High prevalence and first molecular detection of Eucoleus garfiai in wild boars (Sus scrofa) from the central black sea region of Türkiye.

Abstract

Eucoleus garfiai is a parasitic nematode that infects the tongue epithelium of both wild and domestic suids. Despite reports from several countries, data concerning its molecular characterisation and true prevalence remain limited because detection often relies on less sensitive methods. One hundred wild boar tongues were collected from the Central Black Sea Region of Türkiye. Each tongue was divided into three sections, and the epithelial layer was meticulously examined under a stereomicroscope for parasites. Morphological identification was performed using light microscopy. Morphometric data were obtained from 209 male and 697 female specimens. Molecular confirmation was achieved by PCR amplification and sequencing of the 18 S rRNA gene of representatives from three provinces. The overall prevalence was 83% (83/100), the highest reported prevalence globally. A total of 906 parasites were collected, with a mean intensity of 10.9 parasites per infected host. The parasites were located exclusively in the anterior (62.4%) and middle (37.6%) thirds of the tongue. The morphological and morphometric features were consistent with previous descriptions of E. garfiai. Histopathological analysis revealed the presence of hyperkeratosis, parakeratosis, and a mild inflammatory infiltrate. Phylogenetic analysis of the 18 S rRNA sequences (deposited in GenBank under accession numbers PV111295, PV111296, PV111297) confirmed the identity of the isolates and revealed a distinct Turkish genotype. The prevalence of the condition was significantly higher in animals older than four years. This study reports the highest prevalence of E. garfiai to date, which is attributed to the use of a highly sensitive detection method. This study provides the first molecular characterisation and phylogenetic analysis of the parasite from Türkiye, confirming its presence with confidence. These findings underscore the necessity for refined diagnostic techniques in epidemiological studies and lay the foundation for future research on the parasite's biogeography.