198 LIVESTOCK ON THE FARM 



may be followed by scours with an offensive odor to the dis- 

 charge. They will also be inclined to crawl into the straw. 

 When driven out they appear weak and sometimes walk with 

 a wobbly gait. The skin on the tenderer parts of the body 

 may also be red in spots or speckled inclining more to complete 

 redness. 



To make sure, however, whether a hog has cholera, in order 

 to protect the rest of the herd, a postmortem examination 

 should be made. 



The sick animal, after slaughtering, should be laid on its 

 back and cut open as for dressing. The head should be partly 

 cut off just back of the jaw bones. By cutting in here some 

 glands about the size of hickory nuts are found. In a healthy 

 hog these are of a light flesh color but in a hog afflicted with 

 cholera they are enlarged and inflamed. In a cholera hog 

 there may also be well-defined red areas in the lungs. The 

 interior of the body may also be red speckled, and the mem- 

 brane surrounding the kidneys, cut on one side and peeled 

 off, may show the kidneys speckled with fine red spots. Some- 

 times they are badly speckled like a turkey egg and some- 

 times there are only a few red spots. These may also be very 

 fine. The enlarged and inflamed glands in the neck, the 

 reddened areas in the lungs and the speckled kidneys are, as 

 far as known at present, a sure indication of hog cholera. 



When the disease starts in a herd the sick ones should at 

 once be entirely isolated. The well hogs should at once be 

 treated with the hog cholera serum. This can be had from a 

 State institution or from commercial manufacturing com- 

 panies. The State livestock sanitary board should be con- 

 sulted, if there is one. As serum is only a preventive it need 

 not be used on the sick hogs. 



There are two methods of vaccination, the "serum only" 

 method and the "double treatment." By the former the hogs 

 are treated with serum alone. Serum is the blood from a hog 

 that is immune from cholera and then has been treated with 

 a large amount of cholera blood. In preparing the serum some 

 of the clot is taken out of the blood. In giving the double 

 treatment the serum is used but in addition to this the hogs 

 are at the same time inoculated with a little virulent hog 



