The dog is trying to expel the contents of the anal glands which are located at the base of its tail. Sometimes they need help to get them emptied so they scoot across the ground. Groomers take care of expelling the glands as part of the service they provide.
I don’t know how to do it. I don’t want to learn how to do it. If you want to learn, you can ask the groomer or your veterinarian to show you.
Or you can tip the groomer at your regular appointments to become a favored customer; then if your dog seems to be having a problem, you can ask to bring it in for an emergency emptying.
If this doesn’t take care of the problem, the dog may have worms. You should alert your veterinarian who will probably want you to bring in a fresh stool sample in order to identify the exact parasite so that treatment can be immediately effective.
More email questions:
Why do dogs roll in dead fish and seals along the beach.
I think they are trying to gross us out, but that is just a theory
Does drinking water out of the toilet bowl harmful to a dog?
Probably not. And the dog doesn’t seem to mind people peeing in his water dish.
If a dog licks an open cut, does that help it heal?
No, it’s dog spit, not an antiseptic.