不同锌水平对荷斯坦种公牛精液品质及血液理化指标的影响

【研究目的】本文旨在研究不同锌水平日粮对荷斯坦种公牛精液品质和血液理化指标的影响。【方法】选取30头荷斯坦种公牛，随机分为5组，A为对照组，饲喂基础日粮，B、C、D、E组锌的添加水平分别为50、80、110、200mg/kg，试验期8个月。【结果】结果表明，（1）不同锌水平对荷斯坦种公牛精子活力、射精量、精子密度影响极显著（P<0.01）；对精子顶体完整率无显著影响(P>0.05)，能显著降低精子畸形率（P<0.05）。（2）不同锌水平对荷斯坦种公牛血清中睾酮含量影响极显著（P<0.01），对血清锌、精清锌和精清睾酮含量无显著影响(P>0.05)。（3）不同锌水平对荷斯坦种公牛精清中谷草转氨酶（GOT）活性影响极显著（P<0.01），对碱性磷酸酶（AKP）和谷丙转氨酶（GPT）活性有显著影响（P<0.05），对乳酸脱氢酶（LDH）活性无显著影响(P>0.05)；对血清中GOT和GPT活性影响极显著（P<0.01），对AKP和LDH活性无显著影响(P>0.05)。【结论】综合分析不同锌水平试验牛生理生化指标的变化，本次试验研究表明：锌的适宜添加量为110mg/kg日粮干物质。

Effects of Different Levels of Zinc on Semen Quality and Blood Biochemical Parameters in Holstein Bulls

【Objective】Thirty Holstein bulls assigned randomly to five groups was conducted to study the effect of different levels of zinc on semen quality and blood biochemical parameters.【Method】This experiment involved 5 dietary treatments, consisting of one control group fed basal diet and four levels of zinc which is 50,80,110,200mg/kg. The experimental period lasted 8 months. 【Results】The results shows that: (1) The effect of different levels of zinc on the sperm motility, ejaculate volume and the sperm concentration was extremely significant(P<0.01); but that on the acrosomal integrity of sperm was not significant(P>0.05); and zinc supplemental could reduce the percentage of abnormalities significantly(P<0.05); (2) The effect of different levels of zinc on the testosterone contents in serum was extremely significant (P<0.01); but that on serum zinc, zinc and testosterone contents in seminal plasma was not significant (P>0.05); (3)The effect of different levels of zinc on the activity of GOT in seminal plasma was extremely significant (P<0.01), but that on LDH was not significant(P>0.05) and which on AKP,GPT was significant(P<0.05); The effect on the activity of GPT、GOT in serum was extremely significant (P<0.01),but that on AKP、LDH was not significant (P>0.05). 【Conclusion】All of the variety of physiological and biochemical parameters analysed in each group indicated that the optimal supplementation of zinc was 110mg/kg by the dry matter in this experiment.