90 DISEASES OF THE DIGESTIVE APPARATUS 



When animals live on the sea-shore we frequently find them affected 

 with bothriocephalus latus. This parasite is found in its immature 

 state in certain fish. 



Tape-worms are very common in dogs; some observers claim as high 

 as 54 per cent, of all animals. In Europe all varieties of the parasites 

 seem to occur according to different speaking countries. The record 

 given by Schones is as follows: Hunting dogs 52.94 per cent, were affected 

 mostly with Taenia serrata; butchers' dogs GG.6G per cent., mostly Taenia 

 marginata; watch dogs confined to the yards and grounds around build- 

 ings 40.44, mostly Taenia cucumerina; work dogs used to pull, 72.22, 

 mostly Taenia marginata; sheep dogs, 57.14 were affected not only with 

 Taenia coenurus to the extent of 7.14, but were also infected with Taenia 

 marginata. Taenia serrata. Taenia cucumerina; pet dogs 70.37, of which 

 36 had Taenia marginata. Taenia cucumerina and 15.74 Taenia serrata. 



Fig. 47. — Taenia echinococcus ; mucous membrane of a portion of the intestine covered with the 



parasites. 



The writer finds in the United States by far the most prevalent is the 

 Taenia cucumerina, occurring in eighty-two of these cases. Taenia serrata 

 ten, and marginata only in two instances, and Taenia echinococcus never 

 observed. 



There is no question that one individual is attacked to a greater 

 extent than others, and the parasite finds more favorable conditions in 

 the mucous membrane of the intestine of certain animals. The parasites 

 may be found in enormous numbers, particularly the Echinococcus 

 when they cover the mucous membrane and give it a velvety appearance 

 (Fig. 47). 



Clinical Symptoms. — "When tape-worms are present they generally 

 cause more or less disturbance in the host, ^^cry decided symptoms, 

 such as chronic intestinal catarrh, can sometimes be attributed di- 

 rectly to the presence of the parasites. Infected animals, as a rule, are 

 restless, great eaters, and in spite of the amount of food they cat -they 

 remain thin. Often they produce the same symptoms as ascarides, 



