88 Diseases of Poultry 



interpreted includes a number of different diseases distin- 

 guished by the pathologist. The more common are : Con- 

 gestion of the Liver, Inflammation of the Liver, Atrophy of 

 the Liver, Hypertrophy or Enlargement of the Liver, Fatty 

 Degeneration of the Liver, and Jaundice. 



The diagnosis of these different diseases is based entirely 

 on the post-mortem appearances. In no one of them are 

 there any outward symptoms which distinguish it from the 

 others. Vale says it is impossible for the most scientific 

 observer to diagnose either inflammation or congestion of 

 the liver with positive certainty. 



Further not only the symptoms, but also the causes and 

 the treatments of these several diseases are essentially the 

 same. The names of the diseases themselves indicate in a 

 general way the post-mortem appearances. 



For these reasons it seems best to give a brief discussion 

 of the general causes of "liver disease" and the usual treat- 

 ment. This will be followed by a brief account of each 

 disease and its special symptoms and treatment, if any. 



Cause of Liver Disease. — Lack of exercise and over-feed- 

 ing, especially with rich albuminous foods, are the most 

 common causes of diseases of the liver. In addition to 

 these may be mentioned the obstruction of the circulation 

 of the blood by disease of the heart and lungs. Congestion 

 of the liver may be caused by any disease of the crop, giz- 

 zard or bowels that obstructs the circulation of the blood. 



Undoubtedly the larger proportion of liver troubles 

 results from improper feeding and housing. It is a common 

 experience that complaints are more frequent in the latter 

 part of the winter. The birds have been housed for some 

 time without sufficient exercise and fed rich nitrogenous 

 food. These causes operate slowly and since there are no 

 •outward symptoms of liver disease the poultryman is usually 

 unaware of any trouble until his birds begin dying in the 



