When the sheep eat their late afternoon treat of concentrates they often grab as much as they can and swallow it quickly.  Wiggle is as guilty of this as the next sheep and one of the pellets went down the wrong way.  He was jumping about, shaking his head and choking so Jeremy flipped him onto his back and jerked his rib cage.  Lo and behold the blockage flew out and, after some comforting, he was off eating grass again and back to his usual self.