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.

Genetic polymorphism of prolactin and nitric oxide synthase in Holstein cattle.

Background and Aim: Bacterial and viral infections affect the welfare of animals and lead to large economic losses in dairy cattle breeding due to decreased productive indicators and increased culling rates. In modern dairy farming, farmers are looking for effective solutions to prevent and minimize infectious disease risks. To this end, the most relevant study field is the search for gene sites that impact production and health. This study aimed to determine the nature of the distribution of the relative frequencies of alleles and genotypes of polymorphic prolactin (PRL) and nitric oxide synthase (NOS2) in Holstein cows and identify the relationship of these genes with resistance to mastitis and bovine leukemia. Materials and Methods: For this study, we chose cows because infectious diseases affect the amount of lactation and milk quality. Holstein cattle with mastitis and bovine leukemia were selected. Animal genotypes were determined by restriction fragment length polymorphism (RFLP) of polymerase chain reaction (PCR) products. The results were analyzed using a nonparametric statistical method using Microsoft Excel 2010 and Statistica 6.0. Results: In healthy animals, 94 genotypes were identified for both genes under study. For bPRL, bPRL-RsaIAA (72) was the most common genotype and bPRL-RsaIBB (4) the least; for NOS2, bNOS2 -HinfIAB (47) was the most common genotype and bNOS2 -HinfIAA the least (21). In animals with leukemia, 34 genotypes were identified. For PRL, bPRL-RsaIAA (25) was the most common genotype and bPRL-RsaIBB (2) the least; for NOS2, bNOS2 -HinfIBB (17) was the most common genotype and bNOS2 -HinfIAA (3) the least. In animals with mastitis, 67 genotypes were identified. For PRL, bPRL-RsaIAA (43) was the most common genotype and bPRL-RsaIBB (6) the least; for NOS2, bNOS2 -HinfIBB (31) was the most common genotype and bNOS2-HinfIAA (7) the least. The distribution of genotypes of polymorphic bPRL and bNOS2 generally coincides, and bPRL-RsaIBB is the most common genotype. In groups of sick animals, the number of bNOS2 -HinfIAA homozygotes was lower than that of the control group. In particular, the proportion of animals with the bNOS2 -HinfIAA genotype with bovine leukemia was 8.7% and with mastitis was 10.3% compared with 22.4% in healthy animals. These data support the possible association of the bNOS2 -HinfIAA genotype with resistance to infection. The frequency of the bPRL-RsaIB allele was higher in groups of sick animals. This allele is associated with increased milk productivity, suggesting that highly productive animals are less resistant to the incidence of viral bovine leukemia and mastitis of bacterial etiology. Conclusion: DNA amplification of Holstein cattle for the polymorphic regions of PRL and NOS2 using the PCR-RFLP method revealed a possible connection between the distribution of relative allele frequencies of bPRL and bNOS2 and resistance to viral and bacterial infections. Thus, in groups of sick animals, the frequency of bPRL-RsaIBB, associated with increased milk production compared with the theoretically calculated equilibrium value was higher and the number of homozygotes bNOS2 -HinfIAA was lower than in the control group. In conclusion, animals with increased milk production were more prone to diseases, such as mastitis and bovine leukemia.

The Prevalence of Pathogens among Ticks Collected from Livestock in Kazakhstan.

Ticks carry and transmit a wide variety of pathogens (bacteria, viruses and protozoa) that pose a threat to humans and animals worldwide. The purpose of this work was to study ticks collected in different regions of Kazakhstan for the carriage of various pathogens. The collected ticks were examined by PCR for the carriage of various pathogens. A total of 3341 tick samples parasitizing three animal species (cattle, sheep and horses) were collected at eight regions of Kazakhstan. Eight tick species were found infesting animals: Dermacentor marginatus (28.08%), Hyalomma asiaticum (21.28%), Hyalomma anatolicum (17.18%), Dermacentor reticulatus (2.01%), Ixodes ricinus (3.35%), Ixodes persulcatus (0.33%), Hyalomma scupense (12.87%) and Hyalomma marginatum (14.90%). Ticks collected from livestock animals were examined for the pathogen spectrum of transmissible infections to determine the degree of their infection. Four pathogen DNAs (lumpy skin disease virus (LSDV), Coxiella burnetti, Teileria annulata, and Babesia caballi) were detected by PCR in Dermacentor marginatus, Hyalomma asiaticum, Hyalomma scupense, Hyalomma anatolicum. The infection of ticks Dermacentor marginatus and Hyalomma asiaticum collected on cattle in the West Kazakhstan region with LSDV was 14.28% and 5.71%, respectively. Coxiella burnetti was found in the ticks Dermacentor marginatus (31.91%) in the Turkestan region and Hyalomma anatolicum (52.63%) in the Zhambyl region. Theileria annulata was found in ticks Hyalomma scupense (7.32%) and Dermacentor marginatus (6.10%) from cattle in the Turkestan region. Babesia caballi was isolated only from the species Hyalomma scupense (17.14%) in the Turkestan region. There were no PCR-positive tick samples collected from sheep. RNA/DNAs of tick-borne encephalitis virus (TBEV), African swine fever virus (ASFV), Hantavirus hemorrhagic fever with renal syndrome (HFRS), and chlamydia pathogens were not found in ticks. The new data give a better understanding of the epidemiology of tick-borne pathogens and the possibility of the emergence of tick-borne animal diseases in Kazakhstan.

Evidence for flock transmission of individual subtypes and strains of avian influenza viruses: A monitoring study of wild birds in Kazakhstan.

An active surveillance study of avian influenza viruses (AIVs) in wild birds was carried out in Kazakhstan in 2018-2019. In total, 866 samples were collected from wild birds and analyzed for influenza viruses using molecular and virological tests. Genome segments of Asian, European, and Australian lineages were detected in 25 (4.6%) out of 541 waterfowl samples positive for subtype H3N8, and in two (0.6%) out of 325 H3N8 positive samples from terrestrial birds. No highly pathogenic avian influenza virus (AIV) was detected. The results indicated transmission of closely related strains or identical subtypes of AIVs by a flock-unit of migratory birds or annual cyclical pattern of subtype dominance. The simultaneous circulation of genome segments of the Asian, European and Australian genetic lineages of H3N8 AIVs in wild birds in Kazakhstan indicated the important role of Central Asia as a transmission hub of AI viruses linking the East Asian migratory flyways with European flyways and vice versa.

Mapping the risks of the spread of peste des petits ruminants in the Republic of Kazakhstan.

Peste des petits ruminants (PPR) is a viral transboundary disease seen in small ruminants, that causes significant damage to agriculture. This disease has not been previously registered in the Republic of Kazakhstan (RK). This paper presents an assessment of the susceptibility of the RK's territory to the spread of the disease in the event of its importation from infected countries. The negative binomial regression model that was trained on the PPR outbreaks in China, was used to rank municipal districts in the RK in terms of PPR spread risk. The outbreak count per administrative district was used as a risk indicator, while a number of socio-economic, landscape, and climatic factors were considered as explanatory variables. Summary road length, altitude, the density of small ruminants, the maximum green vegetation fraction, cattle density, and the Engel coefficient were the most significant factors. The model demonstrated a good performance in training data (R2  = 0.69), and was transferred to the RK, suggesting a significantly lower susceptibility of this country to the spread of PPR. Hot spot analysis identified three clusters of districts at the highest risk, located in the western, eastern, and southern parts of Kazakhstan. As part of the study, a countrywide survey was conducted to collect data on the distribution of livestock populations, which resulted in the compilation of a complete geo-database of small ruminant holdings in the RK. The research results may be used to formulate a national strategy for preventing the importation and spread of PPR in Kazakhstan through targeted monitoring in high-risk areas.

Biological characterization of Pasteurella multocida present in the Saiga population.

BACKGROUND: This study provides biochemical and molecular genetic characteristics of P. multocida isolated from dead saigas in 1988, 2010-2015 on the territory of the Republic of Kazakhstan. RESULTS: Bacteriological samples taken from carcasses of saiga antelope during mortality events recorded in West Kazakhstan in both 2010 and 2011 and in Kostanay in 2012 and 2015 confirmed the presence of P. multocida, according to morphological and biochemical characterisation. Only in the event of 2015 was the agent proven to be the causative agent of the disease observed, haemorrhagic septicaemia. In the other mortality events it is not certain if the organism was a primary aetiology or an incidental finding as confirmatory pathological investigation was not undertaken. The implemented phylogenetic analysis of ribosomal RNA 16S gene allowed us to identify Pasteurella strains isolated in 2010-2015 as P. multocida subspecies multocida. Capsular typing by PCR showed that the studied strains isolated from dead saiga in 2010, 2011, 2012 and 2015 belonged to serotype B. MLST analysis showed that these strains of P. multocida are of the capsule type B and form one clonal grouping with isolates ST64, ST44, ST45, ST46, ST44, ST47 which isolated from cases of hemorrhagic septicemia of animals in Hungary, Burma, Sri Lanka, Pakistan and Spain. Sixteen virulence genes of the five strains of P. multocida, isolated from saigas were studied using multiplex PCR. ptfA, ompA, ompH, oma87, plpB, fimA, hsf-2, pfhA, exbB, tonB, hgbA, fur, nanB, nanH and pmHAS genes were detected in all strains. The toxA gene was not identified in the studied strains. The phylogenies of these isolates is compared across saiga populations and years and the 2015 isolate was compared to that of an isolate from a disease outbreak in 1988 and the findings suggest that these isolated bacteria are stable commensals, opportunistically pathogenic, being phylogenetically uniform with very little genetic variation notable over the last 4 decades. CONCLUSION: Isolation, phenotypic and genetic characterization of the P. multocida isolates inform understanding of the epidemiology of infection in saigas and predict virulent potential of these opportunistic bacteria.