Prevalence of growth hormone receptor gene polymorphisms and their association with milk production and fertility-related traits of cross-bred dairy cows in Sri Lanka.

This study investigated the association of selected growth hormone receptor () gene SNPs with selected fertility and milk production-related phenotypes of cross-bred dairy cows ( = 153) reared on three National Livestock Development Board farms in Sri Lanka. Selected cows were genetically screened for SNPs in the exon 08 ( = 153) and 5' upstream ( = 118) regions of the gene using the target sequencing method. The relationships between different genotypes and fertility traits (average calving interval, average number of services per conception, and age at first calving) and milk production-related traits (average total lactation yield, average lactation length, and average milk yield) were analyzed using the General Linear Model in SPSS.

Effect of and gene polymorphisms on fertility traits and milk yield of cross-bred dairy cows in Sri Lanka.

Single nucleotide polymorphism (SNP) analysis of fertility genes will be useful in improving the genetic potential of dairy cows. A population of 142 cross-bred dairy cows was screened for SNPs in bovine luteinizing hormone choriogonadotropin receptor and bovine follicle stimulating hormone receptor genes. The effect of reported SNPs on selected fertility traits (average calving interval, average number of services per conception and age at first calving) and milk yield was determined.