Reasons to Test Your Horse’s Hay

Updated: Feb 15, 2020

While grocery shopping, do you ever look at the ingredients on the back of a product? It is likely that if you frequent my blog posts, you probably do, and it seems many people are becoming more aware of what they are putting into their bodies. (Thank heavens!) But why are we not doing the same for our horses? -- Science is beginning to understand the importance of nutrition and its roll in our horses’ long-term health, healing, and stamina. Which is why I encourage all horse owners to educate themselves too. Virtually every ailment and injury can be linked to micronutrient deficiency. To be clear this is not a fad or spoiling our hooved friends, it is imperative to our horses’ health that we know what nutrients they are or are not getting through their diet.


So here you go, reasons to test your horse hay:


To know how much hay to feed. You calculate this by using the Digestible Energy (DE) amount listed on your analysis. You can figure the average horse’s DE needs by multiplying 0.0333 x body weight in kg (to get your horse’s weight in kg, divide his weight in pounds by 2.2) Then to know the amount of hay to feed, divide the horse’s DE needs by the DE amount listed on your hay analysis. For clarity, if a horse needs 16.1 Mcal/day and the hay’s DE amount is 1.65 Mcal/kg, 16.1/ 1.65= 9.8 kg or 21.6 lbs (again, multiply by 2.2 to convert to pounds). This is how much hay you should feed per day in pounds. Of course this is merely a guideline and depending on the bio-individuality of each horse, the quality of and access time to their pasture, they may need more or sometimes less.


Because knowing the sugar/starch level is very important not only for overweight horses or horses with metabolic conditions, but all horses regardless of health. It is best to have the ESC (simple sugars most commonly referred to as 'NSC') + starch level less than 12% for overweight horses or horses with Insulin Resistance, Cushings, or other metabolic conditions. Though I recommend 12% or less to all my clients to reduce overall inflammation within the body. If your ESC + starch is slightly higher than 12%, you can reduce the sugar/starch levels by soaking it in water. The downside to soaking is that the other nutrients are then leached out into the water with the excess starch, so it is important to source hay that is 12% or lower from the start.


Vitamins and minerals are in hay too, but are they enough? When you get your hay tested, you will no longer be guessing which minerals you need, or do not need, to supplement. Combining hay testing with hair mineral analysis will stop the guessing when it comes to what nutrients your horse has enough of in its body, is getting through its feed, and what still needs to be supplemented. (If you are interested in hair mineral analysis contact me for pricing and sample submission information.)


Your horse could be iron overloaded. It is fairly common that hay (and pasture grass) is high in iron. There may not be a whole lot you can do about the iron, but you can counteract the abundance of iron by supplementing more zinc and copper, possibly manganese, and bring the trace minerals into balance as well. What is important to understand is that micronutrients (vitamins and minerals) work together in teams called co-factors. When one or more of these co-factors is out of balance (determined by ratios) then depletion of the others occurs leading to deficiencies. Deficiencies then lead to a myriad of health issues


How to Take a Hay Sample:

The next thing people usually want to know is HOW do you go about getting your hay tested? Thanks to companies like Equi-Analytical, it is far easier than you might think. Here is what you will need:


- Hay probe (you can might be able borrow one from your local university extension office or you can buy one. If you purchase one through Equi-Analytical, you can get a free hay analysis as part of the probe price.)

- Electric Drill

- Large plastic baggie


Now for the action:

- Fasten the hay probe to the drill.

- Probe the center of about 15 randomly selected bales from one hay batch.

- Separate probe from drill after sampling each bale and push the hay out with a plunger or stick and into the baggie.

- Send baggie in for analysis.


Viola! Simple as that.


As always, if you have questions or concerns, I'm here to help!

Photo from our good friends at Naturally Healthy Horse
Probe the center of about 15 randomly selected bales from one hay batch.