168 THE MODERN HORSE DOCTOR. 



DISEASES OF THE LIVER. 



JAUNDICE. —(Icterus.) 



Definition. — A yellow discoloration of the tissues, caused by 

 an interrupted excretion of bile. 



On making post mortem examination of animals having been 

 the subjects of this disease, we find the yellow tinge pervading 

 every part of the organization. It is diffused through the whole 

 of the muscular, fatty, cartilaginous, cellular, bony structures, 

 and has also been detected in the brain. 



Mr. Percivall considers "jaundice to be an unfrequent disease 

 among horses ; and one reason appears self-evident, as soon as 

 we are put in possession of a knowledge of the causes from which 

 it may proceed. I mentioned swelling or compression of the 

 hepatic duct as one, in speaking of it as a symptom of hepatitis ; * 

 and probably this is the most common one. In the human sub- 

 ject, it frequently arises from obstruction of the ducts, either 

 from collected or concreted bile in them, to which the name of 

 biliary calculi is given ; or it may be the effect of spasm in the 

 ducts, or in that part of the duodenum f where they terminate ; 

 but I am not aware that cases of this kind have occurred in 

 veterinary practice ; and one reason, I repeat, is obvious. The 

 horse has but a single duct, through which the bile flows as fast 

 as it is secreted ; it has no retrograde course to take, no recepta- 

 cle to collect in and to concrete into gall stones ; and, as a proof 

 that this is one reason, dogs, and such other of our domestic 

 quadrupeds as have gall bladders, are all of them much oftener 

 jaundiced than horses. People who lead sedentary lives, such as 

 corpulent subjects and women, are predisposed to jaundice ; in 

 them the bile often grows inspissated % in its ducts, and biliary 

 calculi are now and then detected in the stools : this is a cause 



* Inflammation of the liver. 



t The first portion of the intestines ; sometimes called the second stomach. 

 In cattle it is known as the fourth stomach. 

 1 Thickened. 



