
No they don't have to be removed. Many dogs do have them removed (my own included) because they
can be a right nuisance, getting caught and damaging people, clothing and not least hurting the dog. That said, some dogs never have any trouble from them. If they are going to be removed, it is usually done when the pup is about 3 days old, so your pup being the age s/he is (sorry, I can't remember if you have a dog or bitch) I would leave well alone unless they cause trouble, because it would involve a general anaesthetic, stitches, bandaging etc. Just make sure you keep the nails well trimmed when you do the rest of them (I do my dogs once a week) because they don't wear down naturally.
:)