Bob I am sure you mean well but I wonder if you could tell me (us) exactly what these other methods are that you mentioned in your post. I don't know about anyone else but I don't have those sources that you mentioned, so have no idea of what methods they are. I raise exotic birds & use the clipped nail method for DNA purposes. To surgically sex a bird, it has to be given anesthesia & then a small opening is cut in the side of the bird & a probe is put in. Although my vet uses the safest anesthesia on the market last year he lost his own bird who he put under to do a routine nail clip, & exam on. It had a bad reaction to the anesthesia that it hadn't had before. On some ferrets it is hard to find a vein. Heck I know from a lot of experience that it sometimes hard to find a vein in a human & have gone through exploratory vein searches myself. And I am almost always told that I have "wonderful" veins. I was not happy that someone had a hard time finding my veins, it hurts to get poked by the needle. I am sure it must hurt for a minute or two, getting the nail clipped but I don't think it is that bad. You clip the end of the nail down to where the vein starts, not way down. The blood flow almost always stops right away with a little pressure on the nail & if it doesn't you can use corn starch or flour or nail quick to stop the bleeding. For a fuzzy a taste if Ferretone or Ferretvite or a treat & a hug & rub & the ferret won't even remember it. I'm glad you & your vet are cautious. And whatever works for you & yours is great. However it is my opinion that the nail clip is the fastest & best way to go. Lynn [Posted in FML issue 2920]