First of all, regardless of which hay you feed, if you place it in a slow feeder (or hay net) and allow your horse 24/7 access to hay – you will have a much healthier, happier horse. If you put the right kind of hay in that slow feeder, even obese or laminitic horses will thrive – and yes, I’ve tested this!
So, once you have your slow feeder in place, you need to fill it with the right kind of hay: Unless your horse is doing a lot of exercise, then you’ll want to feed a low starch, low sugar hay. You want the Non-Structural Carbs (NSC) – which is the TOTAL of all sugars and starches – to be lower than 12%. The only way to determine this is by getting your hay tested. Many good hay farmers will get their hay tested at an independent lab and be able to provide you with a report. But if you want to double-check, or do it yourself, here’s how:
Some people think that whether the hay is 1st cut or 2nd cut influences sugar levels – but in fact it is more determined by the type of plant, whether it has bloomed/seeded or not, and the time of day the hay is cut. That’s why you (or your hay company) needs to have the hay analyzed to determine the actual NSC levels.
How hay can affect horses’ teeth
I prefer the first cut of low-sugar hay in slow feeders for my crew. This is because the stalks are coarser and higher in silica; which means the horses naturally ‘file’ their own teeth as they chew. I got Zorra when she was 9 years old and her previous owner told me she must have her teeth filed/floated every year or she would be in pain, or have trouble eating. After 5 years with me – eating low-sugar 1st cut hay, available 24/7 in a slow feeder – Zorra still did not need her teeth floated. In fact, the vet checked a few of my semi-feral horses as well, and all were a-okay. Zorra is now 19 years old and has never needed to have her teeth floated!
See the results of my 7 years of experimenting with different kinds of slow feeders; which ones worked best to prevent tooth and gum damage.
Understanding hay test results
Ok, so once you have your hay test results in hand, here’s a simple outline you can download of what your test results mean. If you want the in-depth analysis, then here’s a 20 minute video that covers every aspect in depth. The most important parts of your hay analysis are:
Dry Matter (DM)– This tells you how much of the sample is left after water is removed. It is the moisture or dry matter content of the sample. Hay will generally be about 89 percent dry matter or greater.
Digestible energy (DE) – This is a measure of the digestible energy in the hay. For a light-working horse, DE should be 20.5 Mcal/day. Hay may have .76 to .94 Mcal/pounds or higher of DE.
Total Digestible Nutrients (TDN) – This is a measure of the total digestible nutrients in the hay or its energy value. TDN may be used in place of DE or offered in addition to DE. It may range from 40 to 55 percent.
Crude Protein (CP)– This is a measure of the protein concentration of the hay and can range from 6 percent to 8 percent in native grass hays to about 15 percent or higher in high quality legume hays.
Neutral Detergent Fiber (NDF) – This is a measure of the plant’s cell wall content, shown as a percent. The higher this is, the less hay the horse will eat.
Acid Detergent Fiber (ADF) – This is a measure of the fiber concentration of the hay, shown as a percent. As ADF increases, digestibility and nutrient availability decreases.
Non-Structural Carbohydrates (NSC) – This is a measure of the non-structural carbohydrates in the feed. If your horse has Cushing’s disease or is prone to colic or laminitis, you want to select hay with a lower NSC value. Timothy and alfalfa hay may have a 15 percent or 20 percent NSC value, respectively. If you want this analysis done, you should check to see if the lab offers it, as it is not a common analysis at this time.
Starch and Sugar – This is a measure of sugars and starches in the feed. You should feed no more than 15 percent of total daily calories from starch and sugar to horses with EPSM (equine polysaccharide storage myopathy) and PSSM (polysaccharide storage myopathy). EPSM is a muscle disease found in over 100 draft breeds that may cause severe weakness and muscle wasting in horses of all ages, poor performance, abnormal hind limb gaits and shivers, in which the muscles keep twitching. PSSM is a muscle disease found in horses with Quarter Horse in their breeding, such as American Quarter Horses, Paints and Appaloosas. Symptoms include reluctance to move, muscle stiffness, sweating, shifting lameness and tremors in the flank area.
NOTE: You’ll see that these authors above recommend a starch and sugar content of 15% or less – but for “easy keepers” or those prone to laminitis or founder, many vets recommend 12% NSC or less. Also, if you are giving your horse grass turnout, then the lowest sugar levels in grass are at night, after the sun has set. The highest levels are in the morning, before the dew burns off.
Here’s a great guide to hay cutting and baling factors that affect NSC levels, from Galusha Farms:
Environmental conditions at harvest time:
1. Grasses stressed from drought conditions or freezing temperatures will contain higher percentages of NSC/NFC.
2. Stressed-out warm season grasses – such as crabgrass or coastal Bermuda grass – tend to be lower in NSC/NFC.
3. Stressed-out cool season grasses – such as fescue, orchard grass, and timothy, tend to be higher in NSC/NFC.
Maturity of plant:
1. Young plants are higher in sugar.
2. Mid-bloom and mature grass is lower in sugar.
3. Very mature plants tend to contain large amounts of indigestible fiber and can be unpalatable. The timing of harvest and curing conditions, grasses harvested in the morning, following evenings when temperatures are 40°F or above will be lower in NSC/NFC.
4. The longer hay is dried in the field, the lower the NSC/NFC. Western hays tend to be harvested later in the day and baled more quickly than Eastern hays, so they can be higher in NSC/NFC.
5. Hay that has been lightly rained on will be lower in NSC/NFC; however, it must be completely dry when baled or it will become moldy or dusty.
Laminitis or restricted feeding?
If you’re having issues with your horse’s health, or you’ve noticed that although your horse is being fed the required amount of hay for their body weight, but they are still “psychologically starving,” then this is the best book I’ve read on this topic by Dr. Juliet M Getty, PhD. She also has separate books for specific conditions like Laminitis, or the Aging Horse.
I have a number of articles and tap-along healing sessions for horses with laminitis or Cushing’s, so take a scroll through here and see what looks helpful to you.
Article updated July 2024
Jini Patel Thompson is a natural health writer and Lazer Tapping instructor. She began riding at age 2 in Kenya, and got her first horse at age 8 in Alberta, and so continues a life-long journey and love affair with these amazing creatures.
I always had horses growing up, and I finally convinced my husband to let us get a few horses now that we live in a home with a good sized area to keep them. It’s been a long time since I took care of horses, and I imagine that opinions have probably changed a lot in regard to what we should be feeding the horses, so I appreciate this information. I like how you point out that the kind of hay you choose shouldn’t be decided so much by the sugar levels, but more by what type of plant it is, whether it has bloomed/seeded or not, and the time of day the hay is cut. I’ll start paying better attention to all of those things!
Hi Jen – Congrats on your return to wonderfulness of horses! Just to clarify, as perhaps my post was confusing, hay should be chosen based on sugar levels (low sugar). But the sugar level is not just determined by the type of hay it is, but also by other factors; such as time of cutting, drought conditions (increase sugar in plants), etc. That’s why it’s best to buy from a vendor that tests their hay.
It’s good to know that you want to feed them low sugar hay if they are doing a lot of exercise. My dad was telling me last night about how he recently got some horses for his farm, and that he wants to make sure that he gets the right hay to feed them. I’ll make sure to pass this information along to him so that he can know how to choose the right kind for his horses!
Thanks for stopping by – your website has some great info, so I added it to the post along with a link to your site. Wish you guys lived near me!