DISEASES AFFECTING VARIOUS ORGANS. 67 



Cause: Tuberculosis is due to germs (the tubercu- 

 lar bacilli). 



Symptoms: The symptoms of tuberculosis in fowls 

 are, for the most part, common to other diseases, and 

 the only method of making a positive diagnosis is by 

 microscopical examination of suspected growths or 

 nodules; if the bacillus tuberculosis is found, the 

 nature of the disease can no longer be doubted. 



Fowls afflicted with tuberculosis show unthriftiness, 

 emaciation and rough plumage. Nodules often appear 

 on the face, about the eyes, or the joints of the legs or 

 wings show swellings or small tumors which break 

 down and ulcerate. Post-mortem examination shows 

 white or grey tubercular deposits in the walls of the 

 intestines, lungs and liver. These deposits vary from 

 the size of a millet seed to that of a pea, and may be 

 hard and lime-like, or soft and cheesy, or may even 

 contain small quantities of pus. 



In house parrots the external manifestations of dis- 

 ease is quite common; horny growths appear on the 

 face, about the eyes, or on the bill; the wings and toes 

 often present nodules that are characteristic. The 

 tuberculosis of fowls is not easily communicated to 

 mammals, but that of parrots seems to be identical 

 with tuberculosis affecting man, and is believed to be 

 capable of being transmitted to the latter. 



Treatment: Since the disease can be transmitted 

 from one fowl to another, by close association, and 

 since no cure is possible, all affected birds should be 



