A 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: http://www.hcusupport.com/diet.htm 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. Sukie (not a vet) Ferrets make the world a game. Recommended ferret health links: http://pets.groups.yahoo.com/group/ferrethealth/ http://ferrethealth.org/archive/ http://www.miamiferret.org/ http://www.ferrethealth.msu.edu/ http://www.ferretcongress.org/ http://www.trifl.org/index.shtml http://homepage.mac.com/sukie/sukiesferretlinks.html all ferret topics: http://listserv.ferretmailinglist.org/archives/ferret-search.html "All hail the procrastinators for they shall rule the world tomorrow." (2010, Steve Crandall) A nation is as free as the least within it. [Posted in FML 7703]