CHAPTER X 



Internal Parasites 



Fowls are often seriously infested with internal parasites. 

 The most important of these are various worms living in the 

 alimentary canal. In popular usage these are spoken of 

 simply as "worms." Various other internal parasites, as 

 the gape worm, the air-sac mite, etc., are described in other 

 sections of this book. In the main the present discussion 

 will be confined to intestinal worms. 



Few flocks of poultry or indeed few birds could be found 

 which are free from intestinal worms. Worms of one kind 

 or another are found in the intestinal tracts of practically 

 all fowls. Under ordinary conditions these parasites do no 

 very serious harm. Undoubtedly the bird would be better 

 off without them but they are not serious enough to be worth 

 troubling about. Under certain conditions, however, these 

 parasites may multiply to such an extent that they become 

 a serious menace to the flock. There are several cases on 

 record in recent years where epidemics of worms have put 

 whole poultry plants out of business. 



Worms are spread from bird to bird usually through the 

 excrement. The worms or their eggs are expelled by one 

 bird and are picked up along with food and grit by another. 

 Some forms are taken in with the drinking water, especially 

 where fowls are allowed to drink from stagnant pools. 

 Still other forms, like the tape worms, require an intermediate 

 host such as an angleworm, snail, or insect. 



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