Effect of Leptin, Pituitary Transcription Factor and Luteinizing Hormone Receptor Genes Polymorphisms on Reproductive Traits and Milk Yield in Holstein Cattle

Abstract

The aim of this study was to estimate allelic and genotypic frequencies of markers in the leptin (LEP), pituitary transcription factor (PIT-1) and luteinizing hormone receptor (LHR) genes and evaluate their effects on reproductive traits and milk yield of Holstein cattle. Data from 147 cows from department of Francisco Morazán, Honduras, were collected and PCR-Restriction Fragment Length Polymorphism (RFLP) assays were performed to characterize the PIT-1-HinfI, LEP-A59V and LHR-rs41256848 polymorphisms. To estimate the effect of genotypes on reproductive traits and milk yield fixed and mixed linear models were fitted. The frequencies of the genotypes CC, CT and TT of A59V, AA, AB and BB of HinfI, and CC, CG and GG of rs41256848 were 0.46, 0.33 and, 0.21; 0.09, 0.32 and 0.58; and 0.37, 0.61 and 0.02, respectively. The genotypes of LEP and LHR showed deviations from Hardy-Weinberg equilibrium. The A59V polymorphism was significantly associated with the calving to conception interval (CCI) (p=0.01), being the C allele HIGHLIGHTS  The CC genotype of the LEP gene decreases 28.71 days of the calving to conception interval. The AA genotype of the Pit-1 gene decreases 41.36 days the age at first calving. The CC genotype of the LEP gene decreases 13.62 days the calving interval.  A59V and HinfI loci are candidate SNPs to be validated in marker assisted programs. 2 Cañizares-Martínez, M.A.; et al.

Lactoferrin gene polymorphisms associated with clinical mastitis in Honduran Holstein cattle

“…Dairy farming in Honduras is based mainly in Holstein cattle (Bos taurus) and reproductive management includes insemination with semen from North America, mostly considering genetic merit for milk yield in sire selection [Cañizares-Martínez et al, 2021] and protein and fat breeding values.…”