Robert since your dog is not used to rotating dog foods I wouldn’t recommend doing that. However all the foods you mentioned seem good, what ever you go with please do it very slowly. He is older and needs more time to adjust to it. If you find one of them he likes and does well on than leave him on that. Some people here change diet a lot but I don’t recommend you to do that, you could make him sick. So find one and stick with it. Also what ever protein he was eating with Orjien use the same protein in the new food. As far as which one I don’t know. Maybe try Natures Logic.
