RESUMO
A serological survey was conducted in the Patagonia region of Argentina to estimate the prevalence of nine disease agents within the populations of free-ranging culpeo (Dusicyon culpaeus) and grey (Dusicyon griseus) foxes. The disease agents were Aujeszky's disease virus (ADV), Brucella, canine adenovirus (CAV), canine distemper virus (CDV), canine parvovirus (CPV), Encephalitozoon cuniculi, Leptospira, Neospora caninum, and Toxoplasma gondii. A total of 84 foxes were sampled (28 culpeo and 56 grey), and 73% of the sera had antibodies against one or more pathogens. Among these seropositive sera, 47% of them reacted to only one antigen, while the other 53% reacted to multiple antigens. The presence of antibodies to Toxoplasma (20%), Neospora (44%), Leptospira (30%) and Brucella (18%) suggests that these organisms actively circulate in the area. Antibodies against CDV, CAV and CPV were detected in 2%, 5% and 5% of foxes, respectively. Regarding Encephalitozoon cuniculi and ADV, no evidence of either was found.