Vitamins and minerals – when and why should we supplement?

A balanced diet containing adequate quantities of vitamins and minerals is essential for our horses, just as it is for us. In a ‘natural’ environment horses and ponies fulfill their nutritional requirements solely by grazing grass and other herbage, so why would we need to worry about vitamins and minerals in a domestic environment?

The answer is that most pastures contain a lower variety of grasses and other plants than would be found in a wild environment. In addition, different soils contain different quantities of certain vitamins and minerals. This is not a problem if the horse is roaming over a large area comprising many soil types, but it can have a real nutritional impact on horses grazing more restricted areas such as fenced fields and paddocks.

In addition, many horses are stabled and fed hay or haylage rather than grass, particularly during the winter months. The vitamin and mineral content of the grass is further reduced when it is processed into hay or haylage.

Most complete hard feeds are balanced in terms of vitamin and mineral content, but only if they are fed at the recommended quantity. In practice, many owners feed lower quantities of hard feed than this, particularly in horses that are prone to weight gain or ‘fizzing up’. Horses and ponies kept on a restricted diet, for example due to laminitis, are particularly at risk of vitamin and mineral deficiency.

In addition, horses in hard work may have especially high requirements for certain vitamins and minerals in order to optimise immune function, cell turnover and performance.