SARCOCYSTIS, TOXOPLASMA AND RELATED PROTOZOA 



337 



taneously; the two drugs act synergistic- 

 ally (Eyles, 1956). 



For treatment of human ocular toxo- 

 plasmosis, Remington, Jacobs and Kauf- 

 man (1960) recommended that the patients 

 receive 2 oral loading doses of 200 mg 

 pyrimethamine and 2 g triple sulfonamides 

 each on the first day of therapy, and that 

 thereafter they be given 25 mg pyrimeth- 

 amine and 2 g triple sulfonamides twice a 

 day for 5 weeks. 



Prevention and Control : In the ab- 

 sence of solid information regarding the 

 mode of spread of toxoplasmosis, specific 

 preventive measures cannot be recom- 

 mended. The measures customarily em- 

 ployed to control infectious diseases 

 should be used. In addition, since many 

 wild mammals are apparently reservoir 

 hosts, contact with them should be avoided 

 and rodents should be controlled. Man and 

 his domestic animals apparently receive 

 their infections from the same source, but 

 it is not clear whether they can give it to 

 each other. 



Genus BESNOITIA Henry, 1913 



In this genus the pseudocysts are 

 found in the subcutaneous and connective 

 tissues, serosal membranes and else- 

 where. They have a heavy wall containing 

 nuclei, and are not divided into compart- 

 ments. A synonym of this name is Fibro- 

 cystis Hadwen, 1922. The name Globid- 

 iiim has often been used instead oi Besnoitia 

 for members of this genus, but this is in- 

 correct, since Globidium is a synonym of 

 Eimeria. 



The "cyst" wall is said by Pols (1954a) 

 to be formed entirely by the host, so that 

 it is actually a pseudocyst. The wall is 

 composed of a thin inner layer containing 

 a number of flattened, giant nuclei and a 

 thick, homogeneous or concentrically 

 laminated, eosinophilic outer wall. It is 

 positive to the periodic acid-Schiff test, 

 and the reaction is not affected by salivary 

 digestion (Frenkel, 1956). 



The trophozoites are banana-shaped, 

 crescentic or elongate oval, and slightly 



pointed at one end. They move by body 

 flexion. They reproduce by binary fission 

 or endodyogeny; multiple fission has also 

 been described. 



This genus is poorly known and has 

 often been confused with Ei)iieria and Sar- 

 cocystis. Species have been found in cat- 

 tle, horses, reindeer, caribou, rodents 

 and opossums. A somewhat similar or- 

 ganism described by Campbell (1954) as 

 the cause of Bangkok hemorrhagic disease 

 of chickens in Thailand is more probably 

 a fungus. 



BESNOITIA BESNOITI 

 (MAROTEL, 1912) HENRY, 1913 



Synonyms : Sarcocystis besnoiti, 

 Gastrocystis robini, Gastrocystis besnoiti, 

 Globidium besnoiti. The nomenclature of 

 this species has been discussed by Jelli- 

 son (1956). 



Disease : Besnoitiosis, olifantvel. 



Hosts : Cattle. Pols (1954) infected 

 the domestic rabbit experimentally. 



Location : The cysts are in the cutis, 

 subcutis, connective tissue, fascia, ser- 

 osae, mucosae of the nose, larynx and 

 trachea, and other places. Trophozoites 

 are in the blood, either extracellularly or 

 in monocytes, and in smears of lymph 

 nodes, lungs, testes, etc. 



Geographic Distribution : Europe 

 (southern France, Pyrenees, Portugal), 

 Africa (South Africa, Belgian Congo, 

 Angola, Sudan). 



Prevalence : According to Hofmeyr 

 (1945), B. besnoiti is endemic in South 

 Africa thruout the whole of the Bushveld 

 area from the Western Transvaal to 

 Potgietersrust district and probably fur- 

 ther north. He'rin (1952) found it in about 

 2% of the cattle he examined in Ruanda- 

 Urundi, Belgian Congo. Leitao (1949) 

 discussed its occurrence in Portugal. 



Morphology : The pseudocysts are 

 more or less spherical, without septa, 

 and about 100 to 500 (i in diameter. The 



