet significantly decreased the mortality（P＜0.10）.There were no significant differences of the average daily feed intake,body weight,feed conversion ratio and the rates of breast and legs of the duck between dia- tary cobalt levels and vitamin B₁₂ levels.Adding high cobalt in diet significantly increased the red blood cell （RBC）、hemo- globin （Hb） and packed cell volume （PCV） （P＜0.10）,and significantly decreased the iron content in plasma （P＜ 0.10）.The total protein （TP）,albumin （ALB）,globulin （GLB） in plasma and the C3b receptor rosette rate were signif- icantly affected by the dietary cobalt levels （P＜0.10）.Adding high cobalt in diet significantly increased the content of vi- tamin B₁₂ in plasma （P＜0.10）,and adding high vitamin B₁₂ in diet also significantly increased the content of vitamin B₁₂ in plasma （P＜0.10）.There was no interaction between the dietary cobalt levels and vitamin B₁₂ levels.更多还原