The association of leptin gene polymorphism with reproductive usefulness and selected blood biochemical indicators of hybrid sows (Polish Large White × Polish Landrace)

Abstract

Rapid developments in the field of molecular genetics have led to new possibilities to identify polymorphic genes and to detect quantitative trait loci with major effects on economically important reproduction traits. Our study has defined the influence of polymorphism at position 3469 of the leptin gene on reproductive performance in sows as well as on selected blood biochemical indices in pregnant sows The research involved 173 multiparous sows after the second and third farrowing, crossbreds of Polish Large White and Polish Landrace breeds. The collected data on reproductive performance of sows concerned the number of live births, the number of weaned piglets and the length of weaning-to-estrus interval in the sows. Parities from the first to the fourth were analysed. A sample of blood was collected from each sow in the third month of pregnancy in order to isolate and then analyse DNA with the use of the PCR-RFLP methods. Blood biochemical analyses were performed as well. Two alleles of the leptin-coding gene (T and C) were found in examined herd. In the second parity, where the live birth number was concerned, the difference between the CC (10.4) and TT (9.0) leptin genotypes proved to be significant (P ≤ 0.05). Analyses of blood biochemical indices revealed virtually no significant differences between the genotypes compared. However, it was noted that the glucose concentration was the highest in the sows with TT genotype and the lowest in the sows with CC genotype.