Survey of Anaplasma ovis and Anaplasma capra species in sheep in the Gevaş district of Van province by molecular methods.

Olmez I. Survey of Anaplasma ovis and Anaplasma capra Species in Sheep in the Gevaş District of Van Province by Molecular Methods. University of Van Yuzuncu Yıl, Health Science Institute, Veterinary Faculty, Department of Parasitology, MSci Thesis, Van, 2025. Tick-borne diseases cause significant economic losses in livestock production worldwide. One of the most important diseases affecting ruminants and contributing to these losses is anaplasmosis. However, there is a lack of data on the prevalence of this pathogen in livestock in eastern Turkey. In this context, the present study aimed to determine the prevalence of Anaplasma ovis and Anaplasma capra in sheep from the Gevaş district of Van province and to perform molecular characterisation of the detected strains based on specific gene targets. For this purpose, blood samples were taken randomly from 200 clinically healthy sheep via the jugular vein using EDTA-containing tubes. The presence of A. ovis and A. capra in the collected samples was investigated using conventional and nested PCR methods targeting the msp4 (major surface protein 4) and gltA genes, respectively. Of the 200 samples analysed, 149 (74,5%) tested positive for A. ovis based on amplification of an 852 bp fragment of the msp4 gene. In contrast, no samples were found positive for A. capra. Statistical analyses showed no significant association between A. ovis infection and host factors such as sex and age (P > 0,05). However, when considering the sampling regions, the prevalence of A. ovis was found to be significantly higher in the İnköy region (P < 0,05). The presence of partial msp4 gene sequences was confirmed by Sanger sequencing, and these sequences were submitted to the GenBank database (accession numbers PV231424-PV231428). Sequence analysis indicated that the A. ovis isolates did not show significant genetic diversity compared to strains reported from other countries. This study provides valuable data on the phylogenetic and molecular classification of A. ovis and A. capra in sheep in the Gevaş district of Van province. The results report a remarkably high prevalence of A. ovis infection in the region, while A. capra infection was not detected in any of the animals examined. Further studies are warranted to evaluate the epidemiology and potential impact of A. capra, which has recently been described as a novel species within the Anaplasma genus.