放牧补饲条件下牛体重动态变化

Dynamic Changes of Body Weight of Cattle under Grazing with Supplementary Feeding Mode

为了研究内蒙古科尔沁草地放牧牛的体重在一年中的变化规律,在放牧+补饲的饲养方式下,采用逐月称重分析犊母牛、周岁母牛、二岁母牛和成年母牛的体重变化。结果表明:除当年母犊外,其他年龄组牛于5月体重开始增长,10月达到峰值,至翌年4月末基本处于掉膘阶段,体重变化呈单峰曲线,且体重增减趋势基本一致;放牧牛均有一个明显的日增重高峰期,成年母牛和当年母犊峰值在7月份出现,分别是0.779kg/d和1.843kg/d,二岁母牛和一岁母牛的峰值在8月份出现,分别为0.98kg/d和1.477kg/d;当年母犊开始减重期出现在12月份(-0.025kg/d),其他牛开始减重期出现在11月份,体重下降率的排序为:成年母牛>一岁母牛>二岁母牛>当年母犊。

Seasonal dynamics changes of body weight of grazing cattle in Horqin grassland was obtained by the method of monthly weighting.The results showed that except for the female calves born that year, the cows at other ages began to gain weight gradual from May and reached the peak in October. And till the next April it was always in the state of losing weight. The variation of weight shows a mono-peak curve, and the tendency of gain and lose weight was approximately the same.Grazing cows all had a obvious peak of daily gain, the peak of adult cows and female calves born that year appeared at July, which were 0.779 kg/d and 1.843 kg/d respectively. The peak of cows at two years and one year old cow appeared in August, which were 0.98 kg/d and 1.477 kg/d respectively. The lose weight period of the female calves born that year began in December(-0.025 kg/d).Other cows began in November. The ranking of decrease rate of body weight: adult cow>one year old cow >two years old cow >calves born that year.