Authors: Zanilabdin Makpal, Ilgekbayeva Gulnaz, Otarbayev Bauyrzhan, Nissanova Raikhan, Mussayeva Gulzhan, Takai Shinji, Suzuki Yasunori, Kakuda Tsutomu, Kurman Serikzhan, Kassymov Yerken, Valiyeva Bayan
Journal: Frontiers in veterinary science
Summary
# Editorial Summary: *Rhodococcus equi* in Kazakhstani Horse Populations A cross-sectional serological and molecular investigation across three Kazakhstani regions identified *Rhodococcus equi* circulation in both adult horses and foals, with seroprevalence significantly higher in the latter group (25.0% versus 5.9%). Researchers tested sera from 312 animals across 20 farms using indirect ELISA and cultured clinical samples from affected foals, subsequently confirming three isolates through PCR and 16S rRNA sequencing. The overall seroprevalence of 8.3% disguises important age-related clustering patterns and farm-level hotspots in the Almaty region, whilst phylogenetic analysis demonstrated that Kazakhstani strains are genetically aligned (>99.5% identity) with equine-associated lineages documented in Europe and East Asia, suggesting a shared epidemiological pattern rather than a regionally distinct pathogen. For practitioners working in or with horses from Central Asia, these findings underscore the presence of this facultative intracellular pathogen as a genuine bronchopneumonia risk in foal populations and highlight the value of serological screening programmes to identify at-risk premises. However, the limited foal sample size and absence of environmental or management data mean that evidence-based recommendations for farm-level control strategies must await further investigation incorporating risk-factor analysis and broader geographic sampling across the region.
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Practical Takeaways
- •R. equi is actively circulating in Kazakhstan with foals at significantly higher risk; practitioners in affected regions should maintain awareness of clinical signs and consider screening of foals on farms with known exposure
- •The clustering pattern in Almaty suggests management or environmental factors facilitate transmission on some farms—investigate biosecurity, housing density, and foal hygiene protocols on affected operations
- •Standardized serological screening protocols validated against reference standards could help identify high-risk farms and guide targeted preventive measures
Key Findings
- •Overall seroprevalence of R. equi was 8.3% (26/312) across three Kazakhstani regions, with significantly higher positivity in foals at 25.0% versus 5.9% in adults
- •R. equi was successfully isolated and cultured from three foals, with molecular confirmation via PCR and 16S rRNA sequencing
- •Phylogenetic analysis showed >99.5% identity between Kazakhstani isolates and equine-associated R. equi strains from Europe and East Asia, indicating circulating pathogen strain consistency across geographic regions
- •Farm-level clustering of seropositivity was observed in the Almaty region, suggesting localized transmission risk factors