How to Balance a Hay Only Diet for Horses

My horses eat hay pellets (either Bermuda or alfalfa mix) and in the rainy season, 5 acres of weed pasture. What vitamins or minerals should I be supplementing? Kayla

Dear Kayla,

Depending on the age and use of your horses, they are probably not getting all the nutrients they need from a hay-only diet. Even horses grazing 24/7 on high-quality pasture (which it doesn’t sound like yours is) may still require mineral supplementation depending on what part of the country you live.

So at a minimum, consider adding a multi-vitamin/mineral supplement to your horses’ diet that is balanced for the type of forage you’re providing. If you’re giving mostly Bermuda grass hay, then feed a supplement to complete and balance the vitamins and minerals for this type of forage. If you’re giving mostly alfalfa hay, then select a supplement that fills the nutritional gaps for this type of legume forage. When feeding a mix of grass and alfalfa hay, go with a supplement that balances for grass hay unless the mix is more than 50% alfalfa. Also, try to feed the same kind of hay all the time rather than switching back and forth because research has shown there is more digestive upset and risk for colic when forage is changed abruptly than grain. That’s because it’s the bugs in the back that are doing the digesting of the fiber in forages and when the source suddenly changes, they can die off—releasing toxic substances—allowing potentially harmful microbes to build up in numbers.

Another thing to consider is protein. If your horses are adults in little to no work (maintenance), then your hay may be providing enough amino acids to meet their daily requirements. However, when they’re on the weed pasture or if they do more than serve as pasture ornaments, you may want to move up to a ration balancer, which provides vitamins, minerals AND protein.

Salt should always be available, and I’m more of a loose-salt fan than traditional salt block fan because I think horses are more likely to get what they need when they don’t have to lick a rough substance. I like the new smooth, hard rock salts though. Just keep in mind they are mostly sodium chloride and don’t provide enough other minerals to meet your horses’ nutritional needs.