Abstract. The review article provides up-to-date scientific information on the characteristics, classification and mechanisms of biological action of pro-, pre- and synbiotics in the digestive tract of ruminants. The literature sources of recent years on the influence of pro-, pre- and synbiotic supplements (when adding them to the diets of ruminants) on the metabolic processes in the body, intensity of growth, development and the quality of products obtained from domestic ruminant animals are systematized and analyzed. Emphasis is placed on the fact that the degree of metabolic and productive action of these diet supplements in ruminants is determined primarily by the qualitative composition, technology of production, method of storage and quantity added to fodder. It is noted that the main mechanism of pro-, pre- and synbiotics action when entering the digestive tract of ruminant animals is optimizing the composition of its microflora, strengthening the barrier functions of the rumen, reticulum, omasum, abomasum and intestine, as well as activation of interferon synthesis by blood leukocytes, stimulation of digestive functions and strengthening immune status. Also it is stated that the use of these fodder additives in the diet optimizes the quantitative and qualitative composition of the symbiotic microbiota of the digestive tract, has an immunostimulatory effect, activates metabolic processes and improves the productive qualities of ruminants.
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.
Abstract. The aim of this study was to analyze the diameter of hair fibers collected from camels kept in Poland, and to determine differences in fiber structure between camel sexes and species. Hair samples were collected for analysis from 28 adult camels divided into groups based on sex (18 females and 10 males) and species (18 dromedary camels and 10 Bactrian camels). The samples were collected in May-July 2020, at the level of the last rib. The diameter of 42,000 fibers was measured by the modified projection microscope method. The fibers were classified into three categories: non-medullated fibers, fibers with interrupted medulla and fibers with continuous medulla. The study demonstrated that the hair fibers of camels kept in Poland had a mean diameter of 20.23 μm. Non-medullated fibers had the smallest diameter (17.32 μm). The smallest significant (P ≤ 0.05) difference in fiber diameter between males and females was noted in non-medullated fibers. Mean fiber diameter was higher in males than in females, especially in guard hair. No differences in fiber medulla diameter were found between camel sexes or species. Hair from Bactrian camels was thinner, and the proportion of non-medullated fibers was more than 50% higher than in dromedaries.
Abstract. Retinal degenerations are a series of genetically inherited diseases resulting in significant visual impairment and blindness. Among domestic cat breeds, there are degenerations of different courses associated with mutations in CEP290, CRX, AIPL1 and KIF3B genes. The aim of this study was to design diagnostic tests to identify the mutated alleles. The primers for PCR and restriction enzymes for PCR-RFLP were designed to detect mutations in genes. Mutation in the nucleotide sequence encoding AIPL1 protein causes a change in the protein structure, where a monomer is formed instead of a homodimer. Interactions of CEP290, CRX, AIPL1 and KIF3B proteins with other proteins that play a role in the proper functioning of the retina were observed. The occurring interactions between some of these proteins suggest a possible link between diseases caused by mutations of genes encoding these proteins. In other animal species, co-expression of the analyzed genes with other genes affecting retinal functions was noted.