DISEASES OF SWINE 453 



tuberculosis and anthrax, which are highly dangerous to man, and 

 for this reason care should be exercised in examining carcasses of 

 sick hogs so as to avoid a cut or scratch on the hands which might 

 serve as a point for the inoculation of disease. 



The post-mortem examination of a hog should begin with the 

 skin, which may show the red or purplish blotches which have been 

 mentioned above as one of the symptoms of hog cholera. When the 

 examination of the skin has been made, the organs of the body are 

 examined in the following manner: The hog is laid on its back, and, 

 beginning at the throat, an incision is made along the middle of the 

 chest and belly, through the skin and underlying fat, and extending 

 the entire length of the body. The next step is to dissect back the 

 skin of the chest so that the ribs are exposed. Now, beginning at 

 the lower border of the ribs, about 1 or 2 inches on either side of the 

 breast bone, and cutting toward the head, the ribs on both sides are 

 severed, the central portion, including the breast bone, being removed 

 entirely. Crosswise incisions, extending from the first long incision 

 toward each leg, are now made in the skin in such a manner that 

 this may be laid back on both sides of the body, thus exposing to 

 view the various organs which lie in the chest and abdominal 

 cavities. While the carcass is being opened, care should be taken to 

 avoid injuring the organs. The important organs are examined as 

 follows : 



Lungs. The healthy lungs are pink in color, soft, and filled 

 with air. Occasionally, in that portion of the lungs nearest the neck, 

 small, solid, dark areas may be seen in healthy hogs. Such areas 

 without other lesions are not to be regarded as indicating hog cholera. 

 In acute cases of hog cholera the surface of the lungs frequently 

 show numbers of small red spots of varying size which are caused by 

 the rupture of minute blood vessels, thus allowing the blood to escape 

 into the tissue. These spots can not be washed off with water and 

 when found are an important indication of hog cholera. It is not 

 unusual to find that large portions of the lungs are consolidated, and 

 instead of being soft, filled with air, and pink in color, as is the case 

 in normal lungs, the organs are heavy, solid, and of a grayish or 

 dark-red color. This consolidation of the lungs is not so characteris- 

 tic of hog cholera as the reddish spots mentioned above. 



Other Organs. The heart is inclosed in a thin membranous 

 sac which can be easily slit open and removed so as to permit a satis- 

 factory examination of the organ. In cases of hog cholera, the sur- 

 face of the heart may show bloody-looking blotches similar to those 

 seen in the lungs and which, like those in the lungs, can not be 

 washed off with water. These bloody spots on the heart are rarely 

 seen except in very acute and virulent forms of hog cholera. In 

 cases of hog cholera the liver generally shows no marked change 

 from the normal condition. It may be at times darker than normal 

 in color, and if cut with a knife blood will exude. This indicates 

 simply that the organ is congested. In some cases the liver may be 

 of a light-grayish color, due to the increase of fibrous substances. 

 Neither of these conditions is especially characteristic of hog cholera. 



