This is what I base all my feeding around besides my forage.
Equine Supplement-Triple Crown Pelleted 30% Equine Supplement
A ration balancer is just a name for a nutrient dense feed that delivers all the nutrients a horse on a forage based diet needs without alot of calories and sugars.
My Sr feed is not grain based like a traditional feed you might think of with corn and oats etc. I only use this when I need to add calories as it can be percentaged easily with my 30% balancer and not throw levels off. I try to keep all my horses on a low non structural carbohydrate program. Grains are usually quite high in those as a rule. Im not opposed to oats. I have fed them before but had to still buy a balancer to complete a nutrient profile.
Here is its page with ingredient listing.
Senior Horse Feed | Triple Crown Senior Horse Feed Formula Helps Keep Older Horses Healthier
I agree about having grains in the poo to encourage the birds to spread it. Sure helps with flies.