Janet-
  I'm forwarding some info I have in my files that someone here on the 
digest posted a while ago about colored urine:
  I'm sharing with the lists some information provided by my vet.  I 
know this 
question has come up a number of times -- both from stone-piggy and 
non-stone-piggy owners. Hope this is helpful to anyone concerned about 
this 
issue. His reply about dark-colored urine is below:

GP's normally have a lot of crystals in there urine as a reflexion of
calcium content and this can make it look colored when combined with
natural pigments in their food, usually the color is yellow to a tan or
orange color, the tan/orange color is sometimes mistaken for blood,
especially when it is seen already dry on bleached paper or paper towel
material as the rxn with these materials can make it look a bit more
red.  The colors are not always just a factor of the foods they are
eating although some foods like carrots can make a orange urine color.
If I remember correctly bacterial processing of the food in the GI 
tract
can produce various pigments that can then be absorbed and secreted,
this can explain changes in pigmentation when the food does not change.
Sometimes owners report changes in urine color after antibiotic
treatment is started or finished.


~Jaime, Molly, Radar, Grumpy Carl, & Albert always in our hearts~
http://www.piggiepages1.blinkz.com/ 



