174 Diseases of Poultry 



Diagnosis. — ^In early stages of the disease the bird appears 

 normal. Later there is a loss of appetite and an abnormal 

 thirst. The bird becomes inactive, standing with head 

 down, eyes closed, wings dropped and plumage roughened. 

 There is an increase in the rate of respiration and a rise in 

 body temperature. The breathing becomes labored and is 

 accompanied by a rattling sound caused by the vibration of 

 the mucus which collects in the trachea and bronchi. Diar- 

 rhea sets in. The bird becomes emaciated. Death from 

 toxaemia, exhaustion or sometimes from asphyxiation may 

 occur in from 1 to 8 weeks. 



Two types of lesions are found at autopsy. The first type 

 is whitish or greenish yellow membranous patches on the 

 mucous lining of the air passages. They are most often found 

 in the trachea, bronchi, small passages of the Imigs and large 

 air sacs. Occasionally they also occur on the walls of the 

 air sacs in the interior of the bones. Lameness with swollen 

 and inflamed joints results from this condition. They are 

 also sometimes found upon the mucous membranes of the 

 alimentary canal. The mucous membrane underneath these 

 patches is thickened and inflamed. The patch itself is a 

 thick, fibrous, membrane-like mass which contains fungal 

 filaments. These filaments bear spores at the surface of the 

 false membranes. Li fact these patches represent the free 

 grow^th of the mold on the surface of the mucous membrane, 

 having very much the appearance which it presents when 

 growing outside of the body on dead organic matter. The 

 greenish color of the diseased area is due to the greenish fila- 

 ments of the mold or fungus growing upon its surface. The 

 filaments are not all on the surface, however, but they pene- 

 trate deeply into the tissues, causing inflammation and swell- 

 ing, which obstructs the respiration, and at the same time 

 they apparently produce a poison, which causes the general 

 depression and fever. 



