LAUSR

In the present study, colostrum quality in Holstein cows and their genetic parameters for passive transfer traits in calves were estimated. In order to get an estimation, colostrum Brix (ColBrix), colostrum immunoglobulin G (ColIgG) of Holstein cows, and serum total protein (STP) and serum immunoglobulin G (SIgG) levels of the calves of selected cows raised in a private livestock company in Turkey were assessed. Variance components and genetic parameters were estimated by MTDFREML using a mixed model. The heritability for ColBrix, ColIgG, STP and SIgG was estimated to be 0.19 ± 0.07, 0.19 ± 0.07, 0.36 ± 0.10 and 0.34 ± 0.10, respectively. According to the results of bivariate analysis, genetic correlations between the traits varied between –0.98 and +0.98. There was a sufficient genetic variance for SIgG in the calves in the population and thus a significant genetic improvement may be achieved by selection in order to increase the passive transfer. It will be worthwhile to continue the efforts for genetic improvement studies which have the potential to reduce calf deaths in the future.