Hi has any one thought of trying the herb Slippery Elm...it is very good for digestion and can be added to their food....just a thought..:0)

Yes Jennie we have tried slippery elm :). We have him on a fish hypoallergenic diet and it does have herbs, remedies to help with digestion. He also gets organ meat. He can't manage anything different and through the years this is the best diet that suits him. 

Sorry to hear all that must be terribly worrying for you and sounds like you've spent alot of time (and money i guess) trying to sort it out best wishes to poor little Rosco at least he has an owner that is willing to try lots of alternatives and not just conventional meds