86 SWINE PLAGUE 



ous polar-stained swine-plague germs present. An agar culture from 

 heart's blood contained only swine-plague germs. 



"From the peritoneal exudate of pig, consisting of cells and fibrin 

 and numerous bacteria of several varieties, two agar plate cultures were 

 made. On Place A one large colony of spore-bearing bacilli and one 

 small colony of swine-plague germs. Plate B, completely overgrown 

 by the spore -bearing bacillus. 



"A bouillon culture from the exudate contains streptococci and 

 swine-plague bacteria. Agar plate cultures were made therefrom and 

 both germs isolated. 



"At the same time a large rabbit was inoculated subcutaneously 

 with a bit of the exudate. Dead in 18 hours. vStained cover-glass pre- 

 parations of blood from heart, spleen and liver tissue show polar- 

 stained swine-plague germs. An agar culture from the blood contains 

 only swine-plague germs. 



"From the spleen, after thoroughly scorching through the exudate, 

 two agar plate cultures and a bouillon culture were made with bits of 

 spleen pulp. The bouillon culture contained only swine-plague germs. 



"The swine-plague bacteria were thus obtained from lungs, pleura, 

 spleen, and peritoneal exudate, while hog-cholera bacilli, which were 

 looked for with the greatest care, could not be found." (Smith, 

 Report on Swine Plague, p. 62. ) 



The course of the disease varies in acute cases from one to 

 three weeks. In chronic or complicated cases it is indefinite. 



The prognosis in swine plague is very unfavorable. Most 

 of the affected animals die, and those that recover are usually 

 not thrifty. 



§ 72. Differential diagnosis. In sporadic cases, swine 

 plague is to be differentiated from broncho-pneumonia due to 

 other causes than the swine-plague bacterium. Pneumonia of 

 a non specific nature is often associated with deaths due to 

 dietary or other causes. It frequently causes death in chronic 

 cases of other diseases (terminal pneumonia). 



In epizootics or outbreaks, it is to be distinguished from 

 hog cholera when there is accompanying catarrhal pneumonia. 

 To make a positive diagnosis, it is usually necessary to depend 

 upon the results of the bacteriological examination. 



Pneumonia resulting from lung worms {Strongylus para- 

 doxus) can be distinguished by a careful examination of the 

 contents of the bronchioles. 



