Emerging Host, Emerging Parasites: Cardiopulmonary Nematodes in Italian Golden Jackals (Canis aureus)

Cardiopulmonary nematodes of canids are parasites of increasing veterinary relevance, capable of infecting a wide range of wild and domestic species and causing severe disease. Climate change, vector ecology, and wildlife dynamics have contributed to their geographic expansion across Europe. Wild canids, including golden jackals (Canis aureus), may serve as reservoirs and bridge hosts, sustaining environmental contamination and facilitating parasite dispersal. The jackal's range expansion in Italy increases contact likelihood with infective forms, underscoring the need for surveillance. A total of 109 jackals collected from Northeastern Italy (Friuli Venezia Giulia) between 2009 and 2025 were analysed. Necropsy was performed and lesions were recorded. Nematodes were identified morphometrically and via PCR (mtCOI, 18S rRNA, 12S rRNA genes). Spatial modeling (generalized linear models) was applied to assess the influence of environmental and anthropogenic variables on infections. Overall, 52 jackals (47.7%) were positive for at least one parasite species: Angiostrongylus vasorum showed the highest prevalence (34.9%), followed by Eucoleus aerophilus (13.8%), Crenosoma vulpis (12.8%), and Dirofilaria immitis (4.6%). Host sex significantly influenced the prevalence and abundance of C. vulpis (higher in males). Mean yearly precipitation and coverage of agricultural areas were statistically significant and positively associated with A. vasorum and E. aerophilus infections. Our findings demonstrate that the distribution of these parasites is significantly shaped by environmental and anthropogenic drivers. As jackals increasingly exploit fragmented, human-dominated habitats, their role at the wildlife–domestic interface becomes more critical, potentially increasing the risk of parasite spillover. The documentation of multiple co-infections and the presence of zoonotic helminths (D. immitis and E. aerophilus) underscore the importance of this canid in the environmental maintenance of these nematodes. Given the ongoing westward expansion of jackals across Europe, integrated One Health surveillance programs are essential to monitor the dispersal of these pathogens in multispecies landscapes.