Serosurvey of antibodies against Toxoplasma gondii and Neospora caninum in white-tailed deer from Northern Mexico

The objective of this study was to determine the seroprevalence of Toxoplasma gondii and Neospora caninum in white-tailed deer from Northern Mexico. Sera from 532 white-tailed deer (Odocoileus virginianus) from three Northern states of Mexico were assayed for antibodies to T. gondii by ELISA and western blot. From these samples, 368 were available to test for N. caninum antibodies by ELISA. The overall prevalence for T. gondii antibodies was 13.9% (74/532; CI₉₅ 11-17) and for N. caninum 8.4% (31/368; CI₉₅ 6-12). There was a significant association between positive ELISA results for T. gondii, with management factors within ranches, such number of deer per hectare and geographic location of deer, but none for N. caninum. T. gondii infection in the deer from Guerrero, Coahuila had an increased risk than those from Nuevo Laredo, Tamaulipas (OR, 8.3; CI₉₅ 1.9-35.4; P<0.05) and ranches with one deer in 15ha had increased risk of positive association (OR, 2.61; CI₉₅ 1.5-4.4; P<0.05). These findings may have environmental or public health implications because venison can be an important meat source of T. gondii infections for humans and feral cats.