【摘要】 选用9头黑白花种公牛随机分为3组:Ⅰ组根据饲养标准在基础日粮中添加维生素 A 42 IU/千克体重·头·日(对照组);Ⅱ组添加维生素 A 105 IU/千克体重·头·日;Ⅲ组添加维生素 A 210 IU/千克体重·头·日。试验期4个月。测定了公牛精液品质、精清酶活性和精清、血清中睾酮浓度的变化。结果表明:Ⅱ组能显著地提高采精量、原精活力、冻后活力和顶体完整率,降低精子畸形率,对精子密度无显著作用;Ⅲ组对精液品质有不良影响;原精清中谷草转氨酶(GOT)和乳酸脱氢酶(LDH)活性在各组间无差异(P>0.05),Ⅱ组冻后精清中 GOT 活性显著低于Ⅰ组和Ⅲ组,而 LDH 为Ⅱ组<Ⅲ组<Ⅰ组;血清睾酮浓度随维生素 A 添加量的增加而升高。更多还原

【Abstract】 9 Holstein breeding bulls were randomly divided into three groups of 3 bulls,fedfor 4 months on basal diets supplementing either （Ⅰ） 42 IU vitamin A kg^-1·bw^-1·d^-1（control）,（Ⅱ）105 IU vitamin A kg^-1·bw^-1·d^-1or （Ⅲ） 210 IU vitamin A kg^-1·bw^-1·d^-1.The results showed that volumes of ejaculate,motility of spermatozoa in-creased significantly in raw semen and after freeze-thawing,and percentage of abnor-malities decreased after freeze-thawing in groupⅡ.Semen quality in groupⅢ was de-pressed.No statistical difference was found in GOT and LDH activities of raw seminalplasma between three groups （P>0.05）.After freeze-thawing treatments GOT in group（Ⅱ）was lowest,and LDH:group（II）<group（Ⅲ）<group（Ⅰ）.Serum testosteroneconcentration increased with the enhancement of vitamin A supplementation.更多还原