Mycoplasmosis control remains urgent in view of wide spread of bovine mycoplasmoses in the countries with intensive animal farming and trade relations between the Russian Federation and foreign partners including import of pedigree livestock and stud bull semen. Results of testing 1,186 biomaterial samples (blood, sera, nasal swabs, milk, preputial swabs, vaginal swabs, aborted and stillborn fetuses) collected from animals that demonstrated clinical signs of respiratory and reproductive disorders in 34 different regions of the Russian Federation for 2015–2018 are presented in the paper. The samples were tested with real-time polymerase chain reaction (rtPCR) for genomes of the following mycoplasmosis agents: Mycoplasma bovis, Mycoplasma bovigenitalium, Mycoplasma dispar. As a result, M. bovis genome was detected in 10.1% of the samples, M. bovigenitalium genome was detected in 8.6% of the samples and М. dispar genome was detected in 37.15% of the samples. Also, 927 semen samples submitted from Russian and foreign breeding farms were tested with PCR. Test results showed presence of M. bovis and M. bovigenitalium genomes in semen samples collected from native bull population. Presented data support Russian scientists’ conclusions on wide mycoplasmoses occurrence in cattle in the Russian Federation territory and risk of the disease agent introduction through semen import. All of these highlight the need for control of semen products as a source for mycoplasmosis spread as well as insufficiency of single testing of semen for granting the disease-free status to the breeding farm for genetic material marketing.

Viral diarrhoea is one of the most common and economically important diseases in cattle, causing significant losses in productivity and increased mortality in young livestock. Effective diagnosis of the disease requires the use of standardised sera that ensure high accuracy and reproducibility of laboratory results. Selection of sera to obtain standard sera for the diagnosis of bovine viral diarrhea represents a key challenge in the development of a standard sera panel. During monitoring in some regions of the Republic of Kazakhstan (Almaty, Mangistau, Karaganda, Turkistan oblasts) 399 samples of biomaterial from cattle were collected in private subsidiary farms and serological method of research was applied. In a serological test, specific diarrhea virus antibodies were detected in 310 serum samples. Comparative studies of sensitivity and stability of the positive sera with positive standard serum from the kit (ID Vet) were performed. During selection of sera, several factors were determined: specificity and sensitivity of the sera used, with consideration of the peculiarities of the epizootic situation in the region. This research work culminates in the production of a positive serum for the candidate from field-derived natural BVDV disease infections, and shortens the production cycle and saves costs.

Having spanned thousands of kilometers from Africa through Europe, the Middle East, Central Asia through to the south eastern part of Eurasia in the recent decade, lumpy skin disease virus has now become entrenched in China, Thailand, Vietnam, and South Korea. In light of discovered findings on recombination, cluster 2.5 lineage strains are now dominant and continue to spread throughout Southeast Asia. To gain a better picture of the phylogenetic landscape in the field, whole genome sequencing of 11 LSDV isolates from Russia and Mongolia collected from 2021 to 2023 has been attempted to see the dynamics of recombination signals, as was shown for LSDV circulating in 2017–2019 in Russia and Kazakhstan. Deep sequencing performed direct from skin nodules along with data retrieved from Genbank provides the most recent update on molecular epidemiology of LSDV and demonstrates that no more mosaic variant of LSDV has been observed, and cluster 2.5 lineage is now the dominant lineage currently on the rise in the region with its own patterns of monophyletic evolution. These discoveries may help future investigations aimed at epidemiological surveillance and virus tracking in the context of currently identified lineages worldwide.

Bovine leukemia virus (BLV) remains a major concern for cattle industries worldwide due to its persistent nature, economic impact, and challenges in control. In this study, we conducted a comprehensive nationwide survey of BLV in Kazakhstan between 2014 and 2024, utilizing serological diagnostics to assess prevalence and characterize viral genotypes (2024). A total of 433,537 serum samples were screened by agar gel immunodiffusion (AGID), revealing an overall seroprevalence of 5.87%, with the highest rates observed in the North Kazakhstan, Kostanay, and East Kazakhstan regions. In 2024, a targeted analysis of 3736 serum and 536 whole blood samples across 17 regions was performed using AGID, ELISA, real-time PCR, and nested PCR. ELISA demonstrated higher sensitivity than AGID (10.4% vs. 8.2%), confirmed by statistical correlation (r = 0.97, p < 0.001) and a Wilcoxon signed-rank test (p = 0.026). Real-time PCR detected BLV DNA in 4.7% of samples, with the highest positivity in the East Kazakhstan and Abai regions, confirming active viral circulation. Validation of a domestically developed AGID diagnostic kit showed full concordance with commercial assays (IDEXX, IDvet), supporting its use in national surveillance programs. These findings highlight the endemic status of BLV in Kazakhstan. Molecular analysis of sequenced isolates revealed the presence of genotype G-7, consistent with strains circulating in neighboring countries. Together, these results underscore the importance of integrated serological and molecular approaches for effective monitoring and control.

Introduction: Infectious bovine rhinotracheitis (IBR), caused by bovine herpesvirus type 1 (BoHV-1), remains endemic in Kazakhstan. Despite the absence of vaccination, comprehensive multi-year data on the virus circulation have been limited. Methods: A three-year surveillance between 2023 and 2025 was conducted in unvaccinated cattle from all 17 administrative regions a total of 8,590 serum samples and 4,795 nasal swabs. Serological monitoring was performed using two validated ELISA systems (IDEXX IBR gE Ab Test and ID Screen® IBR Indirect ELISA). Molecular detection employed real-time PCR on nasal swabs, and virus-isolation attempts were carried out on Vero cell monolayers. National reference serum panels were developed and externally validated at the Friedrich-Loeffler-Institut (Germany). Results: Serological testing revealed consistently high antibody prevalence—69.13% (2023), 80.64% (2024), and 82.79% (2025)—with marked regional variation. PCR positivity was 11.2% (280/2,500) in 2024 but only 0.43% (10/2,295) in 2025, indicating subclinical circulation and intermittent viral shedding. All virus-isolation attempts were negative, consistent with low viral loads and latent infection. The validated serum panels achieved > 95% concordance with international reference sera and were successfully implemented for national QA/QC. Conclusion: These findings confirm persistent BoHV-1 endemicity in Kazakhstan and highlight the diagnostic and epidemiological framework necessary for harmonized surveillance, DIVA-compatible vaccination (Differentiating Infected from Vaccinated Animals), and progressive alignment with WOAH eradication programs.

Background. Enzootic bovine leukosis (EBL) remains a significant problem in cattle production. Agar gel immunodiffusion (AGID) is widely used for screening; however, diagnostic performance depends on test-kit manufacturing parameters. Aim. To develop and optimize manufacturing conditions for an AGID test system for serological diagnosis of EBL, ensuring reproducibility and compliance with World Organisation for Animal Health (WOAH) recommendations. Methods. BLV antigen was produced on a persistently infected FLK cell line and standardized to gp51 using WOAH reference serum E05. We optimized agarose concentration (0.8–2.0% in 0.2 M Tris, pH 7.2, with 8.5% NaCl), antigen dilutions (1:2–1:64), and control sera dilutions. Plates were incubated in a humid chamber at 20–27 °C with readings at 24–72 h. Validation was performed on bovine sera (positive/weak-positive/negative) and compared with commercial kits. Results. An agarose concentration of 1.0–1.2% provided clear, stable precipitin lines within 24–72 h, balancing diffusion rate and line quality. Optimal antigen dilutions were 1:4 (eliminating nonspecific lines with negative serum while maintaining high sensitivity) and 1:8. Positive control serum was optimal at 1:4–1:8; weak-positive control at 1:32 yielded a reproducible faint line suitable for sensitivity assessment. Negative serum produced no lines. Stable performance was achieved under specified storage and operating conditions; diagnostic characteristics were comparable to those of commercial tests. Conclusions. The optimized AGID test system demonstrates high reproducibility, specificity, and adequate sensitivity, aligns with international requirements, and is suitable for broad implementation in veterinary laboratories in Kazakhstan. Accounting for regional features further enhances its practical value.