The very first time you went near a horse, you probably started hearing The Rules—don't walk behind a horse, don’t run anywhere, always feed treats on your flat palm with fingers outstretched, and so on. The rules of feeding are the big ones. Remember them, and you’ll have a good foundation upon which to build your overall horse care.

1. Provide plenty of roughage

Many pleasure and trail horses don't need grain: good-quality hay or pasture is sufficient. If hay isn’t enough, grain can be added, but the bulk of a horse’s calories should always come from roughage.

Horses are meant to eat roughage, and their digestive system is designed to use the nutrition in grassy stalks. A horse should eat one to two percent of his body weight in roughage every day.

Horses who spend much of their time in stalls aren’t doing much grazing, but their natural feeding patterns can be replicated by keeping hay in front of them for most of the day. They can nibble at it for a while, take a break and snooze for a while, and then come back to it, keeping some roughage constantly moving through their systems.

2. Feed grain in small amounts and often

If you feed your horse grain, give it in multiple smaller meals rather than one large one. Most horses are given grain twice a day for the convenience of their human caretakers. If for some reason you must give your horse a large quantity of grain, consider an additional lunchtime feeding. Small, frequent meals not only are more natural for the horse, but they also allow the horse to better digest and use his food. When a horse is fed too much at once, the food isn't digested as effectively.

3. Feed according to the horse's needs

• Each horse is an individual and has different needs. Two major factors for deciding how much your horse needs to eat are her size and the amount of work she does.
• Consider the amount of hay or pasture your horse gets: Horses who are grazing on good pasture the majority of the day don’t need much hay, if any. Horses who don’t get much turnout or aren't on good pasture will need more hay, whether they are inside or out.
• During winter or drought, supplement pasture grazing with hay. When the grass is thick and lush, you can cut back or eliminate hay rations completely, depending on how much pasture is available.
• With grain, less is always more, so start with the minimum and adjust it upward if necessary. With a little bit of tweaking, you’ll find the right balance of pasture, hay, and grain for your particular horse’s needs.
• If the amount of work your horse is doing changes, be sure to adjust her food ration.

4. Change feed and feed schedules gradually

Whenever you make a change to your horse’s ration, whether it’s increasing or decreasing the amount or changing to a new kind of feed, make the change incrementally. Sudden differences in the amount or type of feed can lead to colic or founder.

If you're changing the amount of feed, increase or decrease each meal a little at a time, over several weeks if possible. One method for changing the type of feed is to replace 25% percent of the current food with the new food every two days, so that in six days the horse is eating l00% percent of the new food.