SECTION VII 



Constitutional Diseases 



Under this head we class 'Agoing light" and 

 tuberculosis. 



Both cause considerable loss to the poultry- 

 man. There is much doubt as to whether the for- 

 mer should be classed as a disease ; certainly this 

 term as usually applied refers merely to a symp- 

 tom of a disease (often tuberculosis or enteritis) 

 or condition in which there is a progressive loss 

 in the weight of the bird. 



Going Light (Asthen) 



Those who look upon going light as a specific 

 disease consider it as one that affects chickens and 

 pigeons. It may affect old or young birds. It is 

 called going light because the bird becomes grad- 

 ually lighter until emaciated. It is a disease that 

 is found in all parts of the United States. A germ 

 called the Bacterium asthene has been isolated 

 by one investigator from the intestines of sick 

 birds. It corresponds with the Bacillus coli com- 

 munis always present in the intestinal tract of 

 chickens. 



The affected birds have a good appetite; in fact, 

 at times a ravenous one. The loss of flesh is con- 

 tinuous for a few weeks, when the bird dies. 



In eleven cases of going light examined by the 

 pathological laboratory of the United States 

 Bureau of Animal Industry three were found to be 

 infected by the Bacillus enteritiditis. This germ 

 is dangerous to man. It affects cattle and has re- 



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