Is it normal for a mother dog to bite her 3 day old puppies?
She probably isn't biting them. It is more like she is nipping them. This is normal. This usually occurs as a sign of discipline when the puppies are being rough. The mother dog will tolerate the puppies, but she will control her young when they nurse to hard.
its not recomended. the mother will become worried and begin looking for her puppies everywhere. it wont be a break for her. and the puppies will be whinning constantly for milk. the puppies might also die without food. the mother and pups would probably be okay with an hour or two away from each other