Effect of Age at First Calving on Milk Production and Reproductive Performance of Indonesian Holstein Dairy Cattle

The purpose of this study was to determine the milk production and reproductive performance dairy cattle in groups different ages at first calving elucidate effect age on interval Indonesian Holstein cattle. observation method use study. Records 80 cows which were born Indonesia had range 23-32 months used as materials. Cows divided into two based (AFC). Group I with 23-27 group II 28-32 months. parameters observed total yield, interval, post-partum mating, from conception, service per conception. To compare data between groups, t-tests descriptive analysis used. results showed that postpartum conception did not have a significant difference II. linear regression weak negative positive interval. In conclusion, provide reproduction