Copromicroscopic and molecular survey of major endoparasites in wild boars (Sus scrofa) hunted in northern Italy

The wild boar population has been expanding worldwide, including in highly anthropized areas, increasing the likelihood of contact among wildlife, pets, livestock, and humans. Given the limited recent data on endoparasites circulating in Italian wild boars, this study aimed to determine their occurrence, prevalence, and fecal shedding in individuals hunted in northern Italy and to explore potential host-related risk factors. A total of 191 fecal samples were collected within the regional wildlife surveillance program in Lombardy and analyzed using the FLOTAC® dual technique with two flotation solutions (NaCl, specific gravity [s.g.] = 1.200; ZnSO₄, s.g. = 1.350). Coccidian oocysts were sporulated in 2.5% potassium dichromate for species identification, Balantioides coli was detected by sedimentation, and larvae from strongylid-type eggs were characterized morphologically and molecularly. Statistical analysis was performed using univariate and multivariate logistic regression models. Overall, 90.1% of wild boars tested positive for at least one parasitic taxon. The most prevalent protozoa were coccidia (60.7%) and B. coli (38.7%), while Metastrongylus spp. (44.0%) and other strongylid nematodes (37.2%) were the most frequent helminths. Seven Eimeria species and Cystoisospora suis were identified; E. polita was the most common, occurring in 70.7% of coccidia-positive samples. Molecular analyses also confirmed Globocephalus urosubulatus among strongylid-type larvae. Univariate analysis revealed a significantly lower prevalence of Ascaris sp. and B. coli in adult wild boars, although no significant associations were confirmed in the multivariate model. These findings indicate a high prevalence of endoparasites in the surveyed wild boar population from northern Italy and support their potential role as reservoirs of zoonotic agents. Continuous surveillance is essential to improve understanding of parasite ecology and mitigate transmission risks at the wildlife–livestock–human interface.