Remember that wild relatives tend to stash food for multiple meals.
 
I have long standing permission from Dr. Bruce Williams, veterinary
pathologist and ferret expert to send this segment when this topic, ALT
levels, or other related things come up.  It is highly informative:
 
http://www.afip.org/ferrets/Clin_Path/ClinPath.html
 
>Probably the most common misinterpretation that I see on a routine basis
>is in the area of hepatic enzymes.  Remember, that the ferret, being by
>nature an obligate carnivore, has an extremely short digestive tract,
>and requires meals as often as every four to six hours.  Should food not
>be available, it possesses the ability to quickly mobilize peripheral
>fat stores in order to meet energy requirements.  When this physiologic
>mechanism is activated, the liver is literally flooded with fat, which
>results in hepatocellular swelling which may be marked.  The result of
>this swelling is the leakage of membrane enzymes such as alanine
>aminotransferase, and as the hepatocellular swelling increases,
>occlusion of bile canaliculi occurs, resulting, over time, in elevation
>of alkaline phosphatase.
>
>In conjunction with this physiologic change, elevations of ALT up to
>800 mg/dl can be seen, and alkaline  phosphatase up to approximately
>100 mg/dl.  This often causes confusion to practitioners, who render an
>erroneous diagnosis of unspecified hepatic disease.  However, hepatic
>disease is quite uncommon in this species; the most common cause of true
>hepatic disease in the ferret is neoplasia, with lymphosarcoma causing
>95% of cases.  Rarely bacterial infections of the liver or biliary tree
>may be seen.
>
>The diagnosis of hepatic disease in the ferret must be based not only on
>ALT and alkaline phosphatase, but other clinical indicators in the CBC
>and chem panel.  Clinical elevation of icterus or an elevated bilirubin
>is an excellent indicatior of primary hepatic disease, or concomitant
>leukocytosis or pyrexia may lend additional credence to a diagnosis of
>primary hepatic disease.
 
It's a really marvelous article.
[Posted in FML issue 4658]