SPOROZOA 461 



Piroplasma canis 



Disease Produced. Biliary fever or malignant jaundice of the 

 dog. 



Pram and Galli-Valerio, in 1895, first described the blood 

 parasite of canine piroplasmosis. 



Distribution. It has been reported in China, Italy, France, 

 Hungary, South Africa,. East Africa, and possibly from the United 

 States. 



Morphology. The organisms are morphologically almost 

 identical with P. bigeminum. They are generally 2 to 4 n in diam- 

 eter. They are sometimes found abundantly in the plasma and 

 in a single cell there may be as many as sixteen of the organ- 

 isms. The free organisms are spherical; those within the cor- 

 puscles are pear-shaped or many angled. Multiplication is appar- 

 ently by direct division. 



Fig. 202. Piroplasma canis: 1-11, Organisms in various developmental 

 stages in red blood-cells in culture; 12, 13, organisms free in the plasm 

 (Deseler). 



Pathogenesis. The disease may be readily transferred by the 

 injection of virulent blood. It cannot be transmitted to other 

 species of animals. Nuttall and Graham Smith did not succeed 

 in reproducing the disease in the fox and jackal. The period of 

 incubation is three days or more. There is fever, and sometimes 

 icterus and hemoglobinuria. Anemia is marked. The spleen is 

 greatly enlarged, the gall-bladder is distended, and the kidneys 

 are often ecchymotic. Chronic cases frequently recover. The 

 acute cases are almost invariably fatal. Animals which have 

 apparently recovered retain the parasite in the blood for long 

 periods and retain their infect ivity. 



Bacteriological Diagnosis. Stained blood-films will demon- 

 strate the organism if present. 



