Group VI. 

 INFECTIOUS DISEASES PRODUCED BY PROTOZOA. 



1. Piroplasmoses. 



{Babesioses, Malaria of Auimals.) 



To the group of piroplasmoses belong those diseases which 

 sometimes show an acute, at other times a chronic course and 

 are caused by a unicellular protozoa, the so called piroplasma 

 (pirosoma, babesia). The parasites are inoculated into the 

 body fluids of mammals by ticks, and in penetrating the red 

 blood corpuscles they produce their destruction, causing anemia, 

 and frequently also hemoglobinuria, as well as icterus to de- 

 velop in the animals. 



General Morphology and Biology of the Causative Factors. 

 Piroplasmas are unpigmented, roundish, pear, ring or rod- 

 shaped protozoa with a nucleus which probably encloses a 

 blepharoplast (centrosom), and are closely related to the 



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Fig. 128. Piroplasma higeminum : Typical rinn' and pear shapes. Tlie upper 

 row stained witli alkaline methylene liliie, the lower after Roniano\vsk\ . (After 

 Kossel & Weber). 



liemosporidia. In the inside of the red blood corpuscles, where 

 they are usually found, they are fre(iuently present in pairs, 

 in which the pear shapes meet each other with their pointed 

 ends. In the fresh condition they show ameboid movements. 



Their reproduction has, up to the present time, not been 

 accurately investigated. In the blood of the host it results 

 probably by the way of direct fission, or schizogony, in which 



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