Sexual activity of different gilt genotype groups of the Pulawska breed during oestrus

The aim of the study was to analyze sexual activities of gilts representing various genotype groups in the RBP4 and MC4R locus. Observations of gilt behaviour during the first and the second oestrus (before initiation of the reproduction phase) were carried out in the Pulawska breed from conservation breeding. The evaluation process comprised the duration of the heat as well as the intensity of heat behaviours. Polymorphism identification in RBP4 (SNP: rs55618789) and MC4R (SNP: rs81219178) genes was performed, which resulted in the identification of three (MC4R: AA, AG and GG) and two (RBP4: CC and CT) gilt genotype groups. Significantly varying sexual activities were observed: the most intensive heat symptoms were demonstrated by CT gilts in the course of the first (P ≤ 0.05) and second (P ≤ 0.01) oestrus (locus RBP4) reaching, on average, 2.15 ± 0.13 and 2.52 ± 0.13 pt. It was further determined that the heats of CT gilts lasted longer and this difference, in the second heat, was significant (P ≤ 0.01). In the case of the MC4R locus, significant differences in gilt sexual activities were observed only in the course of the second oestrus (P ≤ 0.05). In addition, a strong association was also demonstrated of AA (locus MC4R) and CC (locus RBP4) genotypes with the thickness of the subcutaneous fat tissue (P ≤ 0.05) amounting in these gilts to 11.57 ± 0.21 mm and 11.50 ± 0.19 mm, respectively.