100 MANUAL OF EQUINE MEDICINE. 



the disease progresses the intervals become still less, until 

 at [length the state of fury becomes permanent, and the 

 horse, prostrated, dies in convulsions on the second, third, 

 or fourth day. 



Morbid Anatomy. — In most cases there are general con- 

 gestions and inflammations in connection with nearly every 

 organ and structure of the body. In the abdomen, ecchy- 

 moses are found on the serous membranes, the liver and 

 spleen are engorged and abnormally friable, and there are 

 extravasations throughout the alimentary canal ; the lungs 

 are congested ; the small air-tubes are filled with mucus ; 

 the heart shows ecchymoses under the endocardium, and 

 may contain fibrinous clots. There is hypersemia of the 

 nerve-centres and nerve-trunks, and patchy congestion of the 

 spinal cord and brain, especially at the base and choroid 

 plexus j and there may be eff'usion into the sub-arachnoid 

 space and ventricles of the cerebrum. 



Microscopical examination of the nerve-centres in dogs 

 shows capillary thrombosis and other changes, especially 

 around that portion of the floor of the fourth ventricle 

 occupied by the respiratory centre. 



The action of the virus appears at first to involve espe- 

 cially the medulla oblongata and the pneumogastric ner^^es; 

 thus the difficulty in swallowing and the convulsions of the 

 respiratory muscles are accounted for. 



Treatment. ^ — When the disease has set in, treatment is of 

 no avail, and it is advisable to shoot the animal. 



Bites by rabid animals should be treated at once. If 

 possible, the tissue around the injury should be excised ; 

 if the wound be superficial, the application of caustics will 

 be sufficient ; if it be deep, the parts must be first excised, 

 and then cauterized or treated by caustics, such as nitrate 

 of silver, caustic potash, or carbolic acid. 



