354 DR. LEGEAR'S STOCK BOOK. 



particularly if cheese-like masses are found in those organs, the 

 disease is probably swine plague. 



Small blood spots in the tissues or scattered over the intern;)! 

 organs indicate hog cholera, while inflammation of the sorous 

 membranes indicates swine plague. 



The germs of hog cholera collect or grow in clumps in the 

 blood vessels, which leads to a plugging of the smaller ones, with 

 frequent rupture and escape of blood. This causes red spots to 

 form where the blood leaves the vessels and collects in the solid 

 tissues. In swine plague the bacteria are evenly diffused through 

 the blood, never form plugs, and, therefore, bleeding from this 

 cause is not seen. 



In hog cholera the first effect of the disease is believed to be 

 upon the bowels, with secondary invasion of the lungs; in swine 

 plague it is the reverse of this. 



Notwithstanding the difference in typical cases of the two dis- 

 eases, there are many outbreaks where it is impossible to distin- 

 guish betwen them, as both diseases may be affecting the same 

 animal at the same time, or the changes may somewhat resemble 

 both diseases. In such cases a diagnosis can be made only by 

 microscopic examination and cultivation of the germs. 



Prognosis. The result of an outbreak of this malady is im- 

 portant to know, but difficult to state, as the losses will depend 

 partly upon the susceptibility of the hogs to the disease and 

 partly to the virulence of the contagion in the particular out- 

 break. If the animals are very susceptible and the conta. ion very 

 virulent, the loss even in large herds may reach 90 to ( .)~>. or even 

 100 per cent in those cases where the disease is allowed to run its 

 course. In milder outbreaks, or with the animals more capable of 

 resisting the contagion, the losses vary from 20 to 60 per cent. 

 More animals recover toward the end of an outbreak than at the 

 beginning. A portion of those recovering will fatten, but others 



