The Different Types of Hay for Horses

Fields of fat, shiny ponies populate my stableyard, prompting visitors to ask what I feed them. When I respond that most of them get nothing but hay, people tend to be shocked. Yet grass – in the form of hay when necessary – is the ideal food for horses when fed correctly. But which hay should you feed your horse? And how?

First, let’s look at the nutrients present in hay. There’s a reason why horses have an insatiable urge to graze. Green grass contains every single type of nutrient that your horse needs except for Vitamin D, which your horse obtains when substances naturally present in his skin react with sunlight. It’s a tailor-made horse feed that rivals even the most scientifically formulated concentrate mix. Horses were designed to eat grass, and in the domestic setting, most of them are still given grass in the form of hay.

Good quality, fresh hay, then, contains all the different nutrients your horse requires:

• Protein – used for growth and repair of tissues
• Carbohydrates – used for energy
• Fats – used to store energy and as insulation against cold
• Vitamins A, B complex, C, and E – used for a variety of metabolic processes
• Minerals, most importantly calcium and phosphorus, which are used predominantly for skeletal growth and maintenance
• Fibre – essential for function of the digestive system

The way in which types of hay differs is generally not in which nutrients they contain, but the proportions in which those nutrients are present. Nutrient density also varies from one cutting to another, so to really balance your horse’s diet, it’s best to have a hay sample tested to ensure you know exactly what’s in it. Many farmers will have this done as a matter of routine to check for quality.

A general baseline to check for hay quality is in the percentage of crude protein. An adult horse in moderate work only needs about 10% protein in his diet, while growing, performance and breeding horses will need more.

There are two major categories of hay in which the different types of hay can be placed: legume hay and grass hay.

Instead of being cut from grass, legume hay is made out of fibrous legumes – members of the pea and bean family. The most common types of legume hay are clover and alfalfa. Alfalfa is an especially popular choice and fed to many horses across the world. It is a very nutrient dense hay, containing up to 15% protein and a high proportion of carbohydrates. It is vitamin-rich and extremely palatable to horses. However, it can be problematic to balance the diet when alfalfa is added. For a start, if fed as the horse’s sole source of roughage, it is much too high in protein for the average horse. This can cause kidney problems as the horse’s body tries to flush out extra protein in the urine. Its calcium: phosphorus ratio is also wildly out of whack, with a huge amount of calcium impeding the absorption of phosphorus. Alfalfa is best fed as a supplement to high quality grass hay to boost protein intake, preferably with bran or a phosphorus supplement to balance the mineral content of the diet.

Clover hay is very similar to alfalfa, with a very high protein content and excellent palatability. Its

Ca:P ratio is also generally unbalanced, but the advantage of clover hay is that clover is usually planted alongside grass and then cut and baled with the grass hay, so the two hays are already mixed. This boosts the quality of a grass hay crop and eliminates the fuss of having to feed two different hays to your horse. However, some sneaky horses will pick out all the clover and leave the grass, so you have to keep a close eye on your horse’s intake.

Grass hays are the most traditionally fed to horses and also the safest food for horses when of good quality. Grass hay most closely mimics the horse’s natural diet of prairie grass, and for easy keepers in light work, it’s all they need to stay fat and happy.

Types of grass hay vary across the world, but in the US, timothy hay is by far the most popular. Good quality timothy is up to 10% protein, which is sufficient for most horses. It is high in fibre and thus optimises the horse’s digestive system while supplying a moderate amount of carbohydrates. Good quality, green timothy hay is also rich in well-balanced vitamins and minerals. Bermuda grass and orchard hays are very similar to timothy hay and can be fed almost interchangeably according to what’s available – and cheaper – in your area. Timothy hay is a safe bet, but almost always more expensive than bermuda grass or orchard hay. The only real disadvantage of these grass hays is that they do not contain enough carbohydrates and protein for performance or breeding horses, so must be supplemented with alfalfa or concentrate feed. Later in the season when the hay has lost its greenness, it may also be low in vitamins and minerals, so a balancer may need to be fed.

Another type of grass hay is oat hay. This hay has a similar protein content to other grass hays, but is significantly higher in carbohydrates. For a skinny horse who needs to pack on some pounds or a performance horse who needs some extra energy, oat hay can be great, but it is disastrous to feed to insulin resistant, overweight, or laminitic horses. It may also cause some horses to become hot and unmanageable to ride.

The best way to choose the perfect hay for your horse is to analyse his dietary requirements and then have the different hays available in your area tested to find the closest match. The most important thing about feeding hay is to always feed enough – your horse needs that fibre to keep his system functioning at its best. It’s best to feed hay ad lib, except to very overweight horses, who should be fed in a slow feeder to ensure they always have access to roughage.