When veterinarians evaluate animals presented with evidence of liver disease, a key question to be answered is whether or not the underlying problem is interference with the normal handling of bile or damage to the liver itself. Very often, they address this question by measuring serum concentrations of one or more of the five enzymes that commonly are associated with the liver. This interactive book presents information about each of these enzymes, their location, when they enter the circulation, and how they can be used to evaluate the progress of liver disease in different animal species.