FOURTEENTH ANNUAL YEAR BOOK— PART X. 737 



bodies of the birds wliich have died or are killed, as well as all the 

 accumulated manure, sweepings and scrapings of the poultry houses, 

 should be completely destroyed by fire. 



So far as known there is no danger of communicating the disease to 

 man by eating the cooked flesh of tuberculous fowls. In most cases, 

 however, the diseased birds are so emaciated and their general health 

 so affected by fever and diarrhoea that their flesh is not fit for human 

 consumption. It is better in all cases to burn the carcasses of the birds 

 in which tubercular nodules are found, and thus avoid all danger of 

 the disease being communicated to either man or animals. 



ASPERGILLOSIS. 



One of the common molds, called Aspergillus fmnigatus, sometimes 

 attacks the respiratory or digestive organs of fowls, producing either 

 whitish or yellowish tubercle-like nodules in the tissues or large, flat 

 elevations of a dirty yellow or greenish coloration on the surface of the 

 mucous membranes. Each of the nodules contains a growth of the mold 

 at its center, which is inclosed and imprisoned by a wall of animal cells. 

 The flat elevations, however, represent the free growth 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 

 filaments of the mold or fungus growing upon its surface. The fila- 

 ments are not all on the surface, however, but they penetrate deeply 

 into the tissues, causing inflammation and swelling, which obstructs 

 the respiration, and at the same time they apparently produce a poison, 

 which causes the general depression and fever. The changes caused by 

 the development of this fungus are most frequently seen in the mouth, 

 the trachea, the bronchial tubes, the lungs, and the air sacs, but they 

 may also occur in the alimentary canal. 



Causation. — The Aspergillus fumigatus is a very common fungus of 

 great vegetative and resisting powers which is found everywhere grow- 

 ing upon dead organic matter of the most varied kinds. Its develop- 

 ment is favored by warmth and moisture, and its spores are often found 

 in enormous numbers in musty or moldy hay, straw, or grain. The 

 mucus on the surface of the membranes, the serum beneath them, and 

 the temperature of the bird's body are all favorable to its growth, while 

 in addition it has the power to resist the efforts of the animal tissues to 

 overcome and dislodge it. Having such characteristics, this fungus is 

 one to be excluded so far as possible from the habitations of poultry, for 

 otherwise it may cause severe and fatal disease. 



The spores of aspergillus are most frequently introduced with moldy 

 hay, straw or chaff that are given to the fowls to scratch in. Often 

 the fungus grows on accumulations of manure, old leather, and similar 

 substances when they are sufficiently moist, and produces spores in 

 enormous numbers. Not all birds are susceptible to its attacks, and it 

 seems to be the delicate breeds and the weak individuals which are most 

 frequently its victims. 



Symptoms. — This disease may be limited to a single bird or it may 

 affect a large number. When the air tubes or lungs are attacked the 

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