Prevalence of Toxoplasma gondii and Neospora caninum in red foxes in Slovakia

Sera or meat juices of 177 red foxes (Vulpes vulpes) originated from the localities of a human-influenced landscape (Group 1) and 126 foxes from the protected mountain region (Group 2) of Slovakia, collected during 2010–2014 were tested for the presence of antibodies against Toxoplasma gondii using indirect ELISA and Neospora caninum by competitive ELISA. The tissue and uncoagulated blood samples were examined for the presence of the parasite’s DNA. The total seropositivity to T. gondii was 62.7% (190/303) and to N. caninum 26.4% (80/303). In the Group 1 antibodies to T. gondii were detected in 74.0% (131/177) and to N. caninum in 38.9% (69/177). In the Group 2 significantly lower seropositivity of 46.8% (59/126) to T. gondii antigens (P = 0.0218) and 8.7% (11/126) to N. caninum (P = 0.0001) was detected, respectively. However, by using molecular method, the presence of both parasites, was recorded less frequently. While in Group 1 T. gondii DNA was detected in 10.0% and N. caninum DNA in 18.3% of examined samples, in Group 2 T. gondii DNA was not detected at all and N. caninum was detected in 9.1% samples only. Results indicate that examined infections are highly common in the red foxes in Slovakia and are widespread in the locations of Eastern Slovakia bordering Poland, Ukraine and Hungary. The high infection rate in foxes representing reservoir hosts, presumably originates from their infected prey, ungulate carcasses, or from residual infected tissues in the hunting grounds after evisceration of shot animals during a hunting season.