Senior Feed for a Horse Prone to Founder: What to Check

Last updated: September 1, 2026

By: Miles HenryFact Checked

Are you feeding – or thinking about switching to – a senior feed and worried it could cause founder?

A horse can founder while eating senior feed, but the word “senior” does not mean the formula is automatically safe for a horse with a founder history, insulin dysregulation, PPID, obesity, or another laminitis risk factor. What matters is the specific feed’s sugar and starch, the feeding amount, the forage, and the horse’s underlying condition.

Senior feed can be a real benefit when an older horse has worn teeth, trouble chewing hay, or difficulty maintaining weight. But it is not the right answer for every horse. I will walk you through the feed-label details I check, how I think about hay and pasture, and when it is time to bring in the veterinarian and farrier before changing the ration.

How to Read a Feed Tag

NSC stands for non-structural carbohydrates. On a feed tag, the most useful numbers to ask for are the separate sugar and starch percentages. In forage reports, you may also see WSC (water-soluble carbohydrates), ESC (ethanol-soluble carbohydrates), and fructans. Those terms are related, but they are not always calculated or reported the same way, so don’t assume every company uses “NSC” in exactly the same sense.

A feed can be marketed as “low sugar” and still contain enough starch to be a poor fit for a horse with insulin dysregulation or a laminitis history. An ingredient list alone cannot tell you the actual sugar-and-starch level, so request current information from the manufacturer for the exact product you are considering. When you have the numbers, here is what I look for:

• The separate sugar percentage and starch percentage, preferably on a dry-matter basis
• How the manufacturer calculates any listed NSC figure
• The amount fed per day and per meal – a lower-NSC feed can still add a meaningful carbohydrate load when fed in large amounts
• Whether the product is a complete feed or a concentrate meant to be fed with hay or pasture
• Whether the manufacturer can provide current product-specific numbers rather than a broad marketing claim

For horses with insulin dysregulation, EMS, PPID-associated laminitis, or a relevant laminitis history, a common veterinary target is forage that tests below about 10% NSC on a dry-matter basis. Some feeding plans use a 10 to 12% target range for low-sugar, low-starch feeds, but the right target depends on the horse’s insulin response, body condition, pasture access, and complete ration. Treat any number on a feed tag as part of a veterinarian-guided feeding plan – not as a safety guarantee on its own.

The bag is only one part of the answer. A horse can eat a low-starch concentrate and still have an unsuitable overall ration if its hay, pasture, treats, meal size, body condition, or underlying endocrine disease are not accounted for. With a horse that has foundered before, I want the veterinarian, farrier, forage, and concentrate all working in the same direction – not just a different feed in the bucket.

A forage analysis is the best way to know the sugar-and-starch content of the hay you are actually feeding. If testing is not practical, soaking hay in cold water can reduce water-soluble carbohydrates, but the result varies with water temperature, soaking time, and the hay itself. Soaking can also leach some minerals and dry matter, so it is best viewed as a management tool – not a substitute for testing and a sound plan for a genuinely high-risk horse. Dispose of soak water where horses and other animals cannot reach it.

What I Look for in Feed for a Founder-Prone Horse

This is the practical order I actually work through, rather than reaching straight for a specific bag or brand:

1. Forage first. Appropriately selected forage – often grass hay – should usually form the base of the ration. I don’t assume any particular hay is low in sugar and starch just because of its type; if the horse is high-risk, testing matters more than the label “grass” or “alfalfa.”
2. Know the forage, especially with insulin dysregulation. A forage analysis is the best way to actually know the sugar-and-starch content of the hay you’re feeding – general averages by hay type can’t tell you what’s in your specific cutting. Work with your vet or an equine nutritionist to interpret the results and decide whether soaking or a different forage source is warranted.
3. Keep dietary NSC controlled, not just the word “senior” satisfied. Covered in detail below – this is where most owners get tripped up.
4. Don’t feed more calories than the horse needs, especially if it’s overweight or insulin resistant. Extra calories from a “safe” feed are still extra calories.
5. If the horse can’t eat enough forage because of its teeth, that’s where a properly formulated complete feed or a soaked forage replacement becomes genuinely important – but confirm the specific product’s numbers rather than assuming any complete feed works.
6. If the horse is losing weight, don’t automatically reach for more grain or a higher-starch feed. Look at the whole picture first – teeth, forage intake, parasite control, pain, and metabolic status – before assuming the fix is simply more calories.

When Does a Founder-Prone Horse Need Senior Feed?

A horse does not need senior feed simply because it has reached a certain birthday. We owned a barrel horse that was still performing better at 22 than at 11 on a regular diet, while other horses we have known began declining much earlier and truly needed softer, more digestible feed. For a founder-prone horse, the question is not “Is my horse old enough for senior feed?” It is “Can this horse still chew and use enough forage, hold appropriate condition, and stay on a ration that does not worsen its laminitis risk?”

Unexplained weight loss, declining topline, quidding, hay left in the feeder, or trouble maintaining condition deserves a veterinary look before you assume the horse is simply getting old. Dental disease, PPID, pain, parasites, digestive disease, underfeeding, and reduced muscle mass can look much the same from across the stall door, but they do not all call for the same feeding answer.

Not every senior feed is a complete feed, and not every complete feed suits a horse with insulin dysregulation or previous laminitis. Read the manufacturer’s feeding directions to learn whether a formula can replace part or all of the forage requirement, then request current sugar-and-starch information for that product. For a closer look at the metabolic side of the decision, read my guide to managing equine metabolic syndrome in horses. EMS and insulin dysregulation are important drivers of endocrinopathic laminitis, so the underlying condition often matters as much as the concentrate in the bucket.

If a Founder-Prone Senior Is Losing Weight

A thin senior horse does not automatically need more grain. For a horse with a laminitis history, EMS, PPID, or insulin dysregulation, simply moving to a higher-starch feed to add weight can create a new problem. Before increasing concentrate, I would first make sure the horse can chew and use its forage, review the veterinarian-directed parasite-control plan, look for pain or dental problems, and ask whether PPID or insulin dysregulation is affecting the horse’s condition.

Once the cause of weight loss is understood, a senior feed, complete feed, soaked hay product, added fat, or highly digestible fiber may be part of the solution. Beet pulp is one example of a digestible-fiber ingredient commonly used in horse diets, but it is only one piece of the ration. My guide to feeding beet pulp to horses explains its benefits, limits, and how it fits into a balanced feeding program.

The practical point is simple: check the guaranteed analysis and feeding directions for the exact product. “Senior” does not tell you its sugar-and-starch load, whether it replaces forage, or whether it provides enough calories at a safe feeding rate for your individual horse.

Before Changing Feed for a Founder-Prone Senior

Changing feed is a process, not an event. Before I switch a founder-prone senior to a new ration, I work through this checklist:

FAQs

While I have over 30 years of experience in horse care and racing, I’m not a veterinarian or a certified farrier. Laminitis is a complex clinical condition, and the strategies discussed here are based on industry research and personal experience – they should only be implemented under the guidance of your equine health team. This page may contain affiliate links where I earn a small commission at no extra cost to you.