80 



P0T7.TRY DISEASES 



conceal nient in the daytime. It is the most common and most 

 injurious of mites and is present in every poultry house un- 

 less it is kept unusually clean. It comes out at night and 

 makes its attack. Few of these parasites are to be found on 

 the birds (chickens and pigeons) in the daytime, but at night 

 they may be numerous. Birds so harassed at night cannot 

 sleep or rest and soon become emaciated. The laying hens 

 will leave their nests and even cease laying. Birds may be 

 found dead under the roosts in the mornings from the attacks 

 of these mites. 



These parasites may also attack horses and other animals 

 kept close to the quarters of infested birds ; they cause irrita- 

 tion, the animal scratches, rubs, and unable to rest at night, 

 becomes thin in flesh, and weak. Some persons are annoyed 

 by them. 



Treatment. — The same as has been outlined for lice and 

 chiggers. (See page 72.) 



FLEAS AFFECTING BIRDS 



One genus and species of Hea parastic upon the chickens 

 is known, technically, as the Pulex avium. It is far more 

 common in the southern half of the Ignited States than it is 

 in states farther north. 



Pulex Avium 



Description. — This is the common chicken flea. It resembles to 

 some extent the flea that infests dogs- and man. however, a micro- 

 scopic study shows it to be a distinct species. Fig. 32 illustrates 



this parasite. It is provided with 

 antennae or jointed feelers. In 

 the larval state its mouth parts 

 are arranged for mastication and 

 in the adult for wounding the 

 skin and sucking blood. It is flat- 

 tened laterally, the thorax being a 

 trifle deeper than the head and 

 is provided with three pairs of 

 legs, of which the posterior pair 

 are longer than the others, giv- 



FiG. 32. Pulex Avium. 



A, antennae; B, stylet; C, booklets 

 on free extremity of leg. 



great power to 

 extremity of the 



with two hook- 

 In color the 



light to dark 



ing the insect 



jump. The free 



legs is provided 



lets or claws. 



chicken flea is 



brown. 

 Life History. — The female lays about twenty brown oval eggs in 

 some dirty, dusty place, such as the floor, cracks, crevices or nests. 

 These eggs hatch in a few days (six to twelve) if the temperature 

 be warm, and from them come wormlike larvae composed of thirteen 

 segments each. The mouth parts are arranged for mastication. 

 The larval stage lasts about eleven days: they then pass through 

 the pupa stage in a tough brown cocoon. The pupa stage lasts about 



