[ This and other Dr. Williams' posts reformatted but otherwise unchanged. BIG ] To David Childress: The birth defect that you see in your ferret, a lack of a toe, appears to be fairly common in ferrets. Absence of toes or extra toes is very common in a number of species, especially cats. There is also truth to the idea that if your pet has one birth defect, the chances are much greater that another, or multiple ones are present, and may show up in later life. Renal cysts and ectopic adrenal tissue (or adrrenal tissue scattered throughout the abdomen are very common defects that often show up as incidental findings at ferret necropsy. Has anyone tried to make a correlation with genetics? No, I don't think so yet. To do that would require establishing a colony of ferrets with a particular defect and raising multiple generations with no outside bloodlines comng in. The big companies, which are best suited for this, don't really care to, because genetically inferior pets don't sell. Same deal with breeders. I don't think that one missing toe is a big deal. It may have been lost shortly after birth, also. I doubt it signifies the presence of other major defects. Generally major defects are present together - in an article I wrote several years ago on a variation of spina bifida in a litter of ferrets, this change was also accompanied by lack of one of the kidneys. Those are two big defects. You have one small defects. Chances are, if you have other defects, they are equally as small. Bruce Williams [log in to unmask] (BACK on line!!!) [Posted in FML issue 1065]