604 VETEEINAEY HYGIENE 



the Veterinary Department, Cape Colony. He uses a 

 simultaneous inoculation of virulent blood and serum as a 

 protective inoculation, or serum alone as a curative agent. 



EPIZOOTIC DISEASES DUE TO PYROPLASMOSES. 



Hcemo-albuminuria (Texas Fever) — East Coast Fever of 

 Cattle — Malarial Fever of Equines. 



In the chapter dealing with Bacteria, Dr. Theiler has 

 drawn attention to the important group of Protozoa; we 

 have now to consider certain diseases due to a member of 

 this family, viz., the Pyroplasma. 



These micro-organisms attack and live within the red 

 blood corpuscles. In the ox one variety produces Texas 

 Fever, another causes the devastating East Coast Fever or 

 Rhodesian Eed Water, which is at present such a serious 

 plague in South Africa. In the horse and dog a pyroplasma 

 produces epizootic malarial (biliary) fever, a distinct species 

 in each case being responsible for the disease. 



In all cases the affections are produced by the bite of a 

 tick, which carries the organism within its body obtained 

 from the blood of a pre-existing case, so that these diseases 

 can only exist where there are ticks to transmit the 

 affection. 



Some, like Texas Fever and Biliary Fever, can be com- 

 municated by the direct inoculation of the affected blood ; 

 others, like East Coast Fever, can only be communicated by 

 the bite of the tick, so that within the body of this parasite 

 some further elaboration of the organism occurs. 



In Australia ' tick fever,' as it is locally called, has been 

 responsible for very heavy losses. This disease does not 

 differ from Texas Fever, or what is known in Europe as 

 Hsemo-albuminuria or Red Water. 



The blood of animals which have recovered is infective 

 for a very long time, so that Red Water may be produced by 

 the inoculation of an animal with blood from one apparently 

 in perfect health. 



It was this fact that caused so much trouble in the serum 



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