Habitat overlap and seroprevalence of toxoplasma gondii in wildlife and feral cats in a natural area

A 2 year cross-sectional study was conducted to evaluate the occurrence of feral and wild cats and the risk of Toxoplasma gondii infection in terrestrial wildlife in a natural area in Piatt County, Illinois. Cats are the definitive host for T. gondii and are a key component of rural and urban transmission of T. gondii to humans, livestock, pets, and wildlife. I selected 4 forest sites within the interior of the park and 4 edge sites within 300 m of human buildings. Feline and wildlife occurrence in the natural area was determined using scent stations, motion detection cameras, and overnight live trapping. Amount of cat habitat use was classified based on frequency of cat occurrence. Prevalence of T. gondii antibodies was determined using the indirect immunofluorescent antibody test (IFAT) and a positive titer of 1:25. Wildlife species were classified as having a large home range (LHR) or a small home range (SHR), based on published home range estimates and using a cutoff of 100 hectares. A total of 18 feral cats (16 at building and 2 at forest sites) were trapped with an overall seroprevalence of 33%; only one of the T. gondii positive cats was trapped in the forest. Feral cats were trapped 8 times more often at building sites (Ratio = 8; P = 0.083), and detected by scent stations 3 times more often at building sites compared to forest sites (Ratio = 3.2; P = 0.010). More LHR mammals were trapped at building versus forest sites (Ratio = 2.9; P < 0.001), while SHR mammals were trapped at similar abundances at building and forest sites. Sites with a higher frequency of cat occurrence, defined as ??? 9 cat occurrences across three detection methods, exhibited a higher T. gondii seroprevalence in SHR mammals (OR=4.2; P=0.018), although there was no significant difference when comparing seroprevalence at forest versus building sites in SHR or LHR mammals. Toxoplasma gondii antibodies were detected in wildlife at all sites and my findings point to the presence of feral cats as the source of environmental contamination. Although environmental contamination with oocysts of the parasite was not assessed, SHR mammals are good indicators of localized environmental contamination with oocysts at small spatial scales. Due to their greater spatial use and omnivorous diet, LHR mammals are good indicators of large spatial scale environmental contamination and intermediate host infection in a natural area. Multiple strategies to measure cat occurrence are important to evaluate risk for disease transmission compared to using live trapping of cats only, as feral cats in my study showed evidence of being trap shy, although they were detected in the park by other indirect methods. This study improves my understanding of ecological drivers behind spatial variation of T. gondii occurrence within a natural area