Horse Hay and Pasture Testing for the Winter

October 24, 2018 (published)

As we enter the fall and winter, the pasture grass is declining in quality and we will be needing to feed hay to our horses.  In the past, you just called the feed store or hay supplier and told them you needed hay, but now we know that all hays are not the same.  With the discovery of Cushing’s disease or PPID and equine metabolic syndrome, we now know that many of these horses need a low-carbohydrate ration. Grass hay can have anywhere from 5 to 35 percent carbohydrates as reported by Equianalytical Lab.  Since horses with insulin resistance need to be eating hay that is less than 10 percent nonstructural carbohydrates, if you have insulin-resistant horses, it is important to know the carbohydrate values of the hay before you buy it.  Hopefully, your hay dealer tests their hay but if they do not, ask them to do so. 

If you test the hay yourself, you will need a hay probe, an electric drill, and a one-quart plastic bag to contain the sample.  You would want to sample at least 10 bales and should send at least a pound of hay to the lab.  If you also want to sample the pasture, take about 20 samples at different areas and with scissors, cut off the portion of the plant the horse is eating.  So, if the horse is not eating close to the ground, do not sample that portion.  Cut up the grass in two-inch segments and mix it thoroughly.  Testing is available for all parameters in hay and pasture if you want to do it. If you are a hay producer, this would be a good idea.  However, if you have horses that are resistant to insulin, you can just ask for a starch panel as these tests are fairly inexpensive and certainly worth the money.  Many labs can provide this information.

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