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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). Heritabilities, 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 notable100 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 nutritional insecurity of the country in the long run.

Selection of high fertile bulls with the help of marker assisted selection has gained importance in recent years. The low heritability of fertility traits hampers improvement of these traits by conventional selection based on phenotypic records. No information is available on the role of SNPs in KiSS1 gene in cattle on semen quality parameters in bovines. KiSS1 genes code for Kisspeptin, which are essential upstream regulators of neurons secreting gonadotropin-releasing hormone and play crucial role in reproduction.The coding regions along with exon-intron boundaries of KiSS1 gene, was characterized using PCR-SSCP method and direct sequencing. Two genotypes were observed which were represented as SSCP pattern 1 and pattern 2 and found to carry one SNPs (T153C) and one insertion of G at 291_292bp. The bulls with pattern 2 were heterozygous with respect to the transition T153C and pattern1 bulls were homozygous with TT genotype. The transition was predicted to cause amino acid change from Valine to Alanine. The frequency of bulls with pattern1 and pattern 2 were 0.67 and 0.33 in 67 Holstein Friesian bulls and 0.73 and 0.27 in 13 Khillari bulls. The association study of genotypes with semen quality parameters revealed significant association of genotypes with acrosome integrity in fresh semen (P<0.05) and no association with sperm concentration, volume per ejaculate, percent live sperm and Hypo Osmotic Swelling Test (HOST) with higher acrosome integrity in bulls with pattern2. Upon validation of the results in larger population and identifying the exact role of the novel SNP T153C and insertion of G at 291_292bp, they could be incorporated in selection programme for improving fertility in bulls.as markers for acrosome integrity in cattle.

This study was performed to investigate the polymorphisms in the ABCG2 (ATP-binding cassette sub-family G member 2) gene and to reveal the association of genotypes with breeding value (BV) for first lactation milk yield and milk composition traits of Karan Fries (HF crossbred) cattle. The traits were adjusted against the significant effect of non-genetic factors. PCR-RFLP analysis of ABCG2 (exon 14) gene revealed three genotypes. AA genotype in ABCG2 gene had significant effect on BV for average test day fat percentage. The identified potential genetic marker could be used for the development of Marker Assisted Selection (MAS) strategy for higher milk yield and milk composition traits in Karan Fries Cattle.