110 Hemorrhagic Septicemia of Cattle. 



which occurs very frequently in some enzootics, rarely ter- 

 minates in less than 3 days. 



The prognosis is very unfavorable. According to past 

 observations 85 to 95% of the affected animals die. Recovery 

 may exceptionally be observed in the pectoral form, but even 

 in these cases it is not complete, as in the patients a chronic 

 lung affection usually follows. 



Diagnosis. The disease resembles first of all those cases 

 of anthrax in which edematous swelling and signs of enteritis 

 are present. Hemorrhagic septicemia is indicated by the de- 

 velopment of edematous swelling of the throat, marked swelling 

 of the tongue and the fact that hogs may be simultaneously 

 affected. On the other hand, in anthrax the edema which is 

 less frequent is more apt to develop on the neck, dewlap and in 

 front of the chest ; hogs are only exceptionally, while sheep are 

 frequently affected. On autopsy the absence of acute swelling 

 of the spleen excludes anthrax with a high degree of certainty, 

 while bacteriological examination of the blood from carcasses 

 recently dead of the disease makes differentiation easy on ac- 

 count of the great difference in the appearance of the causative 

 agents. If the carcass is no longer fresh cutaneous or sub- 

 cutaneous inoculations of the blood or inflammatory products 

 are advisable, as the blood of such test animals (mice, rabbits 

 and pigeons) contains the respective bacteria in great numbers. 



From rinderpest hemorrhagic septicemia may be differ- 

 entiated by the fact that the latter may occur without being intro- 

 duced from outside into a locality, and that in its course the 

 mucous membranes, especially those of the air passages, do not 

 show an intense croupous inflammation and ulceration. Blackleg 

 and malignant edema are characterized by crepitating, edema- 

 tous swellings ; moreover, these diseases cannot be transmitted 

 to test animals by cutaneous or small intravenous injections. 



The pectoral form of hemorrhagic septicemia can easily 

 be mistaken for pleuro-pneumonia. In the majority of cases 

 hemorrhagic septicemia may be recognized by the appearance 

 of inflammatory changes in the lungs, as they occur in this 

 disease in larger extension or in numerous centers of the same 

 stage of development. Occasionally, however, the lesions may 

 simulate acute or subacute pleuro-pneumonia to such an extent 

 as to render diagnosis from the macroscopic findings almost 

 impossible. In such cases a microscopical examination will 

 establish the correct disease, as in hemorrhagic septicemia the 

 serous fluid of the lungs contains bipolar bacilli, while in pleuro- 

 pneumonia the findings are negative. Test inoculations may 

 also be made to differentiate the disease, as the virus of sep- 

 ticemia is pathogenic for practically all test animals, while 

 that of pleuro-pneumonia is harmless (in calves infected sub- 

 cutaneously with the latter an edematous swelling develops at 

 the point of inoculation in 1 to 2 weeks). The presence of 



