Abstract. The aim of the present study was to evaluate the effect of leptin gene polymorphism on the fattening and slaughter performance traits in the Polish Synthetic Line 990 young boars and to estimate the frequencies of LEP/HinfI alleles and genotypes.Altogether, 205 young boars of the 990 line were included in the study. Based upon the carried out live evaluation, information was obtained in respect of following traits: body weight on day 21, 28, 70 and 180 of life; average daily gain; feed efficiency; mean backfat thickness; height of m. longissimus dorsi; percent meat content; and selection index. Genotype determination was performed using the PCR-RFLP technique. The lengths of the restriction fragments for respective alleles following digestion with HinfI were: 152 bp (allele T) and 84 + 68 bp (allele C). Two genotypes were found, TT (frequency 0.8) and TC (frequency 0.2). The analysis of relationship between different LEP genotypes and all analysed traits showed small and statistically non-significant differences.
Abstract. Oxidative metabolism is essential for the gamete and the embryo energy production and is unavoidably associated with generation of reactive oxygen species (ROS). Enzymatic antioxidant defenses are present in the mammalian oocytes, embryos and follicular fluid (FF). The protection of porcine oocytes against the oxidation stress during IVM enhanced the developmental competence after fertilization.An addition of porcine FF to maturation media have beneficial effects on the IVM and IVF results. The aim of this study was to investigate the total SOD and GSH-Px activity in the FF of gilts, considering birth status, size of follicle, season and site of the body where the ovary for pFF was collected (left or right). The ovaries were collected from a total of 263 gilts (127 nulliparae at age 6–8 month and 136 multiparae gilts at age up to 12 month). To determine SOD activity, Ransod kits were used. This method employs xanthine and xanthine oxidase to generate superoxide radicals which react with I.N.T. to form a red formazan dye. GSH-Px activity in pFF was measured using Ransel kits with hydroxycumene as substrate. In all the analyzed samples of FF SOD and GSH-Px activity was found. The activity of SOD in different seasons varied from 0.656 to 0.886 U·ml-1, and that of GSH-Px from 1277 to 2372 U·l-1. Negative correlation between SOD and GSH-Px activity in pFF was generally slender to medium. The size of follicles, birth status and site from which the ovary was taken seems to play secondary role in the GSH-Px activity, however the birth status is more important for SOD activity. The GSH-Px activity was significantly lower in winter than in the other seasons. The differences in SOD activity between the seasons were not significant. It suggest that seasonally differences in activity of antioxidant enzymes should be taken into account while collecting pFF for IVM/IVF media.