Howdy. I posted a while back about Cassie having a slight build-up of a reddish residue around her vulva. I had my vet run just about every test possible (I'm a little paranoid since I lost Bud in December). Just about everything checked out fine; blood tests didn't indicate any infection, which was my first thought. I even had X-rays taken (boy are their bones ever thin!). The only thing that was unusual was that her urine was a little less acidic than most ferrets he had seen, and there were some crystals in it. He said these might be irritating her urinary tract. He asked if I had changed foods recently, and (doh!) yes I have. I've been buying ANF Tami for a couple of years, but late last year I was having trouble finding it. I started trying a number of different foods, all of which appeared to be of roughly equal quality based on the ingredients and nutrient breakdown. I finally settled on Nutrience, as it was the one the ferrets liked best. Anyway, after this Bud got sick and passed away, so when Cassie started having her trouble I didn't even think about having changed foods a few months ago. The vet gave me a couple of weeks worth of Hills prescription diet C/D for Cassie, which was supposed to encourage more acidic urine and discourage the formation of any solids (crystals, stones) in the urine. I had her back yesterday for a follow-up urinalysis, and her urine was nicely acidic and had no solids present. I haven't seen any residue around her vulva anymore either. My vet said there were probably a number of commercial brands of food that would accomplish the same effect as the prescription diet. He gave me a list of the ingredients and content breakdown, and said to look for a brand that was similar. He said in particular that ash should be kept low, as it may produce some of the solids in an animal that is prone to them. He also said to try to match the level of magnesium, and the ratio of protein to carbohydrate. I looked around, and they all looked pretty similar (though not all brands listed all the ingredients I was trying to match). The closest brand I found in terms of ash was Nutrience at 5.5% (the hills prescription was 4.5%). But Nutrience was the brand that seemed to cause the problem in the first place. I was wondering if anyone out there knows of specific brands which encourage more acidic urine, other than prescription brands. Although if need be I can always put them on the prescription brand permanently; my vet says it is a balanced diet and fine for long term use. And it's about the same price as Iams. -- John Rosloot, Caregiver to Cassidy and Sammy With loving memories of my dear departed Buddy Technical analyst, Dept. of Computer Science, University of Regina Regina, Saskatchewan, Canada http://www.cs.uregina.ca/~john/ferrets.html [log in to unmask] [Posted in FML issue 1480]