210 Manual of Veterinary 31icrohiology. 



abdomen, on the perineum, groins, limbs, and at the 

 root of the ears, these regions then taking a more or 

 less pronounced red or violet color, and thus tending 

 to increase the chances of confounding it with rouget. 

 These cutaneous changes, however, are less constant 

 than in the last disease. 



Pneumo-enteritis is of rather long duration : twenty 

 to twenty-five days on an average, never less than 

 eight to ten days ; it may extend to five or six weeks ; 

 it is very contagious, and few hogs which have been 

 exposed to the contagion escape. 



In very rapid cases the autopsy shows, beside ec- 

 chymoses disseminated through the connective and 

 inter-muscular tissue, peritoneum, pleura, pericardium, 

 and heart, a violent inflammation of the stomach and 

 intestines, with interstitial hemorrhages and erosions 

 or ulcerations at Peyer's patches; the mesenteric 

 glands are voluminous and Infiltrated; the lungs are 

 normal or show lobular foci of hemorrhagic congestion. 

 When the evolution of the disease has been slow the 

 lesions are better defined; those of the intestine, 

 cfficum, and large colon are especially remarkable ; 

 the wall of these organs is considerably thickened and 

 indurated, and has become rigid. The swelling and 

 induration chiefly aflfect the Peyer's patches ; these 

 are the seat of a necrotic process which leads to the 

 formation of grayish colored diphtheritic exudates and 

 ulcerations of greater or less extent, both in area and 

 in depth. The inflammation sometimes extends to 

 the peritoneum. 



The lungs show lesions of broncho-pneumonia at a 

 more or less advanced stage; pleurisy is also occasion- 

 ally present. 



