We may be lucky or whatever. However, our adults, yearlings, and weanlings get horse quality bermudagrass hay (about 12% protein) and a HIGH quality molasses/mineral tub specially for horses which retails for about $45. a 50# bucket currently. Lots of minerals, vitamins, antioxidants in the formula. We also use some "pelleted" feed (occasionally for special situations) that is 15% protein (alfalfa based): Bio Remedies "Total Equine". 50# bag retails for about $9.50 a 50# bag currently.
Have had no problems with any of our horses or any age. Their (non-winter) coats are slick & shinny, conformation great, no illnesses. Hoofs maintain great condition. Our one pregnant 26.5 year old TWH mare had some arthritis & nutrition problems when we got her last year. After putting on our feeding program, supplemented with "Nutri-Lix" liquid (1 oz. in feed daily) and 1/8 cup of "Tasco" seaweed product daily, she is in great condition, no observable joint or arthritic problems and is very active for a mare her age.
We don't feed Oats or any of the other "small grains". All of our horses have loafing (run-in) sheds, and 24/7/365 bermudagrass pasture.
For a look at our horses on these hay, feed, mineral products check their photos on our website.
If anyone interested in our sources for the Bio Remedies products, just e-mail or PM me.