What happened to Timber's tail???

Something has happened to Timber's curly-q tail

Since Timber was a puppy, his tail has always curled over...almost like a pig's.

But, then today after their walk, Jamie commented on how it wasn't curling anymore.
Pictures taken today...
Poor buddy, he just doesn't look the same without his curly-q!
And...well, Timber, he just doesn't want to talk about it! :)