Epizootological monitoring of some bacterial infectious diseases of animals on the territory of the Republic of Kazakhstan.

The presence of significant areas used for pastures in Kazakhstan makes it relevant to study the epizootic situation in terms of the incidence of animals during their grazing. The most frequent and dangerous diseases during this period are clostridiosis and listeriosis, which cause significant damage to livestock. Monitoring studies of the dynamics of morbidity among animals for infectious diseases during the grazing period were carried out on the basis of veterinary reporting. Bacteriological studies were carried out in a state laboratory using generally accepted microbiological methods. Analytical and statistical methods were used during the work. Monitoring studies indicate a significant spread of clostridiosis in the territory of Kazakhstan. The highest incidence rate was characterised by emphysematous carbuncle infection, which was recorded throughout the country, with an average frequency of about 40 cases per year. The incidence of braxy and anaerobic enterotoxemia occurred much less frequently and mainly in the southern regions of the country. Listeriosis was also observed only in some regions, but at the same time, a stationary focus of the disease was recorded in the Utylaut region, where cases of the disease are recorded annually. Conducted research made it possible to form the dynamics of the incidence of animals in the pasture period for these diseases, to determine the regions of the country with different intensity of the epizootic situation, as well as to carry out bacteriological isolation of a pure culture of the pathogen from samples taken in the foci of the disease. The studies made it possible to collect information on the features and mechanisms of the occurrence of diseases in the conditions of different regions of Kazakhstan and to develop a multi-vector strategy for preventive measures to eliminate animal diseases during the grazing period.

Salmonella sheep abortion: Distribution, diagnosis, and control measures.

The purpose of the study is to identify and isolate the causative agent of Salmonella sheep abortion in the sheep breeding industry of the Republic of Kazakhstan. The study aims to provide a basis for the development and testing of vaccines against salmonella sheep abortion using the isolated epizootic strains of Salmonella abortus-ovis AN 9/2 and Salmonella abortus-ovis 372 as control strains for immunogenicity testing. Biomaterials and pathologic materials were investigated of 114 abortions, dead ewes, and newborn lambs using the bacteriological method with the diagnostic purpose from 2009 to 2019. As a result of the bacteriological studies, the causative agent of salmonella sheep abortion was isolated and identified - Salmonella abortus-ovis. The study concludes that salmonella sheep abortion is a significant infectious disease that can cause massive economic losses and high mortality rates in sheep breeding. Prevention and control measures, such as regular cleaning, disinfection of premises, clinical examination, and thermometry of lambs, bacteriological studies, and vaccination against salmonella sheep abortion, are essential in reducing the incidence of the disease and increasing animal productivity.

Inactivated vaccine against Aujeszky's disease.

BACKGROUND AND AIM: The Aujeszky's disease, also known as Pseudorabies, remains one of the most problematic fulminant diseases in domestic animals, affecting the central nervous system. The study aimed to investigate the effect of an inactivated vaccine against Aujeszky's disease based on "Kordai" virus strain. MATERIALS AND METHODS: To test the inactivation of the "Kordai" strain (grown by the roller method in VNK-21/13 cell culture with an infectious titer of at least 7.5 lg TCD50/ml) which is causative of Aujeszky's disease, next-generation teotropin and propolis preparations were usedin concentrations of 0.1%, 0.08%, and 0.04%. RESULTS: As a result of comparative studies on the optimization of parameters for inactivating the "Kordai" virus strain, it was established that teotropin is a more effective inactivant than propolis. At the same time, the optimal final concentration of teotropin for inactivation was 0.1%, along with a reaction medium temperature of 37°C, pH of 7.4-7.6, and duration of inactivation of 14 h. The titer of virus-neutralizing activity (VNA) of antibodies at the pH (neutralization reactions) in vaccinated sheep of 10-12 months of age was 7.5±0.3, Ig TCID50/ml (tissue culture infectious dose 50%), and 3.5±0.3 in the cell culture VNK-21/13 (culture of Syrian hamster kidney cells). CONCLUSION: To determine colostral immunity in newborn lambs, the method of metabolic status correction was used to vaccinate lambs obtained from immune sheep 4 months after birth. The results showed that lambs obtained from immune sheep had high VNA titers. A sustained immune response in vaccinated animals was obtained after double vaccination.

Impact of geographical factors on the spread of animal brucellosis in the Republic of Kazakhstan.

In Latin and Central America and in most Asian countries, brucellosis remains an insufficiently studied disease. This study aims to determine the national and regional incidence of brucellosis among cattle (cows) and small ruminants (sheep, goats) in the Republic of Kazakhstan, as well as to identify the effect of climatic and geographical factors on the incidence rates. Thematic maps were created in an open geographic information system QGIS version 2.8. in order to identify the natural and socio-economic factors that influence the spread of the disease overlay method was used. Local cluster analysis was used in order to identify additional causes of the disease. Findings show the following values of Pearson correlation between the overall population and the number of animals infected: 0.68 for cows, p ≤ 0.005, and 0.56 for sheep and goats, p ≤ 0.03. Thus, the larger the heard in a given area, the greater likelihood of having brucellosis. Data processing reveals that Kazakhstan has almost twice as many regions good for cattle breeding as regions that are good for the small ruminants farming. The correlation variables for cattle and small ruminants are approximately the same. On the basis of the performed research the author proposes to amend the accepted methodology of epidemiology surveillance by the methods based on spatial (geographical) analysis. It is also proposed to adjust the process of breeding cattle and small ruminants considering the additional health recommendations that take into account the geographical aspects of the spread of the disease.

Phenotypic and genotypic characteristics of Brucella isolates from the Republic of Kazakhstan.

The purposes of this study were to determine phenotypic and genotypic characteristics of Brucella isolates from the Republic of Kazakhstan and to determine their biotype. The focus was laid on culture-morphological, biochemical, and biological properties of 59 Brucella isolates from primary cultures. Material was isolated from blood and tissue of serum-positive killed, dead diseased, or aborted domestic cattle from different regions of Kazakhstan where brucellosis is a common problem. Multiple-locus variable number tandem repeat analysis (MLVA) of all strains, isolated in different regions, has shown that Brucella isolates from the epizootic form two clusters. Based on the comparison with strains available in the MLVA database, B. abortus 0015/B is alike the B. abortus strains isolated from Italy and Portugal. B. melitensis 0016/B isolated from the Almaty region fits the third cluster and is alike the B. melitensis strains isolated from humans in Turkey, China, and Portugal. More than 90% of the overall B. abortus samples were isolated from the northern regions of the East and West Kazakhstan, while B. melitensis strains were registered in the southeast Kazakhstan. The most frequently recorded B. abortus biovar is biovar 3. The most frequently recorded B. melitensis biovars are biovars 1 and 3. SIGNIFICANCE AND IMPACT OF STUDY: These results contribute to a better understanding of the geographic pattern of Brucella infection in Kazakh cattle also important for developing the specific control measures. The results of current research can be used for creating a gene bank of Brucella strains circulating in Kazakhstan for producing diagnostic and therapeutic agents. The research material will be used to solve the problems of genetic characterization of Brucella species and to establish the phylogenetic relationships of strains.