Other Diseases of Chickens 303 



gillosis, yellowish tubercles which closely resemble those of 

 tuberculosis occur in the lungs and in the walls of the air 

 sacs and often also in the intestines, mesentery, liver and 

 other organs. In very acute cases the lungs are simply 

 inflamed, death occurring before the formation of the 

 tubercles. The mycelium and spores of the fungus may be 

 found by microscopic examination of the tubercles and this 

 fungus may be obtained by inoculating cultures from these 

 tubercles. 



Etiulogy. — The disease is caused by the spores of an 

 Aspergillus, usually A. fumigatus, Fig. 32. This is a very 

 common fungus and the spores are widely distributed in 

 nature. The spores are often found on the food or on the 

 litter and are inhaled or taken in with the food. Incubator 

 chickens are often infected from the incubators and brooders 

 and hen hatched chickens from the straw or chaff in the nests. 

 Sometimes the chicks get the disease from chick food not 

 properly cared for. It is possible that this disease as well as 

 the coccidial and bacillary white diarrhea is sometimes 

 carried in the egg. The spores and mycelium are often found 

 in the digestive tract of hens and it is not unlikely that they 

 may work up the oviduct from the cloaca and infect an egg 

 before it gets its shell. 



Treatment. — The treatment of diseased chicks is useless. 

 When they are infected the spores develop on the mem- 

 branes and new spores are formed which spread the infection 

 throughout the respiratory system and also to the other 

 organs. The only effective treatment is prevention. Keep- 

 ing the flock under good hygienic conditions with clean food, 

 litter and nesting material reduces the chance of infection 

 and keeps the chicks in a vigorous condition in which they 

 are able to resist the disease. The dead chicks should be 

 burned or buried. 



Prognosis. — The disease is fatal so far as known. 



