Marek Balcerak

Effect of taurine and gold nanoparticles on the morphological and molecular characteristics of muscle development during chicken embryogenesis

The objective of the present investigation was to evaluate the effects of taurine and Au nanoparticles on the expression of genes related to embryonic muscle development and on the morphological characteristics of muscles. Fertilised chicken eggs (n = 160) were randomly divided into four groups: without injection (Control) and with injection of Au nanoparticles (NanoAu), taurine (Tau) or Au nanoparticles with taurine (NanoAu + Tau). The experimental solutions were given in ovo, on the third day of incubation, by injecting 0.3 ml of the experimental solution into the air sack. The embryos were evaluated on the 20th day of incubation. The methods included gene expression at the mRNA and protein levels, immunohistochemistry, histology and microscopy. In groups NanoAu, Tau and NanoAu + Tau, the muscle structure and the number of muscle cells were affected. Furthermore, taurine increased fibre diameter, the total number of nuclei, the proportion of proliferating cell nuclear antigen (PCNA)-positive cells and the total cell number. Also, gene expression of basic fibroblast growth factor-2 and PCNA was downregulated. There were no significant interactions between NanoAu and taurine, indicating that NanoAu did not enhance the effects of taurine. It may be concluded that 20 days after injection, NanoAu affected some parameters of muscle development, but the most profound effects were those of taurine.

Effect of supplementation of cows diet with linseed and fish oil and different variants of β-lactoglobulin on fatty acid composition and antioxidant capacity of milk

BACKGROUND The aim of this study was to determine the influence of polymorphic variants of β-lactoglobulin in cows supplemented with linseed and fish oil on the fatty acid composition and antioxidant capacity of milk. From the herd of 320 Polish Holstein Friesian cows three groups of cows were selected according to the variants of β-LG (β-LGAA, β-LGBB, β-LGAB). During the first 7 days (the initial period) all the cows were fed the same total mixed ration (TMR) diet. From day 8 to 28,150 g fish oil and 250 g linseed (FOL) was added to the TMR diet of each cow. RESULTS The results showed that the diet supplemented with FOL was effective in reducing atherogenic and thrombogenic indices. Introducing supplementation improved the antioxidant capacity: higher concentration of C18:2cis-9 trans-11, C20:5 n-3, C22:6 n-3, bioactive whey proteins and vitamin soluble in fat has been recorded. The results showed that β-LGAA was associated with lower levels of atherogenic and thrombogenic indices and higher concentration of C22:5 n-6, phospholipids and β-carotene. β-LGBB favours a higher content of C18:1trans-11, C18:2cis-9 trans-11 and lactoferrin. β-LGAB was associated with higher concentrations of C20:5 n-3, Lysozyme, α-retinol, α-tocopherol and total antioxidant status. CONCLUSION Modification of the diet of cows with fish oil and linseed significantly influenced fatty acid composition and antioxidant properties of milk. The effect of β-LG phenotype on the fatty acid composition and antioxidant capacity of milk is variable, which could partly be the result of a β-LG phenotype × diet interaction.

Plasma leptin as a predictor for carcass composition in growing lambs

Abstract The experiment was conducted on 30 single born Polish Merino ram lambs. At the age of 112 d, 10 ram lambs were slaughtered at 20 kg (group 1), 25 kg (group 2), and 30 kg (group 3) live weight. Plasma leptin increased between 20 and 25 kg, as well as 25 and 30 kg live weight. The differences between group 1 vs. group 3 and group 2 vs. group 3 were statistically important (P < 0.001). The lack of differences in meat content of the pelvic limb between the groups and, at the same time, the lower fat content (P < 0.001) in group 1, plus the higher fat content of the two remaining groups, are evidence of the higher fatness of carcasses in groups 2 and 3. The fat tissues except the subcutaneous fat were significantly related with the leptin concentrations at slaughter. The leptin concentration of lambs slaughtered at 30 kg live weight surpassed significantly the values noted in groups 1 and 2 (P < 0.001). The correlations between leptin and body composition indicate that plasma leptin concentration at 30 kg live weight can be a predictor of body fat. The correlation of meat weight with leptin concentration has shown no statistical differences.

The effect of carcass weight on chemical characteristics and fatty acid composition of Longissimus dorsi and Semimembranosus muscles of European wild boar (Sus scrofa scrofa) meat

Abstract: The objective of this study was to investigate the effect of carcass weight on chemical characteristics and fatty acid composition of m. longissimus dorsi and m. semimembranosus of European wild boar (Sus scrofa scrofa) meat. The research was carried out on 50 wild boars shot during four battues at hunting reserves in the central part of Poland. The carcasses were divided into three groups: ≤30 kg (G1), 31–45 kg (G2), and >45 kg (G3). The protein concentration increased with carcass weight (P ≤ 0.01). The concentration of saturated fatty acids was influenced by carcass weight and was higher when weight increased. A significantly higher level of monounsaturated fatty acids (MUFA) was found in the carcasses of wild boars from G3 compared with G1 group (P ≤ 0.01). The content of C18:2n-6 was significantly lower in the lightest carcasses compared with the heaviest (P ≤ 0.05). Statistical analysis confirmed that carcasses weight significantly affected polyunsaturated fatty acids (PUFA) n-3 content. The lightest carcasses contained a significantly higher concentration of PUFA n-3 (P ≤ 0.01). In addition, in G3, the amount of C22:5n-3 was two-fold lower (P ≤ 0.01) than in G1. The research has shown that the meat quality was affected by the carcass weight, resulting better parameters in the lighter than in the heavier carcasses. Therefore, most of the culled wild boars should be squeakers and young boars after the first year of life.