THE EFFECT OF GENETIC VARIATIONS OF PITUITARY TRANSCRIPTION FACTOR 1 (PIT1) ON MILK PERFORMANCE TRAITS IN ROMANIAN CATTLE

The aim of this study was to investigate the HinfI polymorphism of PIT1 gene in two cattle breeds, Romanian Spotted and Romanian Brown. Genomic DNA samples were obtained from a total of 137 cattle, of which 82 were Romanian Spotted cattle (RS) and 55 Romanian Brown (RB). All the animals were reared at the Research and Development Station for Bovine, located in Arad, Romania. The cattle involved in the study were milked twice per day and were included in the official dairy control, which consists of milk records at every 28 days. Genotype analyses were performed using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. We identified three genotypes and two alleles. The frequency of the B allele was higher than A in both investigated breeds, but more pregnant in the Romanian Spotted population compared to Romanian Brown. The BB genotype recorded the highest frequency in Romanian Spotted, while in Romanian Brown, the AB genotype was superior in its frequency. However, the AA genotype had the lowest frequency in Romanian Brown and it was missing in Romanian Spotted. In our study, the AA genotype of PIT1 had a significant influence on milk fat percentage (P < 0.05) when we analysed both breeds together. Cows that carry the AA genotype recorded a higher fat percent (4.67 +/- 0.49%) compared to AB (4.04 +/- 0.40%) or BB (4.02 +/- 0.43%) individuals.

Automated summary

This study investigated the HinfI polymorphism of PIT1 gene in Romanian Spotted and Romanian Brown cattle breeds, identifying three genotypes and two alleles. The AA genotype of PIT1 gene significantly influenced milk fat percentage in both breeds, with variations in genotype frequencies observed between the two breeds.