316 DISEASES OF CATTLE, SHEEP, GOATS, ETC. 



testinal tract of the herbivora. It may be brought to the surface of 

 the soil by growing plants, rains, winds, or burrowing insects and 

 rodents. In animals that have succumbed to the disease the germ is 

 confined to the seat of infection, but a few hours after death it may 

 migrate to other parts of the body through the blood channels. The 

 bacillus may attack man, horses, asses, goats, sheep, pigs, cats, dogs, 

 and poultry. Adult cattle, although refractory to experimental in- 

 oculation, suffer from natural infection, while calves are susceptible 

 to both of these methods of exposure. (Kitt.) The introduction of 

 the bacillus into abrasions of the skin and superficial sores rarely 

 does any harm, because the germ is quickly destroyed by contact with 

 air. If, however, the organisms are inserted deeply into the sub- 

 cutaneous tissues of susceptible animals, they quickly develop, pro- 

 ducing a soluble poison, which is the fatal agent. 



In lamb-shearing season, or after docking or castration, the mor- 

 tality is higher among these animals because of wounds inflicted at 

 such times. The application of antiseptics to wounds thus made will 

 reduce the percentage of deaths to a minimum. 



Symptoms. Usually the first symptoms are overlooked. In the 

 early stages the animal appears listless, disinclined to move about, 

 and seeks the shady and quiet places to lie down. If forced to move 

 about, the hind legs are drawn forward with a peculiar stiff dragging 

 movement and there may be slight muscular trembling all over the 

 body, which becomes more intense as the disease progresses. When 

 driven, the animal shows signs of fatigue, ultimately dropping to the 

 ground completely exhausted. Breathing becomes fast and painful, 

 with frequent spasmodic jerks. 



The pulse is quick and weak and the temperature is 106 to 107 

 F. An edematous, doughy, and painful swelling appears at the 

 point of infection. This tumefaction spreads more and more and 

 will crackle on pressure. In case of an open wound a fetid, liquid, 

 and frothy discharge is observed. The center of the swelling may 

 appear soft and jelly-like, while the margin is tense, hot, and pain- 

 ful. The symptoms increase rapidly, resulting in coma and death. 



Lesions. After death the fat and subcutaneous tissues surround- 

 ing the infected area are infiltrated with a yellow gelatinous material 

 containing an orange-colored foam, due to the presence of gas bub- 

 bles. The muscles at this point are friable, spongy, and of a uniform 

 brownish tint, disassociated by gas and a blood-tinged exudate. This 

 gangrenous tissue, when present before death, can be removed with- 

 out pain to the animal. The intestines are generally normal, but 

 they, together with the peritoneum, may be inflamed, and the lungs 

 are usually the seat of an edema. The spleen, liver, and kidneys 

 retain their normal appearance, in marked contrast with anthrax. 



Differential Diagnosis. Unlike blackleg this disease never ap- 

 pears as an epizootic but in isolated cases. It may also be differen- 

 tiated from the former by the history of a recent parturition or sur- 

 gical operation, by the presence of an external injury at the site of 

 the swelling accompanied by a fetid liquid discharge, and the gan- 

 grenous appearance of the tumefaction. Man is susceptible to malig- 



