Dogs do this out of instinct from when they were wild. It's usually when they smell something on the ground they roll around in it to mask their own scent. They would want to do this if they were hunting in the wild so prey wouldn't smell them approaching.
And isn't it amazing that they start the rolling JUST after being groomed? They really do not like to be clean.
Last night little foster girl Kelsey found a dead rabbit in the garden. Before I could get it, she was rolling and yipping and having a wonderful time. Needless to say, her next bit of fun was in the sink. ;-)
Micah does the same thing after I give her a bath. she makes her goblin noises too as she runs around the house rubbing on things. She always manages to end up on the bed though, so i always have the change the sheets after i give her a bath, or else i go to bed and smell wet dog all night. I swear she does it just to get back at me since she hates bathes.
According to some "experts", dogs roll to put their scent on the ground. Remember that scent is their telephone and newspaper. At the tree, "Um, I remember this guy. He's the Lab up the street". But then, none of the experts agree, and the Corgis aren't telling!
We have two Corgi's and each of them have their part of the yard that they like to roll in. For the boy it is a sport with no grass and a little shade. He just lays down and then rolls over. For the girl it is kind of nose first on one side sliding down along the right side until she can rollover and the the fun begins. She like the grass close to the house. So each has their own way to roll in the yard...
I have noticed they like to roll more a couple of days after the bath....
I am so glad I found this website. I always just that it was our Corgi with her little quirks. Every morning after she eats, she takes a running leap and rolls on her back on the carpet. She does the chinchilla roll for a few minutes. She also finds things outside all the time.
One night we were outside and she was in the yard and she was being awfully quiet. We found her rolling. She came in the house and it was the nastiest smell. We found that she had rolled in dead baby mice that had rotted. We didn't know they were there. Immediately got her in the tub and gave her a bath.
She rolls all the time....they are so funny with that. She has even taught our GSP how to do it.