Sarcocystis cafferi, n. sp. (Protozoa: Apicomplexa) from the African buffalo (Syncerus caffer)

Authors: Dubey, Jitender; LANE, E - National Zoological Gardens Of South Africa; VANWILPE, E - University Of Pretoria; SULEMAN, E - National Zoological Gardens Of South Africa; REININGHAUS, B - US Department Of Agriculture (USDA); VERMA, SHIV - Non ARS Employee; Rosenthal, Benjamin

Submitted to: Journal of Parasitology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/15/2014
Publication Date: 12/1/2014
Publication URL: http://dx.doi.org/10.1645/13-467.1
Citation: Dubey, J.P., Lane, E., Vanwilpe, E., Suleman, E., Reininghaus, B., Verma, S., Rosenthal, B.M. 2014. Sarcocystis cafferi, n. sp. (Protozoa: Apicomplexa) from the African buffalo (Syncerus caffer). Journal of Parasitology. 100(6):817-827.

Interpretive Summary: Protecting food safety requires a comprehensive understanding of the suite of parasites that do cause disease, or only merely resemble, zoonotic pathogens. Cattle (Bos taurus) are hosts to several species of parasites in the genus Sarcocystis, one of which compromises food safety when infected beef is insufficiently cooked. Careful examination of physical, genetic, and phenotypic properties was required to distinguish this harmful parasite from others in cattle that pose no human health threat. These, in turn, resemble parasites in water buffalos (Bubalus bubalis), which are an important source of milk and meat, in their native India and China, most especially. Confusion remains, however, about the relationship of these parasites to those occurring in the African Cape Buffalo (Syncerus caffer), a distinct bovid native to Africa. Here, we describe a new species of parasite, provide a careful accounting of its unique morphological features, and identify and unexpectedly close genetic relationship between it and a parasite described from Asian water buffalo. The zoonotic potential of this new species is undoubtedly low, given that this host is hunted only infrequently as a trophy. However, the broader understanding of the parasites in bovines will be of interest to parasitologists, epidemiologists, and wildlife disease experts.

Technical Abstract: Four species of Sarcocystis are currently recognized in the Asian water buffalo (Bubalus bubalis): Sarcocystis fusiformis with macrocysts and cats as definitive hosts, S. buffalonis also with macrocysts and cats as definitive hosts, S. levinei with microcysts and dogs as definitive hosts, and S. dubeyi with microcysts and unknown definitive host. Sarcocystis infections have been reported also from the African buffalo (Syncerus caffer) but the species have not been named. Here we propose a new name Sarcocystis cafferi from the African buffalo. Based on histological examination of sections from muscles of 92 buffalos from the Greater Kruger National Park, Pretoria, South Africa, and review of literature only 1 species of Sarcocystis was found in the African buffalo. These sarcocysts were macroscopic (up to 12 mm long and 6 mm wide) and were located in the neck muscles and overlying connective tissue. They were pale yellow in color, and shaped like a litchi fruit stone or cashew nut and were turgid or flaccid oval to round (not fusiform). Ultrastructurally, the sarcocyst wall was up to 3.6 µm thick and had highly branched villar protrusions that were up to 3 µm long. The villar projections contained filamentous tubular structures, most of which were parallel to the long axis of the projections but some tubules criss-crossed, especially at the base; granules were absent from these tubules. Longitudinally cut bradyzoites were 12.1x 2.7 µm in size. A distinctive feature was the presence of a long convoluted mitrochondria, and no more than 2 rhoptries. Sarcocystis cafferi sarcocysts were distinguished from S. fusiformis morphologically.