At the autopsy of an ordinary case of cholera the first and perhaps the most striking thing seen is the purpling of the skin. On opening the carcass small blood spots may be found under the skin and in the fat cut through. The glands along the intestines are intensely inflamed. The mucous membrane of the stomach is frequently thickened and roughened and in chronic cases there may be ulcers. On opening the intestines we see areas here and there of intense inflammation in the acute cases or numerous ulcers in cases of more chronic type. In very acute cases we find areas intensely inflamed, even bloody in places. The slow chronic cases develop characteristic hog cholera ulcers. These may appear at almost any point on the lining membrane, but more particularly in the blind pouch and around the point where the small intestine connects with the large intestine. On stripping off a very thin transparent membrane covering the kidneys, a typical case of hog cholera will usually show minute red spots on the surface somewhat resembling the covering of a turkey egg, which gives the common name of turkey egg kidney of hog cholera.
=Preventing the Disease.=--Clearly there are certain things which the owner of healthy hogs in a hog cholera district should do and a good many things which he should not do. The same is equally true for the man who has sick hogs in a neighborhood where there are uninfected herds. The owner of healthy hogs and his family should keep away from public stock yards, from all pens and yards on other farms whether sickness among hogs prevails or not. It may easily occur that a neighbor’s hogs may appear well but have recently received the infection and be already capable of scattering the disease. We do not know at what period in the development of this disease infected hogs become capable of disseminating hog cholera.
During a hog cholera season the owner of healthy hogs should institute something in the way of private quarantine and pleasantly, perhaps, but firmly, ask visitors, especially stock buyers and threshing machine crews, to keep at a reasonable distance from the pens and yards. It is safer for one man to have exclusive care of healthy hogs during the hog cholera season, and this man should be very careful where he goes with reference to possible infection. Special fencing or other provisions should be made wherever practical to keep dogs out of the pens and yards, for, under certain conditions, dogs become very active agents in spreading the disease.