Amino Acids 101

Learn about the 21 amino acids that form proteins in your horse’s body and why they’re crucial to his health.

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Amino Acids 101
There are 21 different amino acids that form proteins in the horse’s body, and horses must acquire nine of those from his diet. | Photo: iStock

Have you ever read your horse’s feed or supplement label’s list of ingredients and run across an unfamiliar ingredient? Some of those unfamiliar ingredients might be amino acids, an important part of your horse’s diet. Common amino acids added to equine feeds and supplements include lysine, threonine, methionine, tryptophan, and leucine.

Here’s what you need to know about these important compounds.

What are amino acids?

The term “amino acids” refers to a group of organic compounds that contain nitrogen, carbon, oxygen, and hydrogen. Protein is made up of amino acids strung together. Horses digest proteins and then use the amino acids to help grow and repair bodily tissues. There are 21 different amino acids that form proteins in the horse’s body, and horses must acquire nine of those from his diet. These nine amino acids are known as the indispensable or essential amino acids. The horse can synthesize the remaining amino acids from other dietary components containing carbon and nitrogen

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Written by:

Sara L. Mastellar, PhD, is an assistant professor at The Ohio State University. She is originally from New York state, where she grew up keeping horses on her parents’ dairy farm and participating in Pony Club and 4-H. She earned a BPS in management specializing in Equine Business Management from Cazenovia College, where she also rode on the Intercollegiate Dressage Association team. She then earned her PhD in equine nutrition at the University of Kentucky. When not teaching or in the saddle, she enjoys spending time with her husband, two dogs, and cat.

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