Diseases of Hogs. 155- 



ering the body with quick-lime. Carcasses should never 

 be thrown intd streams or left uncovered to decompose. 

 The pens and yards should be thoroughly cleaned and 

 well sprinkled with quick lime. The litter and manure 

 should be burned. After a lapse of several months the 

 pens should be whitewashed. The organism does not 

 form spores, hence is easily killed. 



Vaccination and serum treatment. For many years 

 efforts have been made to discover a vaccine that would 

 protect from hog cholera as the black leg vaccine pro- 

 tects against that disease, but the efforts have met with 

 little success. Eecently methods have been devised that 

 seem to promise success in preventing the spread of the 

 disease. A hog that has recovered from an attack of hog 

 cholera is immune to further attacks. If this immune 

 animal is inoculated with the blood of animal that has 

 the disease, the amount of protective substance in the 

 blood of the immune animal will be greatly increased, 

 so much so, that if some of its blood serum is transferred 

 to a second animal, it will be protected against a natural 

 attack of the disease for about a month. This method of 

 prevention is similar to the use of antitoxin in lockjaw. 

 If it is desired to make the protection more permanent, 

 a small amount of blood from a diseased hog is injected 

 into the animal at the same time the serum is adminis- 

 tered. In this case the protection lasts for a long time, 

 possibly during the life of the animal. Many difficulties 

 are encountered in the use of the serum treatment in a 

 practical way. It is to be hoped that these may be over- 

 come and the method made a real success. The treat- 

 ment can only be administered by a trained veterinarian, 

 especially is this true when the virulent blood is used to- 

 gether with the serum. 



