PARASITES AND PARASITIC DISEASES OF DOGS 



21 



and the worm attaches with this armed mouth to the lining of the 

 small intestine and sucks blood. Another dog hookworm, the narrow- 

 headed hookworm, Uncinaria stenocephala, is not uncommon in dogs 



Figure 17.— A portion of the 

 small intestine of a dog; slit 

 open to show 6 attached 

 hookworms. Natural size. 

 Adapted from Fiebiger, 1923. 



Figure 18. — The common dog hookworm, 

 Ancylostoma caninum. Head. Dorsal 

 view. Enlarged. From Riley and Fitch, 

 1912, after Looss. 



in Europe and in foxes in the United States and Canada, but appears 

 to be very rare in the dog in this country. This is a smaller worm, 

 the male being one-fifth to one- third inch (5 to 8 millimeters) long, 



Figure 19.— The narrow-headed dog hookworm, Uncinaria stenocephala. Head. Left, dorsal view; 

 right, lateral view. Enlarged. From Riley and Fitch, after Looss. 



and the female one- thud to almost one-half inch (8 to 11 millimeters) 

 long. The mouth is armed with cutting plates (fig. 19), but is 

 without the six teeth which are present in the common dog hook- 

 worm. It is, however, a blood sucker like the other. 



