SARCOCYSTIS, TOXOPLASNM AND RELATED PROTOZOA 



32S 



to bring infected birds which they have 

 shot to a diagnostic laboratory to learn 

 whether they are safe to eat. 



Morphology : The cysts are several 

 millimeters long and are compartmented. 

 The cyst wall is smooth. The trophozoites 

 measure about 8 by 2 jii . 



FAMILY TOXOPLASMATIDAE 



Members of this family form pseudo- 

 cysts, i.e. , the "cyst" wall is formed by 

 the host and not by the parasite. A true 

 cyst may be formed as well (cf. Lainson, 

 1958). Multiplication is by binary fission 

 or endodyogeny, and possibly by schizo- 

 gony in the young pseudocysts. 



This family includes the genera 

 Toxoplasma, Besnoitia and Enceplialito- 

 zoon. Its taxonomy has been reviewed 

 by Westphal (1954), Van Thiel (1956), 

 Biocca (1949, 1957), and Goldman, Carver 

 and Sulzer (1958), among others. 



Genus TOXOPLASMA 

 Nicolle and Manceaux, 1908 



In this genus the pseudocyst wall is 

 thin. A single, euryxenous species, T. 

 gondii is recognized. 



Because of its importance as a cause 

 of human disease, T. gondii has been 

 studied intensively and the literature on it 

 is vast. Eyles and Frenkel (1952) pub- 

 lished a bibliography which listed 920 

 papers and then supplemented it (1954) 

 with 400 more. A great many more papers 

 have been published since that time. It is 

 obviously impractical to attempt to refer 

 to them all here. Various aspects of 

 Toxoplasma and toxoplasmosis have been 

 reviewed by Weinman (1952), Habegger 

 (1953), Jacobs (1956, 1957), Feldman and 

 Miller (1956), Siim (1956), Eichenwald 

 (1956), Frenkel (1956a), Hoare (1956), 

 Eyles (1956), de Roever-Bonnet (1957) 

 and Siim (1960). 



TOXOPLASMA GONDII 

 NICOLLE AND MANCEAUX, 1908 



Synonyms : Toxoplasma cuniculi, T. 

 caviae, T. canis, T. musculi, T. ratti, 

 T. laidlawi, T. sciuri, T. pyrogenes, 

 T. hominis. 



Disease : Toxoplasmosis, 



Hosts : T. gondii was first found in 

 the gondi {Ctenodactylus gondi), a North 

 African rodent, but it has since been found 

 in many species of mammals and birds. 

 Its host list includes the gondi, house 

 mouse, Norway, black, climbing and 

 water rats, squirrel, ground squirrel, 

 vole, guinea pig, chinchilla, marmot, the 

 Chilean rodent, Octodon degus, the Uru- 

 guayan rodent, Ctenomys torquatus, 

 rabbit, hare, mole, shrew, hedgehog, dog, 

 cat, fox, weasel, ferret, mink, wombat, 

 bandicoot, brush-tail possum, marsupial 

 rat, pig, sheep, ox, baboon, chimpanzee, 

 macaque {Macaca tantala), whiteface mon- 

 key {Cebits capucinus), cotton-topped mar- 

 moset (Oedipomidas oedipus), squirrel 

 monkey {Saimiri sciiirea), man, pigeon, 

 chicken, crow, canary, penguin and par- 

 tridge {Perdrix perdrix) (Ratcliffe and 

 Worth, 1951; Christen and Thiermann, 

 1953; Talice, Perez-Mor^ra and Mossera, 

 1954; Jacobs, 1956; Finlay and Manwell, 

 1956; Van den Akker, Bool and Spitseshuis, 

 1959; Cook and Pope, 1959; Benirschke and 

 Richart, 1960). In addition, organisms 

 which resemble Toxoplasma morpholog- 

 ically have been seen in reptiles; and 

 turtles, lizards, geckos and chameleons 

 can be infected experimentally (Jacobs, 

 1956). On the other hand, most of the 

 organisms reported as Toxoplasma from 

 the blood of -various wild birds are prob- 

 ably Lankesterella. 



Location : Toxoplasma is an intra- 

 cellular parasite of many types of cells, 

 including neurons, microglia, endothel- 

 ium, reticulum, liver parenchyma cells, 

 lung and glandular epithelial cells, car- 

 diac and skeletal muscle cells, fetal 

 membranes and leucocytes. In acute in- 

 fections, the parasites may be found free 

 in the blood and peritoneal exudate. 



