Submitted to: Veterinary Parasitology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 6/3/2004
Publication Date: 7/15/2004
Citation: Rodrigues, A.R., Gennari, S.M., Aguiar, D.M., Sreekumar, C., Hill, D.E., Miska, K.B., Vianna, M.C., Dubey, J.P. 2004. Shedding of Neospora caninum oocysts by dogs fed tissues from naturaly infected water buffaloes (Bubalus bubalis) from Brazil. Veterinary Parasitology. 124:139-150. Interpretive Summary: Neospora caninum is a single celled parasite that causes abaortion in cattle worldwide. The dog is the main reservoir host. Sccientists at the Beltsville Agricultural Research Center and the University of Sao Paulo Brazil report isolation of Neospora caninum from 7 water buffaloes from Brazil for the first time. These results will be of interest to biologists, parasitologists and veterinarians.
Technical Abstract: Attempts were made to isolate Neospora caninum from naturally infected water buffaloes (Bubalus bubalis) from Brazil. Brains from six buffaloes with indirect fluorescent antibodies (>1: 100) to N. caninum were used to isolate the parasite by bioassay in dogs and gerbils followed by in vitro culture. Shedding of Neospora-like oocysts was noticed in dogs fed brains from three buffaloes (isolate designation NcBrBuf-1, 2 and 4). Two more isolates (NcBrBuf-3 and 5) were obtained by in vitro culture of the brains of gerbils previously infected with brains of two other buffaloes. The identity of the isolates was confirmed by biological and molecular methods. The isolates were found to be non-pathogenic to gerbils. All five isolates amplified the gene 5 amplicons using Neospora-specific PCR assay. The sequences of gene 5 fragments and the common toxoplasmatiid ITS-1 fragments were analysed. The dynamics of oocyst production in the dogs indicate that water buffaloes are natural intermediate hosts for N. caninum. This is the first report of isolation of N. caninum from water buffaloes.