Sdudy on Production Performance of Xianan Bulls

Through the investigation on 8 semen collection Xianan bulls and 18 natural mating Xianan bulls,it was found that Xianan bulls were early maturation.No matter for frozen semen production or natural mating,the 18-month-old bull can normally reproduce healthy calves.The reproduction performance of Xianan bulls is well.The number of annual average mating cows reaches 264 heads.Annually a bull can produce 20,175 straws of freezing sperms.The number of mating cows,frozen semen production and the first pregnancy rate per bull remarkably changes with season,highest in spring and lowest in summer.