It depends on what you're feeding. Generally, a horse only need a overall vit/min supplement if it's not getting any fortified feed (sweet feed or pelleted feeds). Or the horse is getting 50% or less of the recommended quantity of a fortified feed.
If the horse is getting some feed, but not much, and is on Grass or Timothy hay, I like
Select II,
Grand Vite,
Accel, or
Augment, in that order.
If the horse is getting only beet pulp, unfortified grains, or hay pellets/cubes as their concentrate, I like Uckele
Equi-Base Grass, SmartPak's
Smart Vite Maintenance Grass, LinPro,
Just Add Oats, or
Equine Challange, in that order.
