ARS | Publication request: Gray wolf (Canis lupus) is a natural definitive host for Neospora caninum

Submitted to: Veterinary Parasitology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 11, 2011
Publication Date: May 20, 2011
Citation: Dubey, J.P., Jenkins, M.C., Chellaiah, R., Miska, K.B., Ferreira, L., Martins, J., Kwok, O.C., Choudhary, S. 2011. Gray wolf (Canis lupus) is a natural definitive host for Neospora caninum. Veterinary Parasitology. 181:382-387.

Interpretive Summary: Neospora caninum is a single-celled parasite, very closely related to Toxoplasma gondii. It causes abortion in cattle and paralysis in companion animals. It is the most important cause of abortion in dairy cattle. Dogs and coyotes are its definitive hosts and main reservoirs of infection. This parasite is transmitted efficiently from the cow to the calf transplacentally. In the present papers the authors present evidence that the gray wolf is new definitive host for N. caninum. The results will be of interest to biologists, parasitologists, and veterinarians.

Technical Abstract: The gray wolf (Canis lupus) was found to be a new natural definitive host for Neospora caninum. This finding is based on the recovery of Neospora-like oocysts from the feces of 3 of 73 wolves from Minnesota examined at necropsy, and on successful amplification of N. caninum-specific sequences from the oocysts DNA. Oocysts from one wolf were infective for the gamma interferon gene knock out (KO) mice. Viable N. caninum (designated NcWolfUS1) was isolated in cell cultures seeded with tissue homogenate from the infected mouse. Typical thick walled tissue cysts were found in outbred mice inoculated with the parasite from the KO mouse. Tissue stages in mice stained positively with N. caninum-specific polyclonal antibodies. Our observation suggests that wolves are probably the missing link in the sylvatic cycyle of N. caninum.