Melanie, there is a non-chicken based food available through your
veterinarian from either Hill's or Walthams that is duck based.  We had
one foster ferret that we suspected had a food allergy to chicken and
ended up putting him on this diet for a while.  It seemed to do the trick
initially and ended the diarrhea, but he had too many other problems
going on at the same time and so we ended up losing him to his other
ailments.  It is a feline hypoallergenic food that is available in both
canned and dry formulas.
 
betty and her blur o'fur
for the love of ferrets...
[Posted in FML issue 4140]