I have fed Ultium for about a year now. My goal was
to keep weight on Piper, and to refuel him between and during rides. It has
worked great for that. The only problem we have had with it was that when
you try to make a sloppy mash, it turns into sludge. So I
usually add beet pulp, crimped oats, chopped alfalfa, and another Purina
product " Race Ready" (8% fat) to keep the texture more palatable.
He seems to not like the taste of Ultium alone at rides, but when I add the
other stuff, he eats it fine. But in true endurance horse fashion, his
favorite feed at vet checks is "SOH Brand" (Some Other
Horses)
As far as making him crazy, It doesn't. We
rode Tevis and the OD 100 with only a cheap nylon halter for headgear, ( no bit
or bridle) as well as just about every other ride we entered this
year. He is always mellow and controlled at the start.