Presence and Characterization of Zoonotic Bacterial Pathogens in Wild Boar Hunting Dogs () in Tuscany (Italy).

Domestic dogs () used for wild boar () hunting may represent incidental hosts for several zoonotic pathogens. This investigation aimed to evaluate the presence of anti- antibodies and the occurrence, antimicrobial resistance, and virulence of spp., , and in sera and rectal swabs collected from 42 domestic hunting dogs in the Tuscany region (Italy). Regarding , 31 out of 42 serum samples (73.8%) were positive and serogroup Pomona was the most detected (71.4%) at titers between 1:100 and 1:400. Four isolates (9.52%) were obtained, all belonging to serotype Infantis; two of them showed antimicrobial resistance to streptomycin, while and presence was assessed in all but one isolate. Concerning , seven isolates (16.7%) were obtained, six belonging to biotype 1 and one to biotype 4. Resistance to amoxicillin-clavulanic acid, cephalothin, and ampicillin was detected. Biotype 4 presented three of the virulence genes searched (, , ), while isolates of biotype 1 showed only one gene. No was isolated from dog rectal swabs. The results suggest that hunting dogs are exposed to different bacterial zoonotic agents, potentially linked to their work activity, and highlight the possible health risks for humans.