My ten month old cat has a very sensitive stomach, so I have started using grain-free, limited ingredient diet, canned food for him. I am wondering, however, if i need to stick to one specific brand or one specific flavor. I have been rotating Natural Balance Limited Ingredient (chicken, salmon, duck, and venison), Nature’s Variety Limited Ingredient (Turkey, Lamb, Duck), and Royal Canin Selected Protein (Venison, Duck). Is it okay for me to feed him a variety of proteins and brands, as long as the diet is limited ingredient and grain-free, or do I need to stick to only one brand? And if so, should I only stick to one or two proteins, or is it okay to mix it up? Thanks SO MUCH for your help!