You know, he was on the truck for days next to a white pony. Hopefully that was it. He was wormed when he came off the truck but I maybe I should do it again in a few weeks? I'm a bit of a stresshead so here's hoping it's just him grooming the white pony obvessively. She did sent me lots of photos of him and his old paddock buddy constantly grooming eachother before I bought him.