Licking the urine to get the sugar makes good sense.  In comparing this
to humans, you can "dipstick" a human diabetics urine & find sugar, test
their blood & find their blood sugar level.  In this way you monitor how
well the insulin dosage is working to control the human's diabetes.  OR
how well the human is controlling their desire for sugar or is staying on
their diabetic diet!!!!!  But, "spilling" of sugar into the urine is also
a sign that the kidneys aren't handling the sugar.
 
And yes, the ferret could also be looking for minerals.  When a human
has "pica" a desire to eat NONFOOD substances, they are often missing
something from their diet.  They could especially be anemic - low iron
in the blood.  And the "pica" will make it worse, making them crave the
nonfood substance more.
 
But then, licking urine could be harmless.  I don't do it though.
 
Leila E Marcial, RN, CNM
mom to 2 male humans - 1 a soldier & 1 a soccer player
mom to 2 male fuzzbutts - Rocky & Weasle
[Posted in FML issue 4333]