[26 



POULTRY DISEASES AND THEIR TKICATMENT. 



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 (Parasitic Dis- 

 eases of Poultry) 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 attack the duck nor duck-lice 

 the fowl. Nearly every bird has its own particular Mallopha- 

 gan parasite or parasites. They may possibly pass to some 

 strange host for a short time, but they will not live and breed. 



Moreover particular species attack 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 entire body. The 8 known species are described in 

 Theobald's "Parasitic Diseases of Poultry," pp. 23-29. 



The most common and widely dis- 

 tributed hen louse found in this country 

 is Mcnopoii pallidum. This louse is 

 shown in fig. 24. 



Another species of this genus (Adeno- 

 ('011 bjseriatiim) , which closely resembles 

 m. pallidum, is also sometimes found. 

 These are active lice living on all parts 

 of the body. They often crawl on to the 

 hands when handling or plucking birds, 

 and may sometimes be found in the nests. 

 There are several other lice which 

 sometimes infest poultry. Each of these 

 species is confined to a special region of 

 the host. Although capable of crawling 

 about, the lice of these species for the 

 most part remain nearly stationary, often 

 with their heads buried in the skin and 

 s erect. Two species, Lipeurus variabilis and Lipeu- 

 riis hctcrographus, live among the barbs of the wing and tail 

 feathers. Goniodcs dissiinilis is found under the wings and on 

 the rump. The appearance of two of the species mentioned, viz., 



Fig. 24. The common 

 hen louse {Mcnopon 

 paUiduin) Greatly en- 

 larged. (From 

 Banks). 



their bodies 



