Woah! of course it need to be operated ASAP!! You see Hernias is a problem that could happen to people as well. If you try ask people what is that for human. You as well get the pciture what could happen to your dog! In fact, hernias could make you dog urination problem.
As far as I know, u don't have to necessarily do the operation ASAP like they said. I have a small toy dog that had dishernia on the tummy. My vet doesn't think it's an urgent problem although fixing it will be best. One thing u can try is rub 2 of ur fingers on the dishernia gently a few minutes, sometimes this will help the wound to close up by itself. If it doesn't work, operation will help. I fixed my dogs by just rubbing my fingers on the hernia. they'll feel uncomfortable but it's worth a shot! :)