58 CLINICAL DIAGNOSTICS. 



resemble that of a hippopotamus. The extremities also swell, the 

 swellings terminating abruptly at the stifle and the elbow. There 

 is a diffuse edema of the lower abdomen; hemorrhage in the 

 internal organs. Breathing is labored and stentorious from the 

 mechanical obstruction (swelling) to the entrance of air into the 

 upper respiratory passages. There is difficulty in deglutition, colic 

 symptoms; and impaired locomotion. When the disease has existed 

 for several days, the temperature increases. [Course atypical, 6 to 

 21 days. Mortality about 50%]. 



VI. Acute Infectious Diseases which Affect 

 the Skin. 



1. Black leg is an acute infectious disease caused by the 

 entrance of a germ through [the digestive tract or] a lesion in 

 the skin, a peculiar emphysema resulting. On the body, shoulder, 

 neck, upper portions of the extremities (never below the knee 

 or hock) appear swellings which are at first hot and painful, 

 but later cold, painless, emphysematous. Incision causes a foamy, 

 fetid fluid to flow out of them. Attending symptoms are high 

 fever, great depression, lameness, dyspnea. Mortality is high. 

 [Prophylaxis, protective inoculation.] 



The bacilli of black leg are contained in the discharges from 

 the swellings. They measure 3 — 5u long, 0.5 — 0.6u broad. One end 

 or the middle is enlarged to receive an ovoid spore which it bears. 

 May be stained by Gram's method. 



2. Malignant edema appears under the same symptoms as 

 black leg; the swellings are more edematous than emphysematous. 



The bacillus of malignant edema is somewhat like the bacillus 

 of anthrax, 3. — 3.5u long and l.lu broad. They are mostly 

 united at their ends to form long threads. In the middle of some 

 of the bacilli or at the ends occur spindle or drumstick-like en- 

 largements to receive the ovoid spore. The spore does not accept 

 ordinary stains. ] 



3. Bovine pest (Wild- und Rinderseuche) is produced by the 

 bacterium of hemorrhagic septicemia and appears in the exan- 

 thematous, pectoral, or intestinal forms. On the head and neck 

 appear large inflammatory edematous swellings, which spread to 

 the mucous membranes of the mouth and throat. The pectoral 

 form is attended by a croupous-hemorrhagic pneumonia with pleu- 

 ritis, and the intestinal form with hemorrhagic enteritis and swell- 

 ing of the intestinal viscera. The Bacterium scpticemiae haemor- 

 rhagicae, like that of contagious pneumonia of swine and of 

 chicken cholera, is 0.6u long, 0.3u broad, oval, stains only at the 

 ends, an unstained belt remaining. 



