2 BULLETIN 260, U. S. DEPARTMENT OP AGRICULTURE. 



As has been said, the dog himself has many delightful and useful 

 qualities. It is our thoughtless tolerance of his present unwar- 

 ranted liberty and license that permits this survivor of the days 

 when the dog was man's faithful and valuable ally against the rest of 

 the animal world to become a pest and a danger. There is a growing 

 conviction that while his innate qualities and the fund of affectionate 

 sentiment which attaches to him warrant the preservation of the dog 

 with a responsible owner who will keep him clean and free from 

 vermin of all sorts, hold him within reasonable bounds and restraint, 

 and assume responsibility for his acts, on the other hand, the owner- 

 less dog, the dog which carries vermin and disease, the dog which 

 kills sheep or destroys property of any sort, the trespasser — these 

 dogs must be eliminated. 



The case against the unrestricted dog is based on two counts — that 

 he is a nuisance and that he is dangerous. 



That most dogs are allowed too many liberties and too much 

 familiarity with people is a matter of common knowledge. Trans- 

 gressions on the part of dogs range from simple trespass to the habit 

 of biting without provocation and to the wanton killing of sheep. 1 



The direct monetary damage done by unrestricted dogs, while great, 

 is even less important than the indirect harm they work as carriers of 

 disease. It is the purpose of this paper to show how improperly- 

 cared-for dogs act as agents in the spread of diseases, particularly 

 parasitic diseases, affecting man and live stock. 



DISEASES AND PARASITES CARRIED BY THE DOG. 



Dogs probably play a part in the spread of diseases due to fungi, 

 such as ringworm and f avus, and are sometimes important carriers of 

 bacterial and filterable-virus infections. In the recent outbreak of 

 foot-and-mouth disease, it was determined beyond any reasonable 

 doubt that dogs were responsible in some instances for the spread 

 of the disease, not only from one farm to another, but from one State 

 to another. The dog is of primary importance and in many instances 

 the sole carrier in the case of many dangerous and even deadly animal 

 parasites of man and the domestic animals, and is especially notorious 

 as the carrier of rabies. Some of these parasites depend so absolutely 

 on dogs as carriers during certain stages of their life history that they 

 would probably or certainly become extinct if dogs were not avail- 

 able as hosts. The long list of important diseases and parasites which 

 are conveyed by the dog to man and the domestic animals and which 

 are present in this country is as follows : Rabies in man and stock ; 

 hydatid in man and stock: gid in stock (and possibly in man also) ; 



1 See Farmers' Bulletin 652, " The Sheep-Killing Dog." 



