77i? ii<iAi!i» oi .\(.i;irrr/riii{K. 



Wlien hoiis mit Ictl iipoii swine itliifiiic geruis tlii'.v <lii imi ((iiitrtK-t 

 disease. 



^^'l)on hops aro inofulnfid with cliolora jrorms the tliscaso alVccfs tlio 

 intcstinos. 



When hogs are inocuhited with swiiif playue j^orms the lungs are 

 affected. 



There are other differences between these germs, but those einnuer- 

 iiled should bo sullicient to satisfy tlie general reader. The cause of hog 

 cholera is always the bacillus of hog cholera and of swine plague the 

 bacillus of swine plague, and no case of either of these diseases occurs 

 without the germ being present. Other causes may produce diseases 

 Avitli similar symptoms and may thus be mistaken for these diseases, 

 otlicr causes may so weaken the system as to make the animal easily 

 susceptible to these diseases, or external conditions may be favorable for 

 the distril)ution of the germs. These are secondary causes, but are of 

 great importance. 



The Effect of the Germs Upon the Body.— In hog cholera the germs of 

 hog cholera are found in the blood and in the internal organs. They grow 

 in bunches and as they are carried along in the blood stream to the small 

 arteries and capillaries they act as small plugs to shut off the circulation 

 in the part supplied by the little vessel. At each place the circulation is 

 thus arrested we have a gmall red blotch, so frequently seen in the skin, 

 meat, fat and viscera of hogs that die of cholera. These blotches are so 

 characteris'tic that meat inspectors have no dilhculty in detecting cholera 

 carcasses while hanging upon the gambrel. Another characteristic is 

 that these blotches become redder the longer the time after death, while 

 l>lotches from other causes become paler. 



The spleen, or milt, as it is commonly called, becomes enlarged, soft- 

 ened and tilled with dark blood. 



The intestine is the seat of more or less inflammatory change, partic- 

 ularly in the Pyerian patches and along the lymph tracts. The caecum is 

 especially liable to those changes. In all cases in which the disease con- 

 tinues for some days there is ulceration. The ulcers may be small like a 

 millet seed or as large as a dime. They may be irregular, as in cases 

 which they follow the lymph spaces. The edge of the ulcer projects above 

 the surrounding mucous membrane. The appearance of the surface may 

 be reddish, yellowish or brownish. The edges are not clean cut. but 

 are granular. The ulcer may be only in the mucous coat or in the mucous 

 and muscular, but it is rarely perforating. Hemorrhages sometimes occur 

 as a result of invading an artery or vein. The lymphatic glands along the 

 intestines are always red and swollen and those in other parts enlarged. 

 The contents of the intestine are nearly always black and tarry, and have 

 a very foul odor. In some cases the hog will have eaten clay or other 

 earth, causing very hard, dry faeces. The .stomach is not often seriously 



