Neospora caninum exposure in Wisconsin wildlife

Abstract

ABSTRACT NEOSPORA CANINUM EXPOSURE IN WISCONSIN WILDLIFE

By Todd C. Anderson

The parasitic protozoan Neospora caninum is a major cause of abortion in cattle worldwide. Transmission occurs by fecal-oral contamination from infected dog feces or by congenital route in infected cattle. Wolves, coyotes, cattle, and deer have been implicated in transmission, but the host range of the parasite is still poorly defined. Many studies have demonstrated seroprevalence within a single mammalian species in an area, but few have examined the interaction of different potential host species in the same geographical area. To further define the host range of the parasite and to characterize the sylvatic wildlife transmission cycle, we determined seroprevalence and molecular prevalence of N. caninum in several central Wisconsin wildlife species. Western blot analysis was used to demonstrate the presence of circulating antibodies against N. caninum. Seroprevalence in wildlife species varied from 19.0% in white-tailed deer, 14.7% in coyotes, 11.1% in foxes to 0% in raccoons and opossums. PCR specific for the Nc5 locus of N. caninum was performed on brain tissue of 54 raccoons and 53 opossums, however no positive samples were found. Fecal analysis was then performed in an effort to find N. caninum and to characterize the intestinal parasite loads of wildlife species. Although the fecal analysis revealed no active shedding of N. caninum oocysts, several other parasite species were found in the samples. This study suggests that parasite life cycle is occurring in Wisconsin between coyote and deer.