北方寒区奶牛饲养环境对产奶量的影响及不同胎次与产奶性能相互关系的探讨

EFFECT OF RAISING ENVIRONMENT IN NORTHERN COLD AREA ON MILK YIELD AND RELATIONSHIP OF DIFFERENT FOETUS TIMES AND LACTATION CAPACITY IN HOLSTEIN COWS

为了探讨北方高寒地区奶牛的饲养环境对泌乳量的影响以及不同胎次与泌乳性能之间的关系,以八五一一农场为试验基地,主要研究了全年月泌乳量与月平均温度之间的关系,同时还研究了奶牛不同胎次与全期泌乳量、泌乳天数、305 d泌乳量和乳脂率之间的相互关系。研究结果表明,在一年中从一月份至十二月份每个月的平均泌乳量类似抛物线变化,随着奶牛胎次的增加,泌乳天数呈逐渐提高的趋势,胎次与泌乳天数的相关系数为r=0.8184;奶牛全期泌乳量和305 d泌乳量除第3胎稍有降低外,其他随着胎次的逐渐增加,呈现一致性升高的变化趋势,不同胎次之间比较差异极显著(p<0.01),其相关系数分别为r1=0.9660,r2=0.9596。而乳脂率随着胎次的逐渐增加,呈渐进性升高的趋势,不同胎次之间比较差异极显著(p<0.01),r=0.9855。

In order to observe the influence of raising environment in northern cold area on cow抯 yield of milk and also study the relationship of different fetal times and lactation capacity, we selected all milking cows in 8511 farm to research the relationship of milk yield every month of the year and the average temperature a month, at the same time, we also studied different fetal times for concern together the whole period yield of milk. The results showed as follows: the average milk yield from January to December in a year was similar to parabolical linear, with the increase of fetal times, the lactescent days increased gradually, the coefficient of correlation of fetal times and lactescent days was 0.8184, the whole period milk yield and 305 days milk yield both had a rising tendency along with fetal times increasing, and also had a significant difference (P<0.01) between different fetal times, it抯 coefficient of correlation was r1=0.9660,r2=0.9596 respectively. And with the fetal times increased gradually, milk fat rate took a tendency of increasing gradually, among different fetal times had a significant difference (P<0.01), it抯 coefficient of correlation was r=0.9855.