Question
To complement an all-forage diet (grass hay and pasture grass), would I use Micro-Max or All-Phase for my two-year-old Arabian mare?
Answer
For a young horse such as your mare, choose All-Phase, as it contains the protein necessary to support healthy growth.
While horses achieve most of their growth (height) by the time they are two years old, they are far from physically mature. Most will become wider and more muscular with age.
Micro-Max is an excellent source of vitamins and minerals for mature horses on all-forage diets, but All-Phase is the right choice for young horses, especially if you plan on starting a low-level structured exercise program with her.