CONTENTS №8-2023

A brief analytical report is devoted to the general aspects of the epizootology of retroviral infections in connection with the stable unfavorable situation in productive animal husbandry, veterinary care for companion animals and many unresolved issues of science and practice in this area. The first part contains a general description of the family Retroviridae, a brief overview of pathogenetic features with special attention to the problem of the relationship between exogenous and endogenous retroviruses. Key words: retroviruses, taxonomy, endogenous retroviruses.

9 Salmakov K.M., Kosarev M.A. Improvement of the system of specific prevention of brucellosis in cattle with the use of vaccine from B. abortus strain 82 and drug from B. abortus strain R-1096

Epizootic Situation in the Russian Federation remains reasonably tense. The epizootic ill-being of animal stock for brucellosis and violations of sanitary and hygiene standards and rules of conduction of animal husbandry are main reasons of widespread infection and economic losses in the livestock agriculture. Our results show examples of the use of specific preventive medicines against brucellosis for solution of actual tasks of preventing the spread of brucellosis among farm animals. Key words: brucellosis, cattle, specific prevention of brucellosis, vaccines, differential diagnosis, control of the immune response.

15 Koteneva S.V., Nefedchenko A.V., Glotova T.I., Sudorgina T.E., Semenova O.V., Glotov A.G. Detection of BVDV-1f in a respiratory disease outbreak in calves

An outbreak of infection with a respiratory syndrome in calves between one and six months on a big dairy farm which occurs with the participation of BVDV as the primary etiological agent is described. An autopsy revealed hemorrhagic inflammation, single longitudinal erosions on the mucous membrane of the small intestine, enlargement and inflammation of regional lymph nodes, hemorrhages in the spleen, tracheitis, and acute fibrinous bronchopneumonia. Morbidity was 60-80 %, mortality was 20 %. The virus genome was identified in 60 % of the biomaterial samples. The virus was found in samples of the lungs, mediastinal and mesenteric lymph nodes (83,3 %), tonsils (75 %), spleen (66,7 %), tracheal mucosa and small intestine (58,3 %), nasal mucosa (50 %), blood (41,7 %). The bacteria Mannheimia haemolytica (41,7 %) and Pasteurella multocida A (26,2 %), highly pathogenic for white mice, were found in the lungs, tonsils, and mediastinal lymph nodes. Sequencing and phylogenetic analysis of the 5'-untranslated region (5'-UTR) of the genome of the isolated agent confirmed its belonging to the BVDV-1f subtype, new for Russia. Given the high genetic variability of the virus, research is needed to isolate new subtypes of the pathogen and study their virulence in naturally susceptible animals. To optimize control measures and select vaccines, a promising direction is to determine the level of cross-antigenic and genetic links between virus subtypes. Key words: calves, bovine viral diarrhea, virus, subtypes, polymerase chain reaction, phylogenetic analysis.

21 Baryshnikova E.I., Senina M.E., Sindryakova I.P., Belov S.V., Slivko I.A., Lunitsin A.V. A kit for detection of rabbit hemorrhagic disease virus (RHD) and RHD type 2 by Real Time RT-PCR

This article is aimed at presenting the results of the development and validation of a kit for detection and differentiation of rabbit hemorrhagic disease virus (RHDV) and RHDV type 2 by Real Time RT-PCR. A kit was tested on a panel of biomaterial samples containing both positive and negative samples of RHDV and RHDV type 2. The analytical sensitivity of the de kit is 0,5±0,1 lg LD₅₀/cm³ for both pathogens. The coefficient of variation of intra-laboratory precision under repeatability conditions is 1,7 – 3,0 %, of intra-laboratory precision under reproducibility – 1,6 – 2,0 %. We would like to emphasize that one of the advantages of the kit under consideration is that the amplifiers of both plate and rotor types can be applied to perform Real Time RT-PCR. Another benefit of the kit is that a declaration of conformity has been obtained. Taking everything into consideration the kit is recommended for laboratory diagnostics of RHD and RHD 2 in specialized veterinary laboratories. Key words: virus, rabbit hemorrhagic disease (RHD), reverse transcription, PCR.

29 Sizov D.A., Sizov A.A., Efremova E.A., Stebleva G.M., Donchenco N.A. Development of an enzyme-linked immunosorbent diagnostic test system based on Toxocara canis cavity fluid antigens and determination of its effectiveness in diagnosing dog toxocarosis

The possibility of using Toxocara canis cavity fluid antigens in creating a laboratory model of immunoenzyme diagnostic test system that reveals class G immunoglobulins specific to Toxocara canis in the blood of carnivores was investigated. Examination of the effectiveness of the created model of ELISA in laboratory conditions showed its high diagnostic effectiveness for determining Toxocara canis specific immunoglobulins of class G in dogs blood serum. Key words: Toxocara canis, ELISA, diagnostic effectiveness.

34 Korochkina E.A., Finageev E.Yu., Glavazkaya D.E., Pushkina V.S. The evaluation of sperm quality before and after cryopreservation

The aim of the research is to assess the quality indicators of sheep sperm before and after cryopreservation. According to the results of the morphological evaluation of ram spermatozoa before and after cryopreservation, a trend towards a decrease in the number of normal spermatozoa was observed during deep freezing and thawing of sperm. Thus, the cryopreservation process causes significant ultrastructural damage to ram spermatozoa, which negatively affects their viability and reduces the likelihood of fruitful insemination during artificial insemination of sheep. A pronounced positive effect of the OptiXcell diluent (IMV, France) on the viability of spermatozoa before cryopreservation was revealed. Key words: ram spermatozoa, cryopreservation, evaluation of sperm quality.

38 Malakhova L.S., Omarov A.A., Surov A.I., Karpova E.D., Halimbekov Z.A. Results of using Surfagon to increase the efficiency of goat insemination

New technologies for the creation of highly active synthetic analogues of sex hormones contribute to the development of methods for managing the reproductive system of farm animals. The article presents the results of the use of the drug "Surfagon" (JSC "Mosagrogen") to improve the efficiency of insemination of goats. The introduction of the drug to goats at a dose of 15 mcg on the day of insemination in spontaneous estrus during the sexual season contributes to an increase in fertilization by 12 % and fertility by 33.3 %. Key words: goats, goat-producer, zaanen breed, artificial insemination, sexual season, Surfagon, fertilization, fertility.

42 Vertiprakhov V.G., Sedletskaya E.S., Latynina E.S., Polina S.I., Sadikhov E.F. Rabbit body response to intramuscular injection of trypsin

The reaction of the organism to intramuscular injection of trypsin 3 mg/kg weight diluted with physiological solution and 5% novocaine solution was studied in chinchilla rabbits. We found that injection of trypsin combined with physiological solution reduced the rate of cardiac contractions by 9,0 % (p<0,05) after the injection, and by 20,1% (p<0,05) after 30 minutes. The enzyme activity in the blood after 90 minutes of the experiment increased by 108% as compared with the control group, which indicates the enzyme entering the blood and its stimulating effect on the parasympathetic nervous system. Application of Novocaine 5 % solution as a solvent and anaesthetic reduces the influence of the preparate on blood circulation in rabbits which is proved by the index of the enzyme activity in blood that differs from the control group level by 33,8 %. Key words: rabbits, trypsin, intramuscular injections, arterial pressure in rabbits, novocaine.

46 Gorlov I.F., Balyshev A.V., Starikov N.M., Abramov S.V., Golovin V.V. Comparative pharmacokinetic study of two drugs for veterinary use based on doxycycline Doxitart 500 and Misoxin^® in broilers

The article presents the results of studies on the study on broiler chickens of the bioequivalence of two drugs in the form of powders for oral administration - the domestic Doxytart 500, developed by the Scientific and Production Association "Uralbiovet" (Russia), and the reference Misoxin^®, produced by the company Eurovet Animal Health BV (Netherlands). Currently, these drugs containing doxycycline as an active ingredient are used in the veterinary medicine of the Russian Federation for the treatment of bacterial animal diseases. Within the framework of this work, two groups of experimental broiler chickens were formed, which were orally administered the test preparations. Blood serum was obtained from birds, in which the pharmacokinetics of doxycycline were studied. Based on the obtained results, Doxytart 500 and Misoxin^® were recognized as bioequivalent drugs in terms of pharmacokinetic distribution in the blood of birds and comparability of the main pharmacokinetic parameters. Key words: bacterial infection, bioequivalence, doxycycline, poultry, broiler, pharmacokinetics.

51 Vasiljeva K.A., Lebedeva E.K., Gavrikov A.V. Features of quality control of pharmaceutical substances by manufacturers of finished products

This article discusses the problem of high financial costs of domestic manufacturers in the analysis of input control of pharmaceutical substances and excipients. It describes the types of analysis, the scope of research and various ways to reduce costs that manufacturers use. The main legitimate option to reduce the cost of analysis is the proper approval of the raw material supplier. Assistance in this can be provided distributors with qualified personnel, experience, and knowledge of foreign markets for pharmaceutical raw materials and materials and carrying out their wholesale purchases. Key words: substance, manufacturer, veterinary products, quality control, approved supplier, distributor.DOI:10.30896/0042-4846.2023.26.8.51-56

LABORATORY PRACTICE

58 Balashova E.A., Zhivoderov S.P., Lunitsin A.V. Achievements in obtaining preparations of concentrated and purified virus – a representative of Ortobunyaviruses

The article presents data characterizing three methods used to obtain preparations of purified and concentrated Akabane disease virus. The preparations were characterized by titer in serological tests. When using virus purification methods from tissue mouse virus-containing materials using acetone and freon, Akabane disease virus preparations were characterized by relatively low titers in serological reactions. The most active preparation was obtained from the cultured virus-containing material using differential centrifugation. The drug was used to obtain polyclonal blood sera from animals naturally susceptible to the Akabane disease virus. Key words: culture preparation of Akabane disease virus, tissue brain preparation, cell culture, differential centrifugation.

DOI:10.30896/0042-4846.2023.26.8.58-62