BABESIA I// 



(4) The club-shaped bodies pass from the gut of the tick into the ovary, and so 

 get into the ova. There they become globular, and later are found in the cells of 

 the developing tick-embryo. The parasites are, then, transmitted hereditarily. 

 Similar globular bodies are found in the tissue cells of the body of tick nymphs 

 which have taken up piroplasms. The globular stage was called the "zygote " by 

 Christophers, but it may correspond to the oocyst of Plasmodia. 



(5) The globular body divides into a number of "sporoblasts," which become 

 scattered through the tissues of the larval or nymphal tick, as the case may be. 



(6) The sporoblasts themselves divide into a large number of sporozoites, which 

 are small uninucleate bodies, somewhat resembling blood piroplasms. The sporo- 

 zoites collect in the salivary glands of the tick. They are inoculated into the 

 vertebrate when the tick next feeds. 



The chief species of Babesia and their pathogenic importance 

 may be listed thus : 



(1) Babesia bovis (Babes) produces infectious hsemoglobinuria 

 of cattle in Europe and North Africa. It is transmitted by Ixodes 

 rid n us. A similar parasite also occurs in deer. 



(2) Babesia bigcrniua (Smith and Kilborne) produces Texas 

 fever, tristeza, or red-water in cattle in North and South America, 

 South Africa and Australia. It is transmitted by Boophilns annulatiis 

 in North America, by B. auslralis in Australia, South America, and 

 the Philippines, and by B. decoloratns in South Africa. 



The parasite is from 2 //, to 4 //< long, and from 1-5 //, to 2 //, broad. 

 Babesia bigemina may be the same parasite as B. bovis. 



(3) Babesia divergens (MacFadyean and Stockman) is a small 

 parasite. It is found in cattle suffering from red-water in Norway, 

 Germany, Russia, Hungary, Ireland, Finland, and Fiance, and is 

 transmitted by Ixodes ricinns. 



(4) Babesia cauls (Piana and Galli-Valerio) gives rise to malignant 

 jaundice or infectious icterus in dogs in Southern Europe, India, and 

 other parts of Asia and North Africa, where it is transmitted by 

 Rhipicephalus sanguineus. In Africa generally, especially South 

 Africa, the disease is transmitted by Hcemaphysalis leaclii. Babesia 

 cams varies from 07 yu, to 5 //,, the size depending partly on the 

 number of parasites within the corpuscle. It averages about 3 //,. It 

 has been cultivated in Bass' medium (glucose and infected blood), 

 see p. 172. 



In India Piroplasma gibsoui (Patton) infects hunt dogs and jackals. 

 It is annular or oval in shape. 



(5) Babesia ovis (Babes) produces " Carceag," a disease of sheep 

 in Roumania, the Balkan Peninsula, Italy, and Transcaucasia. It 

 varies in size from i //, to 3 //,. It is transmitted by Rhipicephalus 

 bursa. The parasite has recently been recorded from Rhodesia. 



(6) Babesia caballi (Nuttall and Strickland) causes " biliary 

 fever" in equines. The parasite occurs in Russia, Roumania, and 



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