初配月龄对荷斯坦奶牛头胎产奶量的影响

Effect of First Breeding Monthage on Milk Yield\= in Dairy Holstein Firstcalf Heifer

对西宁市奶牛场９７头荷斯坦奶牛不同初配月龄与头胎产奶量的关系进行了统计分析。结果表明，１７．０～１７．９月龄初配受孕的奶牛头胎产奶量最高，比１６．９月龄以前初配受孕的高５４２．４５ｋｇ（Ｐ＜０．０５），比１８．０～１８．９月龄初配受孕的高５２０．４１ｋｇ（Ｐ＜０．０５），比１９．０～１９．９月龄初配受孕的高１０４２．０１ｋｇ（Ｐ＜０．０１），比２０．０月龄以上初配受孕的高２０１．２９ｋｇ（Ｐ＞０．０５）。说明西宁地区的荷斯坦奶牛在１７．０～１７．９月龄初配较为理想。

The relationship between first milk yield and different breeding monthage were analysized by means of statistics in 97 dairy Holstein firstcalf heifers of Xining Dairy Farm.The results showed that there was the most high milk yield in the heifers of breeding and conception at 17.017.9 monthage.It was 542.45kg higher than that of below 16.9 monthage (P<0.05),520.41kg higher than that of 18.018.9 month-age (P<0.05),1042.01kg higher than that of 19.019.9 monthage(P<0.01) and 201.29kg higher than that of over 20.0 monthage(P>0.05).The best first breeding monthage of heifer was at 17.017.9 monthage.