Hilbert had a slight, light haze on x-ray so needed some follow-up urinalysis work to see if it was just an artifact or if he is starting bladder sludge. The results from the follow-up tests could not be better! His pH was not too low, he concentrated not too much and not too little, etc. Morney was perfect on x-ray and her urine pH tests at home haven't been too low, though for a while Hilbert's remained on the low side. So, we have two ferrets here who got cystine stones on higher protein diets but after almost a year are not getting them on the more standard 35% protein diets. The number of ferrets who do this is unknown, but we have heard of some who responded just the same way, as well as hearing of two who needed medical intervention. There is a chance that this is genetic. Many, many generations of U.S. ferrets have eaten 35% protein diets so the ones who would have died off early on diets with a higher protein level similar to wild diets would have survived and procreated just fine. Ferrets are not the only members of Carnivora in which some members have this vulnerability, for example it is documented multiple breeds of dogs and in at least one species of wolf. There is a study of these ferrets going on. This information is asked to be shared with your vets, please: > Study Coordinator: Michelle Hawkins VMD Dipl. ABVP (Avian Practice) > Companion Avian and Exotic Pet Service > VM: Medicine and Epidemiology > 2108 Tupper Hall > University of CA, Davis > Davis, CA 95616 > 530.752.1363 (ph) > [log in to unmask] Some cardiomyopathy info: http://www.afip.org/vetpath/WSC/wsc04/04wsc08.pdf [Posted in FML issue 4847]