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Abstract. Nowadays, meat and meat products from indigenous pig breeds are desired by consumers for their high sensory quality. For that reason, the trend to use indigenous pig breeds for production of these products has widened. The aim of this study was to compare physical and chemical parameters of Musculus longissimus dorsi (MLD) as well as content of cholesterol and fatty acid profiles among Mangalitsa, the crossbreed Mangalitsa × Duroc, and pig meat breed Slovak Large White with Polish indigenous breeds Pulawska and Zlotnicka spotted. In the study, 48 pigs were used. The pigs were divided into 5 groups of different genotypes: Mangalitsa breed (n = 9), the crossbreed Mangalitsa × Duroc (n = 9), Slovak Large White -SLW (n = 10), Zlotnicka spotted (n = 10) and Pulawska (n = 10). The pigs were reared under intensive conditions, and they were fed by an ad libitum system with complete feed mixtures. The fattening period lasted from 30 to 100 kg of live weight. The SLW had the highest average daily gain with the lowest feed intake compared to Mangalitsa, the crossbreed Ma × Du and Polish indigenous breeds (P < 0.001). SLW had the highest meat content in the carcass while Mangalitsa had the lowest (P < 0.001). Mangalitsa and their crossbreed Ma × Du had the highest fat content in the carcass, but the SLW and Polish indigenous pig breeds had the lowest fat content in the carcass (P < 0.001). As regards the physical properties of MLD, the Polish indigenous pig breeds achieved the highest values of pH 45 min post mortem, the lowest drip loss values, the lowest colour values of CIE L * and the highest values of CIE b* compared to other genotypes in the experiment (P < 0.001). However the meat of crossbreed Ma × Du had pale, soft and exudative (PSE)-like conditions due to the low pH 45 min post mortem, the high values of drip loss and CIE L * . The crossbreed Ma × Du and Polish indigenous pig breeds had the highest content of intramuscular fat in MLD compared to Mangalitsa and SLW (P < 0.001). The cholesterol content in MLD was the highest in Polish pig breeds and the lowest in SLW (P < 0.001). Regarding the fatty acid content in the meat, intramuscular fat (IMF) from Zlotnicka spotted was significantly the most polyunsaturated with the highest percentages of C18:2n-6, C20:5n-3 and C22:6n-3, and it had the lowest percentages of monounsaturated fatty acids (MUFAs) as well as contents of C18:1cis-9 and C18:1trans-11 compared to other genotypes (P < 0.001). IMF from Slovak Large White was the most saturated and monounsaturated with the highest content of C18:1cis-9, and it has the lowest percentages of polyunsaturated fatty acids (PUFAs) in IMF compared to genotypes in the study (P < 0.001). From the results, it follows that the Polish indigenous pig breeds are more suitable for the breeding and production of special meat products due to acceptable fattening and carcass parameters as well as the meat quality. As regards fatty acid composition of meat, the direct influence between fatty acid composition in diet and in Muscu...

In this study, we evaluated the impact of 5–50 μM quercetin (QUE) and naringenin (NAR) on extended boar spermatozoa in the BTS (Beltsville Thawing Solution) medium for 72 h. Spermatozoa motion, membrane, acrosome, and DNA integrity were investigated immediately after sample dilution (0 h) as well as after 24 h, 48 h, and 72 h of semen storage. Furthermore, reactive oxygen species (ROS) and superoxide production, as well as the extent of oxidative damage to the sperm proteins and lipids, were assessed to determine the potential of QUE and NAR to prevent a potential loss of sperm vitality due to oxidative stress development. Our results indicate that the most notable parameter influenced by QUE was the mitochondrial activity, which remained significantly higher throughout the experiment (p < 0.001 and p < 0.0001; 10 μM), and which correlated with the most prominent maintenance of sperm motility (p < 0.01, 48 h; p < 0.05, 72 h). A significant membrane stabilization (p < 0.01, 24 h and 48 h; p < 0.0001, 72 h) and prevention of lipid peroxidation (p < 0.05, 24 h and 48 h; p < 0.01, 72 h) was primarily observed following administration of 10 and 25 μM NAR; respectively. Administration of 10 μM QUE led to a significant decrease of superoxide (p < 0.0001, 48 h and 72 h) while the most notable decline of ROS generation was recorded in the case of 10 and 25 μM NAR (p < 0.001). This study may provide new information on the specific mechanisms of action involved in the favorable effects of natural biomolecules on spermatozoa.

Background. Differences in the types and percentages of essential amino acids (EAAs) in food could infl uence the value of protein consumed and proteins with a high content of EAAs are the most important components of poultry meat. The use of probiotics for meat and carcass quality improvement has been questioned, while feed supplementation with thyme essential oil (TEO) could be considered as useful natural supplement to be applied in the poultry industry to improve meat quality. Material and methods. Day-old broilers Ross 308 (n = 400) were randomly divided into four groups based on the feed supplement as follows: control, probiotics 0.05%, TEO 0.05% and combination of probiotics and TEO, while the fattening period was 42 days. Six birds of both sexes from each group were selected as a sample, slaughtered and then stored (-18°C) for 6 months till the analysis. The muscular homogeneous sample (50 g) from the breast and thigh of each sample bird was analysed by the Fourier Transform Infrared Spectroscopy method using the device Nicolet 6700. The essential amino acids content was determined and the quality indicators include chemical score, amino acid score, EAA index and biological value were calculated. Results. The obtained results show that for all the tested EAAs of the breast and thigh muscles, the content numerically increased gradually and progressively within the groups as the control scored the minimum followed by the probiotics group, then the combination group and fi nally the TEO group which scored the highest results. Conclusion. It can be concluded that the TEO promoted the increase of all the EAAs and consequently the quality indicators with signifi cant different compared with the control group and signifi cantly different for some EAAs and quality indicators compared with the probiotics group and the combination group.

Bacteriospermia has become a serious factor affecting sperm quality in swine breeding, this is why antibiotics (ATBs) are a critical component of semen extenders. Due to ever-increasing antimicrobial resistance, the aim of this study was to assess the efficiency of selected commercially available semen extenders to prevent a possible bacterial contamination of boar ejaculates. Three Androstar Plus extenders containing different combinations of antibiotics were used to process ejaculates from 30 healthy Duroc breeding boars. Androstar Plus without antibiotics was used as a control. The extended samples were stored at 17 °C for 72 h. Sperm motility, viability, mitochondrial activity, DNA integrity and oxidative profile of each extended sample were assessed following 24 h, 48 h and 72 h. Furthermore, selective media were used to quantify the bacterial load and specific bacterial species were identified with matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. The results indicate that semen extenders enriched with ATBs ensured a significantly higher preservation of the sperm quality in comparison to the ATB-free control. The total bacterial count was significantly decreased in the extenders supplemented with ATBs (p < 0.001), however gentamycin alone was not effective enough against Gram-positive bacteria, while a few colonies of Enterococcus hirae, Bacillus subtilis and Corynebacterium spp. were present in the samples extended in the presence of a triple combination of ATBs. In conclusion, we may suggest that semen extenders enriched in antibiotics were not able to fully eliminate the bacteria present in the studied samples. Furthermore, selection of suitable antibiotics for semen extension should be accompanied by adequate hygiene standards during the collection and handling of boar ejaculates.