what type of oats should i feed for energy?

[Tacobell]

hi all

my horse is an allergy to barley so i have to be careful in what i feed. i am wanting to add oats to his diet for extra energy. What type would be best as my current feed store sells bruised, crushed and whole oats?

he is currently on simple systems red grass pellets, however he has to eat such large quantities and when soaked this takes up a whole bucket and he ends up leaving half so looking for another altnerative.
I have treated him for ulcers in the past so looking for something low in starch

 

[Carlosmum]

Whole oats will go straight through. The difference between bruised and crushed is the treatment they have had in the mill. Personally I would use crushed, but I am not a feed expert

 

[Gloi]

Oats should be bruised or crushed. Is there a reason he is on massive amounts of grass pellets rather than hay?
What is his background/ health issues apart from ulcers? Is he thin or just not forward going?