No abstract

Ecological and climatic factors have an impact on the health, productivity and reproduction of the cattle. The goal of this work is the study of physiological status of servicing bulls reared under ecological and climate conditions of the Altai region, by defining the differences between Red-Steppe, Simmental and Black-and-White breeds in spermatogenic, hormonal, biochemical and hematological parameters. Samples of peripheral blood and ejaculates were taken from 48 grown-up servicing bulls (average age 5.6±0.3 years) in autumn period. It was established that Red-Steppe bulls have higher concentrations of nonorganic phosphorus, leucocytes, erythrocytes, hemoglobin, hematocrit and erythrocyte sedimentation rate in comparison with animals of Simmental breed, and the hemoglobin concentration and hematocrit are also higher in comparison with Blackand-White breed. It was noted that bulls of Black-and-White breed have a higher level of cortisol in comparison with the other breeds. The lowest level of serum urea and total protein and increased serum activity of creatine kinase and γ-glutamyl transferase, as well as the heaviest body weight were observed in Simmental breed bulls. The differences between breeds in a wide spectrum of physiological measures reflect not only genetically determined peculiarities of homeostatic mechanism, but also may reflect different ability to adapt to local ecological and climate conditions of the Altai region. Spermatogenic, biochemical and hematological measures in bull sires reared in the Altai region were similar to those in bulls bred in other Russian regions and some other countries. The measures reported could serve as reference values and therefore represent 'normal' values of physiological status for these bull sires reared in this ecological and climatic zone, but could be utilized in further studies for comprehensive monitoring of cattle breeding stock in other ecological and climatic zones of the Siberian region of Russia.

The literature review presents the current understanding of cholesterol metabolism occurring under physiological conditions. The homeostasis of cholesterol in the body is determined by its endogenous synthesis, the transition to the cell from plasma as part of low-densitylipoproteins( LDL), the release of their cells as part of high-density lipoproteins (HDL). The molecular-genetic mechanisms of regulation of cholesterol homeostasis are described in detail. The genes for cholesterol biosynthesis in major multicellular animals were inherited from their last common eukaryotic ancestor and are evolutionarily conserved for cholesterol biosynthesis. Non-coding variants of singlenucleotide polymorphisms can significantly contribute to the phenotypic variability of cholesterol, and missense variants that lead to the replacement of amino acids in proteins can have a significant effect on the phenotypic variability. The modern aspects of cholesterol homeostasis in cattle are formed and sufficiently fully presented. During absence of exogenous intake, the balance of cholesterol in cattle is maintained by endogenous synthesis, occurring mainly in the liver, the intake of lipoproteins, as well as reverse transport mechanisms. This review gives an idea that the stability of homeostasis can be achieved only with the complex interaction of all systems (transport, enzyme, receptor) involved in this process. The analysis of the latest scientific works concerning the problem of the content and regulation of cholesterol in cow’s milk is presented. Significant single-nucleotide polymorphisms localized in the ACAT2, LDLR, DGAT, and AGPAT1 genes involved in the exchange of cholesterol in the liver or its transport and associated with the level of cholesterol in milk are described. Part of the review is devoted to cholesterol deficiency syndrome in Holstein cattle (HCD). Modern data on the prevalence, molecular and genetic basis, clinical and laboratory manifestations of the syndrome are presented.

The paper shows the results of biochemical analysis of the protein status of Kemerovo pigs. The research was carried out at OOO Chistogorskiy in Kuzbass. The blood samples from pigs were taken by means of the standard methods and analyzed in the laboratory of veterinary genetics and biochemistry of Novosibirsk State Agrarian University. The researchers used standard tools for biochemical tests on the biochemical semi-automatic analyzer Photometer 5010 V5+. The concentration of some protein metabolic parameters was characterized by a standard distribution: total protein (p-value=0.85), albumin (p-value=0.06), and globulin (p-value=0.65). The average values of total protein and albumins varied in standard intervals, except for the level of globulins, which was significantly lower than the reference values set for pigs. It was seen as one that had the greatest individual fluctuations (44%). The urea concentration was slightly lower than the physiological standard and was characterized by a rather high level of individual variability (50%). The researchers found that uric acid concentration was 3.2 times lower than the standard one in the investigated pigs. The authors observed the interbred differences in the content of total protein and albumin comparing the Kemerovo, Chistogorsk and early maturing pig breeds (CM-1). The correlation analysis has shown that there is a high positive correlation between total protein and globulins (r=0.88). The average positive relation between urea and uric acid was (r=0.58). The obtained data on protein metabolism is one of the basic characteristics of the Kemerovo pigs interior.

The results of studies of indicators of nitrogen metabolism in the blood serum of the descendants of four bulls at the age of 12-13 months are presented. The studies were conducted in the South of Western Siberia at Vaganovo OJSC on the livestock population of Holstein breed. The creatinine concentration in the blood serum samples of the sons was determined using a set of reagents from Vector-Best (Russia). In the regions of animal breeding, constant monitoring of water, soil, feed, animal organs and tissues is carried out. It was established that in the areas in which the studied breeds were bred, the content of macro- and microelements did not exceed the MPC. The level of serum creatinine in the examined animals on average for all groups of sons was 308.2 ± 24.1 μmol / L, which exceeds the generally accepted values   of this indicator. However, taking into account age and sex and breed characteristics, taking into account data on the overall health of the animals examined, information on the ecological well-being of the breeding zone, the results can be considered as reference values   for healthy Holstein bulls in Western Siberia. It was shown that in the blood serum of the sons of some fathers, the creatinine content was 1.7 times higher (364.2 ± 52.7 μmol / L) than in the descendants of other manufacturers (p> 0.95). A group of half-siblings was found, which were characterized by a low hereditary predisposition to creatinine content. Discovered differences in the creatinine content in the blood serum of sons reflect the differentiation of bulls and indicate genetically determined features of the functioning of the homeostasis system. In this case, most likely, there is a different ability of descendants to adapt to environmental and climatic conditions.