302 Animal Husbandry 
Throughout the corn-belt of the United States, the loss caused 
by these diseases among swine is not equaled by any other class of 
diseases to which farm animals are subject. They are all con- 
tagious or infectious, and therefore with proper sanitary methods 
they can be prevented, although when the animal once becomes 
afflicted, there isno cure. It is the ravage caused by these diseases 
that makes pork production such a hazardous business. Some- 
times the swine breeder or feeder will have a drove of swine ready 
for the market, when they will contract one of these diseases and 
the entire herd be taken in a few weeks. 
489. Hog cholera. — Hog cholera is an infectious disease of 
swine. It exists in all sections of the United States, but is par- 
ticularly prevalent in the corn-belt. In that section, it is the most 
dreaded disease to which swine are subject. ‘Not so many animals 
are condemned at the large packing houses because of this disease 
as are condemned because of tuberculosis, but this is due to the 
nature of the disease. With cholera, the hogs die or recover 
quickly, while with tuberculosis they may linger for months. 
Cholera varies in its virulence ; sometimes comparatively few hogs 
that have it will die, while at other times nearly every animal in 
the entire herd will succumb to the disease. When the disease 
once appears, it spreads very rapidly, not only among the animals 
of a herd, but across the country from one farm to another. 
490. Prevention of cholera.— Up to the present time, there 
has not been discovered any means by which hog cholera can be 
cured, the only safeguard being prevention. All that is necessary 
to prevent the disease is to keep the germs of the disease away 
from the herd. In the vast majority of cases the germ is trans- 
ported mechanically, in the bodies of sick hogs and on the feet of 
men or animals, including birds. It follows, therefore, that the 
chances of an outbreak of hog cholera will be greatly lessened, if 
not completely avoided, if the herd is protected from these sources 
of infection. To do this the herd should be placed on a part of the 
farm that will be least accessible to men or animals from other farms. 
