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DISEASES OF THE DIGESTIVE APPARATUS. 



absorption of materials necessary for their nutrition does not fail 

 to exert a debilitating influence upon the affected animals. 



The principal symptom observed in animals whose intestines 

 contain many worms are as follows: 



1. Emaciation and disturbances of nutrition (anemia and ca- 

 chexia) ; 



2. More or less intense gastro-intestinal catarrh and intestinal 

 hemorrhages ; 



3. Constipation and its consequences ; colics ; 



4. Nervous phenomena of very numerous forms and degrees. 



But these symptoms have nothing characteristic ; they are some- 

 times observed without auy helminthiasis being noticed, and in 

 many animals they are wanting, even when the intestine contains 

 numerous parasites. However, they acquire a genuine importance 

 when accompanied by the expulsion of worms. In this latter case 

 we must avoid making a diagnosis of helminthiasis before having 

 made a complete examination of the patient, for the phenomena 

 detected may be related to other affections. Facts which are ex- 

 tremely common show that intestinal worms sometimes exist in 

 large numbers, and yet the animals have all the appearances of 

 perfect health. 



The course of helminthiasis depends upon the species and quantity 

 of the parasites. Its termination is sometimes fatal in the case of 

 young animals, in which it readily produces anemia and cachexia. 



The prophylaxis is only possible, in the present state of our 

 knowledge, for a very restricted number of helminths {Tœnia 

 echinocoecus, T. Cœnurus, Trichina spiralis) ; in most cases we 

 cannot even suspect the presence of eggs or larvae in the food or in 

 the water. 



When there is any reason to suspect the existence of helminthiasis 

 we may insure the diagnosis by using anthelmintics. As soon as it 

 is clearly established, we must institute a treatment which will vary 

 according to the species of the parasite, and also that of the animal 

 which constitutes its host. 



I. Plathelminths (Tapeworms). 



The most important species in our domestic animals are : 

 A. In the dog : 1. Tœnia cucumerina, which is the most fre- 

 quent ; according to Melnikow, its larva is found in the Pulex 



