I don't think adding oats to a duckling feed is a good idea.@KikisGirls has a feed comparison chart which should help.
Also you should be able to get a big bag of oats at your feed store as opposed to rolled oats from the grocery store. You'll get more bang for your buck. Several brands carry them. Something like this...
https://www.murdochs.com/products/l...urpose-feed/country-feeds-steam-crimped-oats/
