Winter Hay and Pasture Testing for Horses

December 11, 2018 (published)

In fall and winter, the pasture grass declines in quality and we need to begin feeding 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, and it has been shown that grass hay can have anywhere from 5-35 percent carbohydrates as reported by Equianalytical Lab.  If you have a horse with insulin resistance, who need to be eating hay that is less than 10 percent nonstructural carbohydrates, 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 want to sample the pasture also, take about 20 samples at different areas by using scissors to cut off the portion of the plant the horse is eating.  If the horse is not having to eat close to the ground, you don’t need to sample that portion.  Cut up the grass in 2-inch segments and mix it thoroughly.  Testing is available for all parameters in hay and pasture if you want to do so; 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 and these tests are fairly inexpensive and certainly worth the money. 

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