Submitted to: Journal of Parasitology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/5/2003
Publication Date: 8/12/2003
Citation: Yantis, D., Moeller, R., Braun, R., Gardiner, C., Aguirre, A., Dubey, J.P. 2003. Hepatitis associated with a sarcocystis canis-like protozoan in a hawaiian monk seal (monachus schauinslandi). Journal of Parasitology. 89:1258-1260. Interpretive Summary: Sarcocystis canis is a single-celled parasite of animals. It causes fatal hepatitis (liver disease) in many species of animals. Hawaiian monk seals are endangered in U.S. Waters. Scientists at Beltsville Agricultural Research Center and the AFIP, Washington D.C. report fatal hepatitis in a Hawaiian monk seal. These findings will be of interest to biologists, parasitologists, and pathologists.
Technical Abstract: A Hawaiian monk seal (Monachus schauinslandi) died in captivity at the National Marine Fisheries Service, Kewalo Basin Facility in Honolulu, Hawaii. The animal was icteric and the liver was friable. Microscopic lesions were detected in the colon and liver. Colonic lesions included multifocal, necrohemorrhagic colitis associated with gram-negative bacilli. The liver lesions included random hepatic necrosis and cholestasis. Asexual stages of a Sarcocystis canis- like apicomplexan were detected in hepatocytes. The parasite divided by endopolygeny. Merozoites occasionally formed rosettes around a central residual body. Ultrastructurally, merozoites lacked rhoptries. This is the first report of S. canis infection in M.schauinslandi, which is an endangered pinniped in U.S. waters.