I just wanted to out one little thing. There are veins that supply the skin and they are very tiny. Sometimes, when the skin is punctured by a needle, the vein is also broken. It is referred to as a skin bleeder. Most animals do not seem to have anymore pain related to a vaccine which results in a little skin bleeder than any other vaccine. If your ferrets play like mine do, I would think it was very unlikely that a tiny needle hurt them very much. Dooks, Erica Buster & Milos [Posted in FML issue 4618]