My boy's on a special diet of James Senior Light (though am a bit confused about the carb content - 51% rice & oats) - he gets about 200g per day in small portions and half a tin of Chappie (I swear by it... I think its best tinned dog food out there) and sometimes steamed carrots mixed in and the odd raw bone. He's looking great!

Found this...

Butchers Tripe - Review - PERSONALLY, I'D RATHER EAT A DEAD BUTCHER