SOME COMMUNICABLE DISEASES 369 



terized by fury. The patient bites objects, other animals and per- 

 sons that may cross its path. He has a tendency to stray from 

 home. The voice is hoarse and the animal does not respond to his 

 master's voice. (3) The paralytic stage follows. By this time 

 the dog is thin, haggard, and loathsome in appearance. He is 

 unable to swallow, the jaws become paralyzed and hang down, 

 and the hind quarters become weak. Finally death occurs at 

 the sixth or eighth day. 



Dumb rabies differs in that the patient does not exhibit mania. 

 In this form paralysis occurs early and death takes place in two or 

 three days. 



The first symptoms in horses and cattle are restlessness and 

 hypersensitiveness. Later the animal becomes furious, and 

 viciously bites and kicks at any object within reach. The course 

 of the disease is five or six days. Paralysis and death are the 

 inevitable end. 



Little difficulty should be had in differentiating rabies from 

 other nervous disorders, as in none of them does the animal ex- 

 hibit the same symptoms of maliciousness. If any doubt exists, 

 small pieces of the brain should be examined by a trained labora- 

 tory diagnostician with the aid of the microscope for the pres- 

 ence of Negri bodies. When found these bodies are considered 

 positive evidence of the disease. In the horse they are very small 

 and usually confined to limited areas. Inoculation of rabbits 

 with material from the brain of an infected animal is a reliable 

 means of recognizing the disease. 



Treatment. — There is no practical treatment for rabies in farm 

 animals. In man the Pasteur treatment gives good results. It 

 consists in injecting daily for fifteen days an attenuated virus, 

 the virulency of which is increased with each successive injection. 

 Rabies may be effectively controlled and prevented by (1) in- 

 forcing a dog tax, (2) by keeping all stray dogs off the streets, 

 and (3) by muzzling all dogs allowed to run at large. 



STRANGLES 



Strangles, commonly called colt distemper, is a communicable 



disease peculiar to young animals of the horse family. It is 



characterized by fever, profuse catarrh of the nasal mucous 



membrane, and marked swelling of the submaxillary lymph- 



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