Submitted to: Veterinary Parasitology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 15, 2005
Publication Date: February 20, 2005
Citation: Vianna, M.C., Sreekumar, C., Miska, K.B., Hill, D.E., Dubey, J.P. 2005. Isolation of Neospora caninum from naturally infected white-tailed deer (Odocoileus virginianus). Veterinary Parasitology. 129:253-257.
Interpretive Summary: Neospora caninum is a single-celled parasite of livestock. It is a major cause of abortion in dairy cattle worldwide. Domestic dogs are the only known reservoir hosts. Scientists at the Beltsville Agricultural Research Center have isolated N. caninum for the first time in white-tailed deer. These findings will be of interest to biologists, parasitologists and veterinarians.
Attempts were made to isolate Neospora caninum from naturally infected white-tailed deer (Odocoileus virginianus). A total of 110 deer killed during the 2003 hunting season in Virginia region were used for the isolation of N. caninum. Of these, brains from 28 deer that had NAT titer of ' 200 were inoculated into interferon-gamma gene knock out (KO) mice. N. caninum was isolated form the tissues of three deer and all three isolates were mildly virulent to KO mice. Only one of the isolates could be adapted to in vitro growth. Protozoa in the tissues of KO mice reacted with N. caninum-specific polyclonal antibodies and N. caninum DNA was demonstrated in infected tissues by PCR assays; sequences of portions of the ITS-1 and gene 5 loci were identical to those in the public database. This is the first record of isolation and propagation from white-tailed deer and lends credence to the existence of a sylvatic cycle of N. caninum involving large wild herbivores and canids.