460 DISEASES OF CATTLE. 



the heart and hings. The liver is congested, but the spleen is always 

 normal. 



Differential diagnosis. — Among the features of this disease which 

 distinguish it from anthrax may be mentioned the unchanged spleen 

 and the ready clotting of the blood. It will be remembered that in 

 anthrax the spleen (milt) is very much enlarged, the blood tarry, 

 coagulating feebly. The anthrax carbuncles and swellings differ 

 from the blackleg swellings in not containing gas, in being hard and 

 solid, and in causing death less rapidly. 



It is difficult to distinguish between the swellings of blackleg and 

 maligant edema, as the}'^ resemble each other very closely and both 

 are distended with gas. Malignant edema, however, generally starts 

 from a wound of considerable size ; it usually follows surgical opera- 

 tions, and does not result from the small abrasions and pricks to 

 which animals are subjected in pastures. Inoculation experiments 

 on guinea pigs, rabbits, and chickens will also disclose the differences 

 between the three diseases above, as all these species are killed by 

 the germ of malignant edema, only the first two species by the 

 anthrax bacillus, while the guniea pigs alone will succumb to the 

 Ijlackleg infection. Hemorrhagic septicemia may be differentiated 

 from blackleg by its affecting cattle of all ages, bj^ the location of the 

 swelling usually about the region of the throat, neck, and dewlap, 

 by the soft, doughy character of the swellings without the presence 

 of gas bubbles, and finally by the characteristic hemorrhages widely 

 distributed throughout the body. Other means of diagnosis, which 

 have reference to the specific bacilli, to the inoculable character of 

 the virus upon small animals, and which are of decisive and final 

 importance, can be utilized only by the trained bacteriologist and 

 veterinarian. 



Treatment. — In this disease remedies have thus far proved unavail- 

 ing. Some writers recommend the use of certain drugs, which seem 

 to have been beneficial in a few cases, but a thorough trial has 

 shown them to be valueless. Others advise that the swelling be 

 opened by deep and long incisions and a strong disinfectant, such 

 as a 5 per cent solution of carbolic acid, applied to the exposed parts, 

 but this procedure can not be too strongly condenmed. As nearly 

 all those attacked die, in spite of every kind of treatment, and in 

 view of the fact that when these tumors are opened the germs of the 

 disease are scattered over the stables or pastures, thus becoming a 

 source of danger to other cattle, it is obvious that such measures do 

 more harm than good and should be put aside as dangerous. Bleed- 

 ing, nerving, roweling, or setoning have likewise some adherents, 

 but the evidence indicates that they have neither curative nor pre- 

 ventive value and therefore should be discarded for the method of 



