Abstract. Bactencins belong to the bovine cathelicidin family of proteins, and their role in the body is significant. The study analyzed the relationship between polymorphisms within the CATHL2 and CATHL3 genes encoding the Bac–5 and Bac–7 proteins. The study included a herd of Polish Holstein-Friesian cows of the black-and-white breed. Tests were conducted using the PCR-RFLP method with the introduction of the ACRS modification. The study showed that different genetic variants within the polymorphisms studied were significantly associated with selected parameters of milk performance, such as milk yield (P ≤ 0.01), fat (P ≤ 0.01), protein (P ≤ 0.01 and P ≤ 0.05) and lactose (P ≤ 0.01 and P ≤ 0.05) content and somatic cell count (P ≤ 0.01 and P ≤ 0.05).
Abstract. This study comprised 136 meat samples (m. longissimus lumborum) from 136 pork carcasses of six-month-old crossbred porkers derived from ♀ (Polish Large White x Polish Landrace) x ♂ (Duroc x Pietrain), with an average carcass weight of 85.8 ± 8.5 kg, slaughtered on an industrial processing line. The pH1, pH24, pH48, WHC, colour parameters (L*, a*, b*), moisture content, crude protein, intramuscular fat, and water-soluble protein content were determined. Significantly high correlation coefficients between the proportion of water-soluble proteins in meat and crude protein and pH48, WHC, and lightness (L*) were recorded, with pH48 (measured in water extracts of meat) having the greatest effect on the proportion of water-soluble protein fractions in the meat and crude protein. In contrast, the basic chemical composition of the meat, i.e. moisture, crude protein, and intramuscular fat content, had no significant effect on the levels of water-soluble proteins. The results indicate that water-soluble proteins are a useful indicator of the quality of pork longissimus muscle.