206 



Diseases of Puidtry 



A. LICE (MALLOPHAGA) 



Lice are probably the most widely distributed parasite of 

 poultry. They are so common that flocks of fowls that have 

 not been treated to remove lice for a long time are almost ' 

 sure to have one or more species present. At least 8 species 

 of hen lice have been found and 5 of these are common. 

 Bird lice are quite different from 

 those which affect man and mammals. 

 The popular notion that lice may 

 be transmitted from poultry to other 

 animals is quite erroneous. Theobald 

 says : " So particular are bird-lice 

 that it is quite the exception to find 

 one species upon two distinct kinds 

 of birds. Fowl-lice will not even at- 

 tack the duck nor duck-lice the fowl. 

 Nearly 'every bird has its own partic- 

 ular Mallophagan parasite or para- 

 sites. They may possibly pass to 

 some strange host for a short time, 

 but they will not live and breed. 

 IMoreover, . . . particular species at- 

 tack restricted areas on the same 

 host and are seldom found in other 

 positions." Some of these lice are 

 sluggish, nearly stationary, and confined to a restricted area 

 of the body, while others are active and crawl over the en- 

 tire body. Theobald describes eight species of lice found 

 on poultry. 



The most common and widely distributed hen louse 

 found in this country is Menopon ixiUidum. This louse is 

 shown in Fig. 36. 



Another species of this genus {Menopon hiseriahim), which 



Fig. 3G. — The common 

 hen louse {Menopon pal- 

 lidum). Greatly enlarged. 

 (From Banks.) 



