热应激对荷斯坦和娟姗及娟荷杂交奶牛生产性能的影响

Effects of Heat Stress on Holstein, Jersey and Jersey×Holstein Dairy Cows

为研究热应激状况下奶牛耐热性能的表现,筛选出适宜高温高湿气候的奶牛养殖种群,试验采用分组试验设计,分为荷斯坦奶牛组、娟姗奶牛组、娟荷杂交一代(娟杂牛)奶牛组3组,每组试验奶牛15头。根据试验期间牛舍温湿指数(THI)的变化情况,进行热应激与非热应激期的对比试验。结果表明:热应激使奶牛奶产量显著下降,荷斯坦奶牛、娟姗牛、娟杂牛分别下降了26.36%、14.08%、3.49%,其中娟姗牛组的奶产量显著低于荷斯坦牛组和娟杂牛组(P<0.05);干物质采食量方面,荷斯坦牛组下降了36.47%,娟姗牛组下降了30.45%,娟杂牛组下降了31.86%;乳品质方面,娟姗牛组的乳脂、乳蛋白均显著高于荷斯坦奶牛组和娟杂牛组(P<0.05),其他乳指标虽未达到显著差异(P>0.05)但整体上呈现娟姗牛组优于娟杂牛组、荷斯坦奶牛组的趋势。综合采食量及生产性能的表现,娟杂牛可作为耐热性能较好的种群加以培育和推广。

To study the heat resistance performance of cows in heat stress and provide a theoretical basis for the screening of the dairy cow bearing the hot and humid climate,45 cows were divided into three groups and each was 15 in the principle of pilot varieties packet：Holstein cows group,Jersey cows group,the hybrid of Jersey×Holstein dairy group.The test period was carried on by non-heat stress and heat stress period according to the THI situation.The results showed that Jersey cattle milk production was significantly lower than holstein and the hybrid of jersey×holstein cattle （P〈0.05） under the heat stress; The milk yield was reduced by 26.3%,14.08% and 23.49% in Holstein,Jersey and the hybrid of Jersey ×Holstein cattle,respectively.The dry matter intake of Holstein cows in the period of heat stress raised by 36.47% in relation to non-heat stress; Jersey cow raised by 30.45%; the hybrid of Jersey × Holstein cattle raised 31.86%.The content of Jersey cattle milk fat,milk protein was significantly higher than that of the Jerseys and the hybrid of Jersey×Holstein cattle （P〈0.05）.Although other indicators were not significantly different （P〉 0.05）,the consolidated status of Jerseys was better than Jersey×Holstein and Holstein cattle was the worst.Among the comprehensive three cattle groups,Jersey ×Holstein cattle can be regarded as better heat resistance varieties for amplification and research.