72 POULTRY DISEASES 



The infested henhouse should be thoroughly and frequently 

 cleaned and the walls sprayed. The spray should contain 

 some parasiticide as carbolic acid five per cent, creolin five 

 per cent or corrosive sublimate one part in one thousand. 

 The roosts should be scru])bed with ])oiling water and after 

 drying in the sun sliould be saturated Avith kerosene. The 

 litter and straw should be removed from the nests and burned 

 and the nest boxes disinfected before refilling them with 

 straw. If the henhouse be tightly closed, doors, windows, 

 cracks and all openings, and thoroughly fumigated with sul- 

 phur fumes and w^ater vapor, it will aid in destroying lice 

 or other parasites that may be in the cracks and crevices, and 

 difficult to reach with the spray. Fig. 26 illustrates a cheap 

 and convenient spray pump for applying the spray. AA^ith 

 this some force is used which drives the parasite-destroying 

 fluid into the cracks and crevices not possible to reach where 

 it is applied with a brush. 



SCABIES 



The acarids, or mites, as they are commonly called, are 

 exceedingly cojnmon, widely distributed and of great eco- 

 nomic importance. They are eight-legged parasites, belong to 

 the spider family and are so small as to be nearly or quite 

 invisible to the unaided eye, though readily discernible with 

 the aid of a hand lens of low magnifying power. 



There are numerous species of mites that infest birds. Some 

 live on the feathers and scales of the skin, others bore into 

 the skin and still others inhabit deeper portions of the body. 



There is one form of scabies called depluming scabies that 

 is very rare, and so far as the author knows has not been 

 reported in this country. It affects the body of both chickens 

 and pigeons. The one on chickens is the Sarcoptes laevei va- 

 riety gallinae and the one on pigeons is the Sarcoptes laevei 

 variety columhae. 



The acarids parasitic for birds are placed under the fol- 

 lowing genera : sarcoptes, cytodites, trombidium and dermanys- 

 sus. Unlike the various genera of lice, the scab parasites 

 differ greatly in the effects which they produce, and therefore 

 a separate discussion of each one will be given. 



SCALY LEGS— SCABIES OF THE LEGS— FOOT MANGE 



This condition is very common ; it constitutes leg scabies, 

 and is caused by a parasite called the Sarcoptes mutans va- 

 riety gallinae. 



