RT Journal Article T1 Molecular Evidence of the Role of the Red Fox (Vulpes vulpes) in the Epidemiology of Ungulate-Related Sarcocystis Species in Croatia, Lithuania, and Portugal A1 Gudiškis, Naglis A1 Prakas, Petras A1 Beck, Relja A1 Figueiredo, Ana A1 Juozaitytė-Ngugu, Evelina A1 Balčiauskas, Linas A1 Calero Bernal, Rafael A1 Gagović, Ema A1 Torres, Rita T. A1 Hipólito, Dário A1 Carmena, David A1 Stirkė, Vitalijus A1 Butkauskas, Dalius AB Sarcocystis spp. (Apicomplexa: Sarcocystidae) are globally distributed protozoan parasites with an obligatory two-host prey–predator life cycle involving intermediate (IHs) and definitive hosts (DHs). Canids, including the red fox (Vulpes vulpes), often serve as DHs for species infecting various ungulates. This study identified Sarcocystis species in red foxes from Croatia, Lithuania, and Portugal. Between 2021 and 2024, 164 faecal samples (80 from Croatia, 50 from Portugal, and 34 from Lithuania) were analysed using nested PCR targeting the cox1 gene. Twelve Sarcocystis species were detected: S. arieticanis, S. capracanis, S. capreolicanis, S. cruzi, S. gracilis, S. hjorti, S. iberica, S. linearis, S. miescheriana, S. morae, S. rossii, and S. tenella. The overall prevalence was highest in Croatia (78%) and Lithuania (62%) and lowest in Portugal (30%). Phylogenetic and haplotype analyses revealed high homogeneity and absence of geographic structuring. These results confirm the red fox as a key DH for multiple Sarcocystis species infecting European ungulates and underscore its epidemiological importance in parasite transmission across diverse ecosystems PB MDPI YR 2026 FD 2026 LK https://hdl.handle.net/20.500.14352/134086 UL https://hdl.handle.net/20.500.14352/134086 LA eng NO Gudiškis, N., Prakas, P., Beck, R., Figueiredo, A., Juozaitytė-Ngugu, E., Balčiauskas, L., Calero-Bernal, R., Gagović, E., Torres, R. T., Hipólito, D., Carmena, D., Stirkė, V., & Butkauskas, D. (2026). Molecular Evidence of the Role of the Red Fox (Vulpes vulpes) in the Epidemiology of Ungulate-Related Sarcocystis Species in Croatia, Lithuania, and Portugal. Animals, 16(4), 538. https://doi.org/10.3390/ani16040538 NO Author ContributionsConceptualization, N.G., P.P. and D.B.; methodology, N.G. and P.P.; formal analysis, N.G., R.B., A.F., E.J.-N. and D.C.; investigation, N.G., R.B., A.F., E.J.-N. and D.C.; resources, E.J.-N., R.C.-B., E.G., R.T.T., D.H. and V.S.; writing—original draft preparation, N.G., P.P., A.F., L.B., R.C.-B. and D.B.; writing—review and editing, N.G., P.P., R.B., A.F., E.J.-N., L.B., R.C.-B., E.G., R.T.T., D.H., D.C., V.S. and D.B.; supervision, N.G., P.P. and D.B.; funding acquisition, D.B. All authors have read and agreed to the published version of the manuscript. NO Research Council of Lithuania NO Fundação para a Ciência e a Tecnologia (Portugal) DS Docta Complutense RD 19 mar 2026