Genetic Parameters and Animal Model Evaluation of First Lactation 305-d Milk Yield and Energy Traits in Karan Fries Cattle

First lactation records of 351 Karan-Fries cows born to 27 bulls, having 3 or more progeny were used to evaluate sires by animal model (AM). Heritabil9ities, genetic and phenotypic correlations between the traits were estimated by univariate and bivariate linear animal models. The heritability estimates for 305 days or less milk yield (305MY), fat based energy corrected milk yield (FECMY), fat protein based energy corrected milk yield (FPECMY) and fat protein lactose based energy corrected milk yield (FPLECMY) were 0.23, 0.65, 0.11 and 0.39, respectively. There was a high (0.99) genetic and phenotypic correlation between 305MY, FECMY and FPLECMY. The high and positive genetic correlations between energy traits are indication of common genetic and physiological mechanism governing these traits. Comparison of ranks of the sires based on 305MY, FECMY and FPLECMY by animal model depicted a notab1e100 per cent level of similarity except for FPECMY in which the ranks were entirely different. There was a high heritability and genetic correlation between FECM and FPLECM. Genetic evaluation of Karan-Fries bulls based on energy corrected milk yield will increase the accuracy of selection than the conventional mil yield evaluation. It can help in mitigating the nutrition& insecurity of the country in the long run.