black labrador baylie swapped sweet treats and processed dog food for a diet of free range raw meat , offal and bones in his quest to lose weight .
his owners , margaret and patrick evans from leeds , say he 's now ` a different dog ' after losing a stone and a half in eight weeks through the doggy diet - the weight of four chihuahuas .
the plan was devised by vicky marshall , who runs a natural dog food company and realised that none of her 5,000 customers ' dogs .