478 DISEASES OF THE SKIN 



The afflicted animals are often affected with secondary eczema. 

 This, however, is produced by constant scratching, due to the irritation 

 of the disease. 



Therapeutic Treatment. — The treatment' of herpes depends on the 

 removal of the favus. We must, therefore, clean the affected part, lift 

 and remove all scabs and eschars by means of a thin knife, or shampoo 

 with soft soap, following it up by a dressing of some of the agents men- 

 tioned under the head of jNIange. 



Prophylaxis. — The animals must be separated, as the danger of 

 infection to both clog and man is very great. The kennels are to be 

 cleaned, and all straw, etc., l)urned, and the animals kept away from 

 children. 



Trypanosomiasis. 



Under this term we class numerous infectious diseases peculiar to 

 tropical countries. These various conditions are, generally speaking, 

 due to a flagellate protozoon present in the blood (protozoa flagellata). 

 Some of the diseases, such as the nagana of Africa and the surra of 

 India, are easily transmitted to the dog by inoculation. The parasite 

 of the nagana and the surra (trypanosoma brucei) is transmitted by the 

 sting of certain insects (tsetse fly of Africa and the tropical horse fly of 

 India). Under the microscope it is easily recognized by the low power. 

 It is worm-like in form, having a blunt posterior extremity, its length 

 depending on the animal it inhabits. In the dog it is extremely short. 



The symptoms of the disease are elevation of the temperature, 

 which may be intermittent, oedematous swellings, especially of the 

 posterior extremities and of the thigh, scrotum, and face; pustular erup- 

 tions of the skin which may heal up and leave the animal bald; opacity 

 of the cornea, and finally paralysis of the posterior extremities. Death 

 generally occurs in three to four weeks. Blin states that when dogs im- 

 ported into India and China, contract the disease it is almost invariably 

 fatal, but native dogs generally make good recoveries. 



