The article presents the results of a study of the effectiveness of the combined use of air ionization and essential oils in the technology of raising young calves. The purpose of the work was to veterinary and sanitary assessment of the influence of these factors on the parameters of the air environment and the physiological status of young animals in industrial animal husbandry. The research methodology was based on the principles of evidence-based veterinary sanitation and included a sanitary-hygienic, microbiological and zootechnical assessment of animal conditions. The experiment was carried out under production conditions on two groups of control and experimental calves, 15 heads each, which were under identical feeding and keeping conditions. The experimental set of measures included air ionization and dosed spraying of natural essential oils. The effectiveness of the developed approach was assessed by the dynamics of microclimatic indicators, the level of microbial contamination of the air in the respiratory zone of animals, as well as by clinical and physiological markers of the condition of calves. The experiments were carried out according to a single protocol for 20 days with replication in different seasons of the year to confirm the reproducibility of the results. It has been established that the combined use of aeroionization and essential oils has a pronounced sanitary-correcting effect on the air environment of calves. This is expressed in a decrease in microbial load and optimization of microclimate parameters, mainly relative humidity and level of sanitary comfort. The data obtained indicate a decrease in the risk of developing respiratory pathologies, as well as the formation of favorable conditions for physiological adaptation and maintenance of natural resistance of young animals.

Treponema pallidum subsp. pallidum is the causative agent of syphilis, a socially significant human infection whose incidence continues to increase in many regions of the world. Despite the availability of effective antibacterial therapy, investigation of the biology of this pathogen has long been limited by the inability to maintain its stable growth under artificial conditions. Historically, laboratory strains of T. pallidum have been maintained mainly by intratesticular passage in laboratory rabbits, which is associated with bioethical, technological and regulatory limitations. The aim of this review is to systematize current data on the development of T. pallidum in vitro cultivation systems, from the rabbit model and early tissue cultures to the Sf1Ep platform, direct isolation of modern clinical strains and the emergence of human cell-based systems. The review discusses the biological factors that make T. pallidum difficult to cultivate, including genome reduction, limited metabolic capacity, dependence on host cells and oxygen sensitivity. Long-term co-cultivation with rabbit epithelial Sf1Ep cells in TpCM-2 medium is considered a key technological stage in experimental treponemology. It is concluded that in vitro cultivation of T. pallidum should be regarded as a promising scientific and technological platform for studying pathogen physiology, host-cell interactions, antimicrobial susceptibility, reduction of dependence on animal models and development of biosafe experimental approaches.

The purpose of the research was to conduct monitoring studies for equine influenza in the Republic of Kazakhstan for 2024-2025. To study the prevalence of equine influenza virus in Kazakhstan in 2024, nasal flushing samples collected in 9 regions and equine blood serums collected in farms in 16 regions of the Republic of Kazakhstan were examined.
To establish the seroprevalence of equine influenza virus, ELISA studies of equine blood sera from different regions of Kazakhstan were conducted. Nasal flushes from horses were also examined by PCR to determine the circulation of equine influenza virus. 
ELISA and PCP studies were conducted in accordance with the approved instructions of the test kits used. When mapping, the open source GIS program ArcGIS was used.
The results of serological studies conducted in 2024 indicate the presence of antibodies against equine influenza virus in Kazakhstan. It should be noted that despite the numerous positive results of serological tests, the PCR studies did not reveal the DNA of the equine influenza virus in more than one studied sample.
Based on the results obtained and laboratory diagnostic studies conducted, we conducted a zoning of the territory of the Republic of Kazakhstan according to the epizootic situation of equine influenza for 2024-2025. As a result, the country's territories were identified as safe for equine influenza (0%) and according to risk indicators: a region with a low risk of equine influenza (1- 29%); a region with an average risk of equine influenza (30-59%) and a region with a high risk of equine influenza (60-100%).

The recombinant Omp19 protein of Brucella spp. is considered as a promising antigen for the development of diagnostic test systems and immunobiological preparations. However, obtaining its soluble form remains a significant challenge. The aim of this study was to optimize the dialysis conditions for the recombinant Omp19 protein following purification by ion-exchange chromatography.
Dialysis was performed sequentially in several buffer systems with varying compositions of salts and stabilizing components. Dialysis efficiency and protein solubility were assessed using the SDS-PAGE method, with analysis of the supernatant and pellet fractions under various storage temperature conditions. The results showed that when buffers 1-4 were used, the recombinant protein predominantly converted to an insoluble form and was detected in the pellet. To increase the protein’s solubility, the concentration of L-arginine in the dialysis buffer was optimized. It was found that using a buffer containing 880 mM Larginine ensured that the protein remained in the soluble fraction and prevented the formation of a visible pellet.
Based on these results, we recommend using 880 mM L-arginine to stabilize the recombinant Omp19 protein during purification and storage, which is of practical importance for the further use of this protein in diagnostics and biotechnology research.

Dermatophytes of the genus Trichophyton, particularly Trichophyton verrucosum, are the main causative agents of trichophytosis in cattle. Cultivation of these microorganisms on solid nutrient media is associated with several difficulties: most T. verrucosum strains have stringent vitamin requirements for growth, their cultures are frequently contaminated by bacterial microflora, and biomass and spore productivity on standard media remain insufficient for industrial vaccine production. Therefore, optimization of the basal wort agar medium through the addition of specific supplements that improve its growth-promoting properties is an important objective.
Objective. To evaluate the effects of glycerol, inositol, L-histidine, and chloramphenicol on the growth-promoting properties of wort agar during cultivation of production strains of Trichophyton verrucosum and Trichophyton mentagrophytes.
Materials and Methods. Standard wort agar was used as the basal medium. Experimental media were supplemented with glycerol (0.5-2.5%), inositol (0.005-0.1%), L-histidine (0.005-0.2 g/L), and chloramphenicol (0.01-0.05 g/L). Growth properties were assessed based on linear growth rate, sporulation intensity, and mycelial productivity.
Results. Glycerol at a concentration of 1.5-2.0% increased the linear growth rate of T. verrucosum strain No. 123 by 28.3% and mycelial productivity by 25.6% compared with the control. Inositol at a concentration of 0.02-0.03% increased the number of microconidia from 45.2 to 73.0 million/cm³. L-histidine at a concentration of 0.02-0.04 g/L exerted a moderate stimulatory effect on the growth of T. mentagrophytes. Chloramphenicol at a concentration of 0.025 g/L completely inhibited visible growth of contaminating bacterial microflora without suppressing dermatophyte growth. The combined use of these additives increased the total yield of microconidia by 53.4% compared with standard wort agar.
Conclusion. Supplementation of wort agar with glycerol (1.5-2.0% for T. verrucosum and 2.0- 2.5% for T. mentagrophytes), inositol (0.02-0.03%), L-histidine (0.02-0.04 g/L), and chloramphenicol (0.025 g/L) significantly improves the growth-promoting properties of the medium, increases the productivity of production dermatophyte cultures, and provides effective control of bacterial contamination.

Infectious bovine rhinotracheitis (IBR) and bovine viral diarrhea (BVD) are among the most common viral infections causing significant economic losses in livestock production. The efficacy of inactivated vaccines against these diseases is largely determined by the choice of an adjuvant system that ensures the formation of a pronounced and long-lasting immune response. The aim of this study was to comparatively evaluate the physical stability, safety, and immunogenicity of an experimental associated inactivated vaccine against IBR and BVD formulated with various commercial Montanide® adjuvants to substantiate the choice of the optimal adjuvant system. Experimental vaccines formulations were prepared based on inactivated virus-containing suspensions of the IBR virus strain “R-93” and the BVD virus strain “OregonC24V” using Montanide ISA 70 VG, Montanide ISA 61 VG, and Montanide GEL 01 PR adjuvants. The physical stability of the vaccines was assessed using an accelerated thermostability test, while safety and immunogenicity were assessed in a rabbit model following a single intramuscular immunization, with determination of virus-neutralizing antibody (VNA) titers in a neutralization test. All studied vaccines maintained physical stability for 10 days of incubation, did not cause clinically significant local adverse reactions, and were well tolerated. The highest VNA titers to both viruses were observed in the groups immunized with vaccines formulated with Montanide ISA 70 VG and Montanide GEL 01 PR, while antigens without adjuvant induced a less pronounced humoral immune response. This comprehensive evaluation supported the selection of Montanide ISA 70 VG as the optimal adjuvant for the domestic associated inactivated vaccine against IBR and BVD.