EXTERNAL PARASITES 39 



ditions. During their development they moult frequently, 

 sometimes as often as ten times, becoming slightly darker 

 with each molt. 



Lice breed with great rapidity ; it has been com- 

 puted that the offspring of a single pair would 

 reach the enormous total of 125,000 individuals 

 in the third generation, which may mature in 

 eight weeks ! 



Effects of Louse Infestation 



Chicks hatched in the incubator are free from 

 lice and stay so until placed with lousy hens or 

 chickSj or in quarters infested by lice. Lice pro- 

 duce much irritation. The effect of large num- 

 bers upon birds is quite marked. The lousy birds 

 scratch, pick at the feathers, show signs of being 

 drowsy, may refuse to eat, and, in growing birds, 

 the body develoj)ment or growth is interfered 

 with. 



Young chicks infested with lice often sit 

 around, moping, with wings hanging down, and 

 in a week or two mav die. For this reason 

 brooder chicks should thrive better, grow faster, 

 and are freer from manv ailments than chicks 

 hatched bv the hen. It has been said that a lousv 

 bird will have more of a tendency to wallow in 

 the dust than one not so infested. 



The effect upon older birds is not so severe 

 as upon younger ones, but is noted in conditions 

 of flesh and in the production of eggs. The irri- 

 tation is sometimes so severe that hens desert 

 their nests. Their combs mav become dark or 

 black. Birds unable to rest day or night, become 

 emaciated and die. 



To find the lice, part the feathers and the lice 

 will be found running over the skin or base of 

 the feathers. A favorite location for lice is under 



