CESTODE INFECTION IN CHICKENS 



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of health. Through these means the tapeworms are most harmful, 

 as their effect works more or less indirectly with other diseases. 



I have found instances where the worms were so numerous 

 that they would form such a large compact mass in the intestine 

 as to interfere with passage. These masses imbedded in a great 

 quantity of mucus become lodged at the junction of the small and 

 large intestines with the caeca. 



One species, Davainea echinohothrida, produces nodules or 

 ulcers in the intestinal wall which are often mistaken for other 

 diseases. This has a more serious effect upon the chickens than 

 some of the other species as it has more of a direct pathological 



effect. 



Chickens infested with any of the species of common tape- 

 worms devoured great quantities of food, but upon examination the 

 intestines were usually found empty. It seems as if the food 

 material after reaching the intestine rushes through rapidly on 

 account of the large amount of mucus and the marked diarrhea. 

 This does not allow the bird to obtain as much nourishment as it 

 would otherwise. The cestodes of course absorb their nourishment 

 from the chyme in the intestine. Furthermore, the excretions from 

 the worms may also have some effect upon the general health of 

 the bird, as some are without doubt resorbed into the system from 

 the intestine. 



More practical proof must be obtained by experimental study 

 on the various effects and symptoms of infection in chickens before 

 much can be definitely said on the subject. As yet there is but 

 little known in regard to definite symptoms and effects except in a 

 general way. 



Methods of Control. The subject of the control and treat- 

 ment of tapeworm disease in chickens has not been studied exten- 

 sively. There is need of more experimental data before much can 

 be said concerning it. Several remedies, however, have been tried 

 with some degree of success, although they do not seem practical 

 when large numbers of birds are to be treated. 



A practice general among poultry raisers is to isolate a sick 

 bird and leave it to cure itself, or to kill it. Most poultry men do 

 not take the trouble to treat a sick bird nor do they even try to 

 find out the cause of its ailment, but simply say that it has "gone 

 light." Such an expression covers a multitude of diseases pre- 

 valent among poultry. Birds that are heavily infested with worms 



