If you are looking to round out your horse’s forage-only diet, the best bet is a balancer pellet, which will provide the protein, vitamins, and minerals your horse requires for optimal health. An in-depth review of balancer pellets can be found here.

However, balancer pellets often contain soybean meal because it is a common source of high-quality protein. In fact, it may be difficult to find a balancer pellet that does not contain some type of soy. You would have to contact the manufacturer to determine the ingredients of a particular balancer pellet.

In light of that, try a vitamin/mineral supplement such as this, which does not contain soy or flax but will provide your horse with the nutrients it requires.