The aim of the work was to compare the breeding environment in a standing stall stable and a box stall stable where horses are kept for recreation purposes. The stables were characterized by similar technical and technological solutions. Assessment of the breeding environment was performed on the basis of stable area and cubature indexes as well as microclimate measurements over the winter period. The results of the study indicate that more favourable conditions of keeping horses, in terms of their welfare, were in the box stall stable. Most microclimate characteristics in the standing stall stable (relative humidity, air movement, cooling power and lighting intensity), expressed as mean and maximum values, had too high values compared with the recommended zoohygienic standards.

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.

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.

The aim of this study was to determine correlations between changes in the levels of body energy reserves assessed based on backfat thickness and the fertility and productivity of dairy cows at the initial stage of lactation. The experiment was conducted under production conditions, in two herds of 108 Polish Holstein-Friesian Black-and-White cows. The body condition of cows was determined and backfat thickness was measured by ultrasonography at thirty-day intervals. The average differences in body fat reserves between the value obtained after calving and that corresponding to the lowest point of the lactation curve were 0.5 BCS unit, 36 kg body weight and 4.4 mm backfat thickness. The cows in which differences in backfat thickness measured postpartum and in week 9–12 of lactation remained within the 1–5 mm range were characterized by the highest fertility. Gradual mobilization of body fat reserves (1–10 mm) resulted in the highest milk yield. This suggests that intense mobilization of body energy reserves does not ensure the highest production levels.

The domestic horse karyotype is characterized by the diploid number of chromosomes that equals 64 (13 metacentric and submetacentric pairs, 18 pairs of acrocentric autosomes and a pair of heterochromosomes). Satellites on the first pair of chromosomes as well as secondary restrictions on acrocentric chromosomes 18 and 31 are visible and make it easier to identify them without banding. The aim of the study was to describe the horse karyotype in respect of the size and location of constitutive heterochromatin as well as the location and number of nucleolar organizer regions. C bands in horse chromosomes have been found in centromeric regions of all the examined chromosomes, excluding the 11. pair. Apart form a proximal band C, an additional band in the interstitial part of the q arm was found on the X sex chromosome. Forty-four per cent of the Y chromosome was made up of heterochromatin. Active NORs were identified in the terminal parts of p arm of the 1. chromosome as well as in the subcentromeric part of q arm of pairs 28 and 31. The average NOR number in a cell was 3.61±1.03. The most often observed cells had 3 or 4 active NORs.