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BLACKLEG AND VACCINATION libr 



BOTA 



Drs. N. S. Mayo and W. W. Diraock 



Chief and first Assistant. 

 Department of Animal Industry. 



Blackleg is a cointnon disease of calves and young cattle 

 i n Cuba and causes heavy losses to cattle growers annually. 

 ít is thought by raany cattlemen that blackleg has been 

 imported to Cuba since the war of 1895. Blackleg is coinmon 

 in the United States of America and Europe. 



In English this disease is commonly called "blackleg" 

 or "blackquarter" because is usually aífects a leg or quarter 

 and the diseased meat or muscle is dark in color. In French 

 it is called "Charbon symptomatique" in Germán "Rausch- 

 brand" and in Spanish "Carbúnculo symptomatico". 



Blackleg is a transmissable disease produced by a specific 

 germ, Bacilhts Chauvaei. This is a rod shaped organism 

 with rounded ends. It forms spores, small round seed like 

 bodies within the bacillus, sometimes in the center of the 

 rod shaped bacillus, but frequently toward the end, this 

 gives the rod a club shaped appearance. The bacillus of 

 blackleg forms spores within and also outside of the animal 

 body. The spores may be called a seed form of the germ and 

 are more resistent to injurious influences than are the germs. 

 The accompanying illustration was drawn from a specimen 

 of diseased tissue taken from a calf suffering from blackleg. 

 The round cells are the red corpuscles of the blood while the 

 stick like bodies are the germs of blackleg. The illustration 

 is magnified more than 2,000 times. The germs of blackleg 



