Association of SNP g.3272 T/C in the leptin gene with reproductive traits in Brahman Cross and Belgian Blue Crossbred

Abstract

            This study investigates the role of single nucleotide polymorphism (SNP) g.3272 T/C in the leptin gene as a genetic marker for enhancing reproductive efficiency in Brahman Cross and Belgian Blue crossbred cattle in Indonesia. A total of 27 Belgian Blue crossbred and 10 Brahman Cross cows were evaluated for reproductive traits, including age at puberty, age at first mating, postpartum estrus (PPE), postpartum mating (PPM), and service per conception (S/C). SNP analysis was performed using PCR-RFLP with the HindIII enzyme, and verification was carried out by sequencing. Visual estrus symptoms, estrogen levels, vaginal epithelial cell distribution, and reproductive performance were all found to be significantly (P<0.05) correlated with SNP g.3272 T/C in three genotypes (TT, TC, and CC). PPE (78.50±1.29 days), age at first mating, and the youngest age at puberty (19.50±1.29 months) were all improved in Brahman Cross cattle with the TT genotype. The TC genotype of F1 Belgian Blue cattle performed the best, with the youngest PPE (75.80±1.92 days), age at first mating, and puberty (18.85±0.56 months). Both populations were in Hardy-Weinberg equilibrium, Both Brahman Cross and Belgian Blue crossbred cattle had the same Polymorphic Information Content (PIC) values, which were 0.37. These findings suggest that SNP g.3272 T/C of the leptin gene is a promising marker for genetic selection intended to improve the reproductive efficiency of crossbred cattle and advance Indonesia's sustainable livestock productivity.