The 2 big things against Proplan Turkey and Barley are low protein (31%) and low fat (14%). Have you tried Hill's Prescription Diet feline d/d or Eukanuba's response feline lamb and barley? The d/d canned food has a dry matter protein of 39% and a fat 28% level. It is a lamb and rice product. The Eukanuba can lamb and barley has a dry matter protein level of 41% and a fat level of 27%. Both of these are closer to what you want for a ferret food without having chicken or poultry as the protein source. Food for thought, Jerry Murray, DVM [Posted in FML issue 3420]