210 DISEASES OF POULTRY. 



apparent by the loss of weight, wasting of the 

 muscles, and prominence of the bones. The comb 

 becomes pale, the bird loses its .bright, animated ex- 

 pression, and in the later stages becomes quite dull 

 and sleepy. At this time a persistent diarrhea appears 

 which increases in intensity until the subject dies from 

 exhaustion. 



The symptoms just enumerated are those observed 

 when the disease is confined to the internal organs. 

 It often affects the joints and bones, when it is re- 

 vealed by lameness, swellings of the joints and de- 

 formities of the bones. Occasionally ulcers form, in 

 the pus of which many bacilli are found. 



The skin and external mucous membranes are 

 frequently affected with parrots but more rarely with 

 other birds. There are first seen small grayish eleva- 

 tions which unite and form patches. Thick crusts 

 form on these patches, becoming hard externally and 

 soft and cheesy next to tissues. If these crusts are 

 removed a red granular surface is exposed. Some- 

 times the crusts, particularly near the eye or mouth, 

 become horny and develop into excrescences an inch 

 or more in length. 



Appearance of the' Organs. — In poultry and 

 pheasants the abdominal viscera are the most common 

 seat of the disease. The liver is most frequently and 

 most severely affected. The spleen is also very often 

 attacked. 



These organs are enlarged and more or less filled 

 with tubercles which may vary in size from small 

 whitish or grayish points, to nodules the size of a pea, 

 or to tumors the size of a walnut which are fibrous, 

 firm and often softened at the center. The tubercles 

 may also be hard and calcareous. The liver is more 



