CHAPTER XXXII 



PARASITES AND ENEMIES OF POULTRY 



Animals which live on other animals and obtain their nour- 

 ishment from them are called parasites. Many small animals 

 live on birds. These poultry parasites may be grouped 

 in two different classes, internal and external. Internal 

 parasites are those which infest the intestinal tract. External 

 parasites consist of lice and many other minute animals 

 which inhabit the skin and feathers of the bird. Their 

 effect is very detrimental; if present in large numbers, the 

 vitality of the birds is lowered, and they generally become 

 unproductive. Therefore, if the poultry flock is to yield a 

 profit, the birds must be protected from the ravages of these 

 little parasites. 



INTERNAL PARASITES 



Internal parasites are more rarely found in the average 

 flock than external, and are less dangerous. Internal para- 

 sites are commonly called intestinal worms; they are of two 



Fig. 173. — The round worm; an internal parasite of fowls. 



kinds, round and tape worms. The round worm is white, 

 about one and one-half inches in length, and of quite small 

 diameter (Fig. 173) . The tape worm is often two or three feet 

 in length. The presence of either of these parasites will 

 usually retard both growth and egg production, as the para- 



317 



