天祝白牦牛生产力调查

为查清白牦牛生产力低的原因,对本地自然放牧的10群牦牛跟踪调查了3年,基本弄清了白牦牛牛群结构不合理,产犊率低是最基本的问题,在此基础上,提出了几项改进措施：公牛提前到2.5周岁出栏;基础牛群冷季采用放牧＋暖棚＋补饲的饲养方式;冷季出栏牛采用暖棚育肥待机出栏的方式。这些措施具有可行性并显示出明显的经济效益。

Investigation on Productivity of Tianzhu White Yak

Tianzhu white yak had suffered a low productivity for a long period,which seriously hampered the development of white yak.In order to figure out the cause of their low productivity,10 local groups of grazing yak were investigated for three years.The reasons for the low productivity had generally been clarified through the contrastive analysis,which was the unreasonable herd structure,and low reproductive rate.Furthermore,several improvement measures were proposed： the slaughtering age of the bulls moved up to 2.5 years old,the feeding method for the basic cattle adopting the combination of grazing,warm shed and supplementary feeding during the cold season,slaughter yaks fattened in greenhouse in cold seasons waiting for the best time.These measures had practicability and showed significant economic benefits.