?74 



SWINE PRACTICE 



temperature of an ice box the virulence of the virus is retained for 

 many months. It is A^ery resistant to dilute solutions of phenol, cor- 

 rosive sublimate, and ehinosol. The length of time the virus may 

 remain virulent on infected premises has not yet been determined, 

 but it easily survives a single winter. Certain bacteria including 

 one spirochete may be factors in predisposing swine to the flltrable 

 virus. These various microbian agents are also responsible for com- 

 plications of hog cholera. 



Fig. 70. Hearts. A, showing acute inflammation of the auricle and 

 hyperemic areas in the ventricle, a common condition in hog 

 cholera; B, normal. 



The Bacillus suipestifer is no doubt a factor in the production of 

 secondary lesions and some of the complications of hog cholera. 



Bacillus suisepticus is frequently demonstrable in the carcasses of 

 swine that have died of hog cholera. This organism is the causative 

 agent of swine plague, and will receive proper consideration in the 

 discussion of that disease. Suffice to say, it is frequently an as- 



