Bladder stones and Diet (Zupreem Grain-free)
- Ferret friends:
Today I removed over a hundred bladder stones from a three and a half year old ferret, fortunately before any of them moved into his urethra and caused a blockage. Guess what he'd been eating?
If your answer was Zupreem Grain-free, you've been paying attention.
DO NOT feed Zupreem Grain-free ferret food to your ferrets, please. It has been associated with bladder stone development in many ferrets, and while the cause is not proven, many suspect it to be due to the pea protein in the food.
- As Dr. Ruth pointed out, peas are in question as a food item for ferrets, but they are not alone.The separate archives are down so I am including this past post of mine that I sent after hearing from someone in Britain who mentioned that she is in a relevant field of academics and work. She said that with enough sulphur also present in the food the body can more easily convert methionine into cystine instead of just leaving it as methionine.QUOTEFrom: sukie@...Subject: I learned a mechanism today for peas playing a direct role in cystine uroliths (cystine stones)Date: February 14, 2013 5:03:09 PM ESTA kind researcher in bio sciences taught me today that foods that are high in sulfur, which she says include peas and sweet potatoes, facilitate the body biosynthesizing cysteine. So, beyond pea flour being a useful binder for some of the foods that have very accessible amino acids, and beyond some of those foods having added methionine the peas may be a direct player in the production of cystine uroliths (cystine stones).She gave this site for seeing methionine content and peas are high though not the highest:The body can convert methionine into Cysteine; providing more of what facilitates that conversion is a problem.In that list I see at least one other food item found more and more in ferret foods.END QUOTESo, when evaluating a food option it may pay to see if the food contains ingredients which are high in sulphur (sulfur also an acceptable spelling with one being more American and the other more British) AND ones high in the amino acid, methionine. They do NOT have to be the same ingredient. Two or more ingredients eaten about the same time would be bad, too, if this mechanism is what is happening.It is NOT known how many ferrets have the genetic susceptibility to forming cystine uroliths, though reports of such stones in ferrets increased greatly after high protein foods came out. That is because the urinary system in such individuals allows cystine to precipitate out of the urine if the diet is high in any of four amino acids, the so-called COLA group which stands for Cystine, Ornithine, Lysine, and Arginine. A diet too high in ANY of those amino acids can pose problems for such individuals, so when the susceptible ferrets get too much protein they can wind up in trouble.Add onto that consideration that that body can create amino acids from each other if the right things are available in high enough amounts and you get to why peas apparently pose a risk factor for these genetically susceptible ferrets.A few ferrets who get cystine uroliths (urinary stones) have to have medications that increase the pH of urine, but many thrive just by living on a diet that is kept to no more than 35% protein. We have had two who went on after their surgeries as one year olds for cystine uroliths to live full lives for 6 more years in one case and 7 more for the other if I recall right. We kept their diets to no more than 35% protein, given their histories, made sure they stayed hydrated, and monitored the things like their urine pH for at least the first year. One of the two developed insulinoma but that was very near the end of life. The other never got it. (We normally have about 20% of our ferrets get any of a range of pancreatic diseases in life, with insulinoma being the largest type in that mix.)