Fertility of Holstein Cows in Chengdu , China * *

Data on the use of breeding records of dairy cattle farm of Fenghuang-shan in Chengdu areas during a period of six years is systematically analyzed. The results show that Holstein heifers have their 1st estrus at an average age of 513.6±46.7 d which is not related to the calving season. Estrus mostly occurs in the months with mild ambient temperature (March… CONTINUE READING