Ok so we have picked up a skinny dog and by skinny I mean ribs and back bone showing, he has been to the vet and all checked out so he is healthy but I am wanting to put weight on him. Would a high fat diet do it? We will be switching him to RAW so can he gain weight with RAW? I have never had to get a dog to gain weight so when we fed RAW it was pretty easy to maintain the dogs weight. If RAW will do the trick what is the best foods for gaining weight.