How important is Protein in a horse diet?
According to the National Research Council (NRC) nutrition tables, horses require only 7.5 to 12 percent protein as an adult. The lowest percent of protein in commercial feed available is 10 percent, and it is common to see protein levels in the feed of 14 to 16 percent. Since horses are made to live primarily on roughage, there is no physiological reason to have protein levels so high. High performance horses usually eat more grain so, if they need slightly more protein, they will usually get it from the increase in volume. Certain horses have a greater requirement for protein and can benefit from the addition of protein to their diet; that must be decided on an individual basis. When feeding excess protein, it needs to be treated as nitrates since protein is just one form of nitrogen, and nitrates can be toxic. Young animals digest protein well. Some can tolerate more protein and can use it to grow muscle but, many breeds of easy-keeping horses do poorly on excess amounts of protein
