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The data set for the estimation of genetic parameters for milk and fertility traits of 650 cows calved between 1992 and 2015 was obtained from the database of Integrated Dairies Limited, Jos, Nigeria. The analytical model included the effects of herd-year-season, sire, cow and residual effects. Sire, cow, and residual effects were random while all other effects were fixed. Heritability estimates for calving interval (CI), conception rate (CR), number of services per conception (NSC) and no return rate at 56 days (NRR56 days) were low and ranged between 0.028 (CR) and 0.166 (NSC) in the third parity. Milk yield had high heritability and repeatability estimates across parities. The coefficient of variation was highly variable and ranged from 14.86-43.67%. Thus, there was no indication of an adverse genetic relationship between fertility and milk production in this population and overall genetic parameters imply a good practical management on the Plateau will be essential for improving milk without deteriorating the efficiency of fertility traits in Holstein Friesian cattle.
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