So my rabbit usually isn't the cuddly type, but today he let me give him light scratches on the back. When I moved down and gave him scratches on his side (right by the ribs) he turned his head back and bobbed it up and down as if he was grooming the air. He didn't seem to be hurting and after about 10 seconds he just kinda moved on and continued as before. He's done this twice today when I scratched him there and I'm wondering what it is. Can rabbits be ticklish?