Sporozoa in animals with particular reference toToxoplasmaandSarcocystis

Abstract

Extract Symptomatic and asymptomatic infections by Toxoplasma and Sarcocystis have been recognized for many years, but it has been only within the last few years that the life-cycles and natural means of perpetuation of some of these species have been worked out. The initial breakthrough resulted from the astute observation of Hutchison ( 1965 Hutchison, W. M. 1965. Experimental transmission of Toxoplasma gondii. Nature (Lond.), 206: 961–962. [Google Scholar] ) who demonstrated a resistant form of Toxoplasma in cat faeces. Hutchison and co-workers and other groups in the United States and elsewhere later demonstrated that Toxoplasma cysts on ingestion by susceptible cats went through a typical coccidial cyclein the epithelium of the small intestine. Following on these observations workers in Germany, followed by others in the U.S.A. and Australia, have demonstrated a similar intestinal cycle for several members of the genus Sarcocystis, in several species of meat-eating animals.