Today on the program I am going to talk about oats and feeding oats to horses. In the past, oats were fed exclusively to horses for many years, and most of those horses did very well. However, Dr. Tina Anderson is a nutritionist with Purina and has written a column about oats in a recent Purina newsletter. She indicates oats can be a good ingredient and are palatable but should not be used as a stand-alone ration. Oats are moderate in protein, high in starch, and low in many vitamins and minerals. Oats can certainly be a problem for horses that tend to gain weight, especially those with equine metabolic syndrome and Cushing's disease. Also, Dr. Anderson indicates that oats have a calcium:phosphorus ratio that is inverted, which means the amount of calcium is lower than that of phosphorus, and equine rations require the calcium to be higher than phosphorus. This ratio is really important in young, growing horses.
In my experience, the calcium is usually not that much lower than phosphorus and in many cases, the calcium:phosphorus ratio is equal in oats. However, the calcium is still lower than we would like to see. Of course, we also must consider the other parts of the ration and not just the oats. All horses are also either on pasture or hay, and this must be considered when analyzing a ration. For example, alfalfa is high in calcium while Bermuda grass hay is low in calcium. So you can't just look at one ingredient such as oats when determining an appropriate ration because although oats has some disadvantages, it may be an appropriate ration in adult horses depending on the pasture or type of hay available.