CHAPTER IX. 

 DISEASES OF THE LIVER. 



Fkom the phYHiolosieal standpoint the liver is an organ of such im- 

 portance that its pathology should he studied as completely as possible. 

 Furthermore, it is often the seat of a number of varying lesions, either of 

 parasitic, toxic, infectious, or cancerous origin. 



In animals of the bovine species the liver is placed in the right retro- 

 diaphragmatic region, so that it is somewhat difficult to examine by any 

 of the ordinarj' methods, like palpation and percussion. Under normal 

 conditions it is entirely concealed beneath the hypochondrium, except 

 towards the upper margin of the thirteenth rib, where it can be examined 

 by palpation. When, as in various morbid conditions, it is considerably 

 increased in size, it extends as far as the margin of the hypochondriac 

 circle, thus becoming directly accessible to palpation and percussion. 

 Sometimes it even enters the hypochondriac region, passing outside the 

 omasum and abomasum, which it then thrusts towards the middle of the 

 abdominal cavity. 



The margin of the liver exhibits a depression lodging the gall bladder 

 nearly opposite the centre of its vertical depth. 



As the liver is so deeply situated, percussion is found to be the method 

 of examination which gives the best results. Beyond the limits of the 

 zone of auscultation, percussion gives above a semi-dull sound, then, 

 proceeding downwards, a dull sound due to the liver, the omasum, and 

 the collection of liquid in the bowel. AVhen this dulness is well defined, 

 clear, broad from above downwards, and extends to or beyond the hypo- 

 chondrium, it indicates hypertrophy of the liver. By deep palpation of 

 the posterior margin of the hypochondrium the liver can then be sounded, 

 and its excessive size detected. 



The symptomatology of the liver is still very imperfectly understood, 

 for in practice the urine is rarely tested for bile pigments, nor attempts 

 made to ascertain whether the glycogenic function is normal by the test 

 for alimentary glycosuria. 



In this connection nothing has yet been done to assist in diagnosing 

 certain hepatic conditions. Fortunately, those diseases of the liver 

 which we have to study are more often of a parasitic nature than true 

 diseases of the hepatic tissue. 



