Jehovah’s Witnesses: If your son/daughter was bitten by a venomous snake, would you suck the poison out?

I always wondered something kind of similar. You know when you are cutting vegetables and maybe cut your finger how you will automatically put it into your mouth to keep blood going all over the potatoes? I have done it if a towel is not handy (I find it gross so i don't make it habit) and of course, I swallow a tiny bit of blood. Would that be a sin? because in essence I just ate so blood?