The short answer
Yes — plain oats are a safe, wholesome treat.
Why
Plain rolled or porridge oats are a good source of slow-release energy and fibre. Serve them dry, or cooked with water only — never with milk, sugar or salt.
How to feed it
Offer a small sprinkle of dry oats, or a little plain cooked oatmeal, cooled.
How much & how often
A small amount a few times a week.