180 Disea.scs of Poultry 



To reduce the con<i;ested condition of the lungs a counter 

 irritation may be applied to the skin of the back over the 

 region of the lungs. This may be done by raising up the 

 feathers and painting the skin with tincture of iodine. 



Prognosis. — This disease is more easily prevented than 

 cured. A number of cases recover if placed in a warm dry 

 room. Treatment is of little value. A large percentage of 

 the birds die. 



Tuberculosis 



This disease is discussed in Chapter IX. It is primarily 

 a disease of the abdominal viscera. Lesions occur also in the 

 lungs in about one case in five. The infection of the lungs is 

 usually of secondary origin. 



The Air-Sac Mite 



A species of mite (Cytodites nudus) infects the air-sacs and 

 bronchi of poultry. 



Diagnosis. — When the birds are not badly infested there 

 are no external symptoms. If badly infested the bird may 

 become anaemic and listless and finally die of exhaustion. Or, 

 if the air passages are seriously obstructed by the collection 

 of parasites and mucus, there will be a rattling in the throat 

 and coughing, and death may result from suffocation. The 

 presence of the parasites is often found only on examination 

 of dead birds. They appear as a yellow or white dust, each 

 particle of which is a mite. If closely watched the particles 

 may be seen to move. 



Etiology. — The mite probably enters the air-sacs by 

 crawling in the nostrils and finding its way down the trachea 

 and bronchi to the sacs. The parasites are able to live only 

 a short time outside the bird's body. The mouth parts of 

 these mites are modified into sucking tubes. They attack the 



