No abstract

From the standpoint of scientific achievements, it has been established that not a single animal husbandry industry in the world, with the exception of poultry farming, possesses such effective potential and develops as dynamically as pig breeding. Reproductive performance of sows is one of the main factors that characterizes the efficiency of pig breeding and its profitability. Practice shows that the selection of sows for reproductive qualities works, but it is necessary to approach in a comprehensive way. The efficiency of raising the reproductive qualities of the pigs is due to the combined ability of the original parent forms that is their compatibility with different variants of cross-breeding. The aim of the study was to analyze the reproductive qualities of sows to determine the best maternal form. The reproductive indices of sows of different foreign and domestic combinations of breeds and types are compared. Six groups of animals were formed on an analogue group basis which were evaluated using performance indicators. The final evaluation was carried out using the estimation and selection indices of sow reproductive performance. Crossbred sows of Yorkshire and Landrace breeds (Yi × Li) of Irish selection showed significantly better performance indicators (P ˂ 0.001) than other breeds. They excelled as sows with the largest litter size at birth (13.73 piglets), including live litter size (13.07 piglets), litter size at weaning (11.87 piglets) and litter weight at weaning (89.74 kg). The piglets of experience groups had lower indexes of living mass both at birth and at weaning, in relation to control, that confirms the display of biological antagonism of dependence of living mass of piglets from their amount in a nest. It was established, that the influence of maternal genotype was significant (P ˂ 0.01) and was higher compared with the boar genotype factor in the reproductive performance of sows and their complex indices. It is advisable to use sows (Yi × Li) as a productive maternal form in order to obtain commercial hybrids.

Seasonality affects milk production, its composition, as well as the spread of mastitis in dairy cows. The aim of the research work was to study the way the seasons affect milk productivity and the manifestation of mastitis among Ukrainian brown Swiss cows at a commercial dairy unit, with the animals kept in naturally ventilated premises. The relationship between the indicators was assessed by Spearman’s rank-order correlation coefficient. The influence of a seasonal factor and individual air parameters on cows’ milk productivity was evaluated using Factorial ANOVA in Statistica 12 software. The results of the study revealed a high correlation between the content of milk fat and milk protein and the weather conditions (temperature, relative humidity, as well as temperature-humidity index) by seasons. Moreover, the greatest negative relationship between these characteristics was observed in spring (r = 0.4‒0.8) and in autumn (r = 0.6), and not in summer during the heat, as we had predicted earlier. The influence rate of the «season» factor was significant both in terms of the daily milk yield and milk components (51–59%) and mastitis prevalence rate in cows (56%) at the dairy unit. In general, the reduction of milk yields in summer and especially in autumn, and the spread of udder pathology in cows during this period should provide for the introduction of managerial and preventive veterinary measures to mitigate the effects of hot summer among Ukrainian Brown Swiss cows at year-round housing of animals in naturally ventilated premises.

Anthropogenic load on aquatic ecosystems leads to increased inputs of heavy metals, which can have a toxic effect on aquatic organisms. Some of the most appropriate objects for research are short-cycle fish species. This article considers the results of studies on the adaptive reactions of the stone moroko Pseudorasbora parva (Temminck et Schlegel, 1846) to Mn, Pb, Ni heavy metal ions, which exceeded the reference values in the reservoir by 1.7, 1.5 and 2.0 times, respectively. Changes in morphological parameters of the blood and histocytological pattern of the hepatopancreas of the experimental species under the influence of toxicants, as well as changes in biochemical parameters, were determined. It was noted that the influence of Mn caused pathological changes in the form of poikilocytosis. The morphometric parameters of erythrocytes (the cell area and the nuclear area) reached 67.48 ± 0.67 and 13.97 ± 0.22 µm2 respectively (4.0% and 13.8% less compared to the control). The influence of Ni resulted in an increased number of leukocytes and immature forms of erythrocytes. The area of erythrocytes was 0.9% smaller than that of the control group, and the area of the nucleus was 4.5% smaller than in the control. The effect of Pb as well as Mn consisted in poikilocytosis. The area of red blood cells and nuclei was smaller by 6.5% and 8.3%, respectively, compared to the control. The percentage of white blood cells in fish exposed to Ni and Pb tended to increase. In the experiment with nickel, the percentage of white blood cells was 10.2% of the number of formed elements; in the experiment with lead – 11.3%; with manganese – 6.1%, while in the control, the number of white blood cells compared to the total number of formed elements of fish was only 1.2%. Cytometric studies have revealed that there are significant differences in the shape, size, and location of hepatocytes in different experimental fish. The structural components of the liver for histological specimens were stained differentially with different intensities and different colours. The hepatocytes on histological specimens of the liver of the stone moroko exposed to Ni and Mn ions did not have clearly defined boundaries, there was a large number of destroyed cells, which indicates the toxic effect of these heavy metals. The hepatocytes exposed to Pb had the largest area of cells and nuclei and the highest nuclear-cytoplasmic ratio is typical for hepatocytes under the influence of Mn. The nuclei had the largest size and occupied 12.7% of the internal contents of the cells. It is shown that under the impact of the studied concentrations of Mn, Ni and Pb, lactate dehydrogenase activity increased by 1.22, 1.14 and 1.48 times compared to the control, respectively. In contrast, there was a 3.27-fold decrease in succinate dehydrogenase activity under the impact of Mn. Besides that, the activity of the enzyme decreased by 1.48 and 1.68 times under the action of Ni and Pb. Subsequently, we found an increase in the activity of alkaline phosphatase in muscle tissue by 3.25–3.94 times under the influence of the studied toxicants. Muscle protein levels under the impact of Mn were 1.14 times lower than in the control, the most distinct decrease in protein was found under the impact of Ni (1.53 times). The obtained data of physiological and biochemical reactions of the stone moroko to the influence of heavy metals provide an opportunity to predict changes in the species composition of fish fauna under conditions of excessive toxic pollution of ecosystems.

The article presents the results of analysis of the main chemical composition values (total moisture, dry matter, intramuscular fat, protein and ash contents) and physical properties (pH1, pH16, pH24, water-holding capacity) of the longest back muscle for different genotypes of pigs of different genetic combinations under two weight conditions (100 and 120 kg).It was found that the acidity levels and water-holding capacity of meat of animals from all study groups were within the limits established in the processing industry and fitted into the European category NOR (normal). Autolytic processes in the muscle tissues of high-intensity foreign genotypes are more intensive than those of native genotypes. An increase in the pre-slaughter liveweight from 100 to 120 kg had no effect on the water-holding capacity of meat, but its active acidity (pH) tended to decrease as the animals gained weight. It was found that the meat of pigs from intensive commercial genotypes of foreign selection had higher protein levels and lower fat and ash contents compared with meat of native pig breeds. With an increase in the pre-slaughter weight from 100 to 120 kg the intramuscular fat content in the meat of animals of all genotypes under study increased due to reduction in the protein and moisture levels. It was further found that the use of these genetic combinations led to a decrease in the water-holding capacity and active acidity levels. The meat of pigs produced by combination of native genotypes (UVB-1×UVB-2)×UVB-3 has the best physicochemical properties. Animals produced by mating a combination of sows (Yi ×Li ) and (Li ×Yi ) and boars of synthetic MaxGrow and MaxTer terminal lines had the highest protein levels in their meat both with the 100 kg and 120 kg pre-slaughter weight. Key words: meat, musculus longissimus dorsi, quality, physicochemical composition, terminal boars, active acidity, water-holding ability.