CONTENTS №8-2024

The review briefly summarizes the literature data on the main advantages and disadvantages of metagenomic next generation sequencing (mNGS) of infectious agents in particular viruses that are important for veterinary medicine. Next-generation sequencing is a powerful and cutting-edge method for diagnosing viral infections in cases where conventional tests are ineffective, for scientific research to characterize the viral community in a specific environment (virome), as well as monitoring emerging animal viruses. Viral metagenomics is primarily used for research purposes and has not yet found widespread use as a diagnostic tool in clinical laboratories. A short list of viruses identified using whole-genome sequencing and having economic, zoonotic and zooanthroponotic significance is provided. Key words: diagnostics, metagenomics, NGS sequencing, animals, virome, viruses.

10 Yevglevsky A.A., Nosov S.V. Manifestations of vitamin B12 insufficiency new approaches to solving it

The drug cyanocobalamin used to compensate for B12 deficiency does not fully satisfy the needs of practical veterinary medicine. To achieve a positive result, a long course of use is required; the injections are very painful and cause a stress reaction in animals. In clinical studies on 2 groups of calves with malnutrition symptom complex, cyanocobolamin and cyanocobolamin with succinate were used. It was found that the complex of sodium succinate and cyanocobalamin provided a pronounced activation of energy metabolism. The level of bicarbonates in the blood of calves of the second group reached physiological values on the 14th day of the experiment. Improving the bicarbonate capacity of the blood is a consequence of the active involvement of under-oxidized metabolic products in energy metabolism. The inclusion of succinate in the composition of cyanocobalamin made it possible to qualitatively improve the biological activity of the drug, which significantly expands the range of their complex use in various pathophysiological conditions of animals. Key words: B12 deficiency, cyanocobalamin, succinate, calves, energy metabolism.

14 Okolelova T.M., Engashev S.V., Engasheva E.S., Struk E.A., Struk A.N. Effectiveness of FITODOC® Carnitine in the feeding of poultry of parental flock of Hyssex brown breed

The duration of use of the parent flock of chickens while maintaining high productivity and reproductive qualities depends on the genetic potential, housing conditions and feeding quality, which, unfortunately, do not always correspond to the physiological needs of the bird. Due to technological violations, over-compacted planting of poultry is often found and, as a result, insufficient feeding and watering front, temperature stresses are not uncommon during the hot season. In the northern regions, it is difficult to ensure a comfortable temperature in the poultry house in winter. Breeding poultry is given more attention than industrial laying hens, but even here there are errors that negatively affect the immune and reproductive systems of the body. In this regard, complex preventive drugs regulating metabolism have appeared. These include FITODOC® Carnitine, consisting of L-carnitine, betaine hydrochloride, DL-methionine and inositol. The drug was given to the parent herd of the Haysex Brown cross monthly for 5 days at a dose of 250 ml / t of water. As a result, the egg production of chickens increased by 1,0 %, egg fertilization – by 2,1 %, chick hatching – by 4,4 %. Key words: hens, roosters, FITODOC® Carnitine, productivity, egg fertilisation, chick hatching, ovary, oviduct, testes, muscular stomach.

20 Naimanov A.Kh., Vangeli E.P., Tolstenko N.G., Krasnikov N.Yu., Gulyukin A.M. M. avium subsp. paratuberculosis VIEV – a new strain for producing tuberculoproteins

The article presents a brief analysis of the problems of diagnosing paratuberculosis in cattle. In a farm that had been unaffected by paratuberculosis for a long time, the authors carried out a diagnostic slaughter of 11 cows suspected of being infected with paratuberculosis (which gave positive readings during serological and allergic studies). During a bacteriological study of pathological material from slaughtered cows, 7 cultures with slowly growing NTM were identified. During a PCR study of isolated cultures of mycobacteria, MAP was identified in 5 cows, and NTM was identified in 2 cases. As a result of a comprehensive study of cultural, morphological, antigenic properties, and whole-genome sequencing, the strain M. avium subsp. paratuberculosis VIEV B - 1402 is a tuberculoprotein producer with stable cultural, morphological and antigenic properties. Key words: cattle, paratuberculosis, mycobacteria, deposition, whole genome sequencing, PCR method, bacteriological method, M. avium subsp. paratuberculosis VIEV.

25 Marinin L.I., Mokrievich A.N., Tyurin E.A., Shishkova N.A., Dyatlov I.A. Oral method of immunization of farm animals against anthrax

The paper presents an analysis of the possibility of immunizing farm animals against anthrax by oral method. The literature and our experiments indicate the possibility of using the oral method of immunization of animals with a live anthrax vaccine at a dose 200 times higher than the dose for subcutaneous immunization. In response to vaccination, animals produce antibodies and form resistance to infection with the virulent strain of B. anthracis. However, the oral method has limitations associated with the release of a significant number of spore and vegetative cells of the vaccine strain into the external environment. Although the vaccine strain is not dangerous, its dissemination in the environment is not desirable from an environmental point of view. Key words: vaccine, anthrax, animals, prophylaxis.

30 Domatskiy V.N., Sivkova E.I. Preparations against ectoparasites of dogs and cats

Ectoparasites of dogs and cats are widespread in many regions of the Russian Federation; they pose the greatest danger as carriers of infectious and invasive diseases of animals and humans. The article presents a brief overview of therapeutic drugs, describes their comparative effectiveness for various parasitoses of dogs and cats, indicates the timing of the onset of the therapeutic effect and the duration of the prophylactic period. Key words: dogs, cats, ectoparasites, vectors, drugs, effectiveness.

36 Lazarev M.V., Shkil N.A. Effect of Bioferron on slaughter and liver morphology of quail

The inclusion of iron chelate complex in the diet of quails has a positive effect on the slaughter rates and liver morphology of quail. There is an increase in the mass of the carcass, internal organs, and a slaughter yield increases. Vascular changes in the liver have been identified that affect the vessels of all calibers: from the central veins to the sinusoids. This manifests in vasodilation in the control group and vasoconstriction in the experimental quail groups. A decrease in the diameter of the central vein and the width of the sinusoid capillaries indicates an increase in the tone of the vascular wall due to an increase in the contractility of the muscular membrane under the influence of Bioferron. The lowest nuclear-cytoplasmic ratio is observed in 2 experimental groups (0.36) when Bioferron is included in the diet at a dose of 0.2 mL/kg, which is manifested by the highest functional state of hepatocytes. Key words: quail, chelate complex, Bioferron, liver, nuclear-cytoplasmic ratio.

40 Ostrenko K.S., Ovcharova A.N., Belova N.V., Koltsov K.S., Nevkrytaya N.V. The expression of interleukin and sirtuin genes in dairy-calves was studied against the background of the use of a mixture of essential oils from fennel and coriander

In the early period of ontogenesis, the digestive system of young animals is formed, especially the mucous membrane. It lines all the hollow digestive organs and represents a large contact surface, both for food and for various antigens. The results of the study showed that the feed additive based on essential oils increased the expression level of proinflammatory cytokines IL-6 and IL-8 involved in the destruction of antigens. A decrease in SIRT3 expression in the control group is associated with a low level of metabolism, including the accumulation of lipid droplets inside the cell. The consequence of this is a decrease in energy supply and survival of the body. The active expression of the SIRT3 gene in the experimental groups reflects the factors of productivity growth and nonspecific resistance of dairy-calves. The data obtained confirm that the tested feed additive based on fennel and coriander essential oils has a pronounced immunostimulating effect and activates the nonspecific resistance of calves. Key words: cytokines, sirtuins, expression, immunity, metabolism, dairy-calves.

45 Marzanova S.N., Devrishov D.A., Shukurova E.B., Sidorova O.I., Marzanov N.S. Molecular genetic testing of mutant CD18G, SLC35A3T, FANCIBY alleles in cattle

The article presents the results of using DNA diagnostics of hereditary diseases in Holstein breeds and their crosses. Earlier we patented methods of detection of normal CD18A, SLC35A3G, FANCYTY and mutant CD18G, SLC35A3T, FANCYBY. The frequency of occurrence of genotypes formed by these alleles was studied. Using test-systems, it becomes possible to identify carriers and thereby stop the spread of mutant alleles, which creates an opportunity to form healthy stock of Holstein breed and its crosses. Key words: cattle, breeds, mutations, CD18G, SLC35A3T, FANCIBY, locus, genotypes, alleles.

51 Sindryakova I.P., Baryshnikova E.I., Belov S.V., Lunitsin A.V. Alternative samples in PCR diagnosis of RHDV infection

The article presents the results of a study on samples from the organs and swabs of rabbits that died from RHDV. Pathological material collected at different time intervals after the animals' death was used as the research material, along with alternative samples for laboratory diagnosis. The data on the examination of swabs from the animals' mucous membranes are provided. Key words: RHDV, RHDV type 2, diagnosis, qRT-PCR.

DOI:10.30896/0042-4846.2024.27.8.51-56

56 Novichkova E.M. Optimal time for infection of chick embryos

Chicken embryos (CE) are a unique object of research for laboratory diagnostics, isolation and cultivation of viruses, titration of virus-containing material, development and testing of drugs, diagnosis and prevention of various infectious diseases. Several generations of scientists have been studying the periodization (periods of development) of embryos, and by now we have a fairly detailed description of the successive stages of their development. Having analyzed and summarized the available information, taking into account the biochemical characteristics of the tissues of embryos of different ages, the author suggests cultivating viruses on ECs 7 –10 days old from the beginning of incubation; in exceptional cases, 5 – 6 day old embryos can be used. For experiments based on infection specific to poultry, in particular to chickens, it is advisable to select chicken embryos at the age of 11 – 13 days. When working with CE, it is necessary to take into account the “critical points” of embryogenesis, during which a high natural waste of embryos is detected: 4 – 5 days and 14 – 15 days from the beginning of incubation. Key words: chicken embryos, periodization of embryogenesis, organogenesis, cultivation of viruses, infection of chicken embryos.

DOI:10.30896/0042-4846.2024.27.8.56-60