9 



four calves in every hundred, and if we assume that of the 

 370,486 doses sent out 300,000 were used it would mean a 

 saving of 12,000 calves, which at thelowprice of $10.00 each 

 represents a saving to the cattle growers of $120,000 in fonr- 

 teen months. 



DISTRIBUTION. 



Blackleg seems to be generally distributed in Cuba as 

 the following data also furnished by the Junta Superior de 

 Sanidad showing the distribution of the vaccine in the 

 different provinces of the Island during the fourteen months 

 already referred to. 



Pinar del Río 24,225 



Habana 37^7 5 



Matanzas 46,818 



Santa Clara : I24,47 5 



Camagüey 81,620 



Oriente 55>45Q 



Total 370,463 



European veterinary writers generally state that in con- 

 tinental Europe, blackleg occurs most frequently in low wet 

 lands, but this is not true so far as we have been able 

 to judge either in the central United States or in Cuba. 

 Blackleg seems to be as common on the high hilly pastures 

 as in the lowlands, and according to the Cuban statistics 

 before quoted the heaviest losses occur in the dry season, 

 December and January. 



IMMUNITY. 



Immunity is the power possessed by an animal that 

 enables it to resist disease. Calves between the ages of three 

 and twenty months possess but little immunity against black- 

 leg. Afier twenty months, immunity increases rapidly with 

 age and it is rare that an animal 30 months or over will 

 contract blackleg. A few calves possess a natural immunity 

 against blackleg and they do not contract the disease when 



