ACUTE INFECTIOUS DISEASES. 87 



3. Blackleg. 



Black quarter; quarter ill; symptomatic an- 

 thrax; gangrenous emphysema. 



Cause: The Bacterium Chauveaui, a rather 

 thick, straight germ, with rounded ends. It is a 

 very difficult organism to eradicate, as the spores 

 may live for years. 



Symptoms: Only the greatest of care will enable 

 one to differentiate this disease from certain forms 

 of poisoning in sheep. 



On the range the course of the malady is very 

 rapid. When first seen, the animal has difficulty 

 in walking; its abdomen is distended from bloat- 

 ing; a frothy discharge is seen oozing from the 

 mouth, and the temperature is very high. The 

 herder immediately diagnoses the trouble as pois- 

 oning, and many more die before expert assistance 

 is sent for. When local symptoms are pronounced, 

 such as crepitating swellings on the hindquarters, 

 the diagnosis is comparatively easy to make. 



Treatment: Purely preventive. This is done by 

 immunization and removal to another range. 

 Blackleg is rather rare among sheep, but one out- 

 break that came to the author's notice caused the 

 death of over four hundred sheep before expert 

 assistance was even called. Every known anti- 

 dote for poisoning had been used to no avail. 



4. Bradsot. 



Braxy; gastromycosis ovis. 



This is a disease much resembling blackleg. It 

 is very destructive to sheep in Norway, Iceland, 



