Probably the easiest thing to do is to buy a certified organic non-GMO version of “cheerios”. You could google something like “organic versions of Cheerios”. They *should* have less pesticides than conventional cereals.
You could also add a little straight organic non-GMO oatmeal and skip the processed cereal, since dogs don’t really need sugar.
If this is a matter of fiber supplementation (and not something specific to oats), and you’re uneasy even about organic oats, you could try a different source of fiber. You could ask your vet what type of fiber your dog needs, how much, and look for something that supplies it.
Sometimes you get worse stool until you figure out the right balance of fibers and the quantities. . I’d Start with small amounts and slowly adjust.
These are just a few thoughts, hope it helps! Good luck.
