272 ■ Hog- Cholera. 



may reach the size of a wahiiit, and contain caseous masses. 

 Such are most often found in the liver, the kidneys, kings, spleen, 

 udder, ])one marrow, etc. The lungs may in exceptional cases 

 also contain circumscribed pneumonic areas, with a yellowish- 

 gray cut surface, without necrosis or pleurisy (Preisz). 



In the pharynx, at the base and on the borders of the tongue, 

 sometimes also in other parts of the buccal cavity, and in the 

 larynx hemorrhagic inflammations of the mucous meml)rane, 

 with croupous pseudo-membranes and ulcerations, together with 

 a superficial or deep necrosis may very frequently be found. 



Among other changes which may occur are necrosis of the 

 mucous membrane of the gall bladder, the vagina, and the blad- 

 der, localized or extensive necrosis of the skin, cloudy swelling 

 of the parenchymatous organs, etc. 



Fig. 51. So called button on the mucous memljrane of tlie large intestine in hog cholera. 



The intestines of animals slaughtered during convalescence 

 show at the places of the thrown-off necrotic nodules, ulcera- 

 tions with a granulating base, or small white scars may serve 

 to indicate the pre-existing ulcerations (Gerosat and Bilitz ob- 

 served in exceptional cases cicatrized constrictions of the intes- 

 tines). The lymph glands of other organs may at times also 

 contain caseous foci. 



The bacillus suipestifer may be demonstrated only in acute 

 cases in the blood, and even then only in small numbers, while 

 in the spleen it may be present in greater numbers. The same 

 organism may also be found in the affected lymph glands, in 

 the necrotic nodules of the intestinal mucous membrane and in 

 the caseous metastatic lesions of the internal organs. 



The necrotic and xdeerative processes on the intestinal mucous membranes 

 develop quite slowly. Thus in an animal 12 days after the infection there are, 

 besides the bean-sized mesenteric lymph glands, only hemp-seed size yellow 

 deposits of exudate on the intestinal mucous membrane; after 14 days they attain 

 the size of a lentil, and after 18 days the exudate or ulcerations may be the size 

 of a dime. At this stage the mesenteric lymph glands reach the size of an almond; 



