Amino Acids: The Building Blocks of Equine Nutrition
- Jul 18
- 3 min read
Amino acids are the building blocks of proteins, which are essential for muscle development, tissue repair, enzyme production, and overall equine health.
Horses require specific amino acids in their diet because they cannot synthesise all of them internally.
You don't need to buy an expensive "amino acid" supplement. You can supply their protein requirements in feeds.
Essential and Non Essential Amino Acids
Essential amino acids such as lysine, methionine, and threonine must be supplied through the diet.
Lysine, one of the most critical amino acids, supports muscle development, especially in young and performance horses.
Methionine plays a role in keratin production, crucial for strong hooves and a shiny coat.
Threonine plays a vital role in various physiological processes, particularly in muscle maintenance, immune function, and gut health.
Non-essential amino acids can be synthesised by the horse’s body. They do this in the liver by recycling other amino acids. The horse can transfer an amine group from another amino acid to a keto acid, creating a new amino acid. Example: Glutamate donates its amine group to pyruvate, forming alanine. Alanine is important for supplying energy to the exercising muscle,
If your horse is getting enough protein in their diet, they should not be deficient in these amino acids.
Key Non-Essential Amino Acids in Horses
Glutamine – Supports gut health, immunity, and muscle recovery.
Glycine – A component of collagen, aiding in connective tissue and joint health.
Serine – Helps with enzyme production and cellular function.
Proline – Vital for collagen formation, skin, and hoof structure.
Alanine – Involved in energy metabolism and glucose regulation.
Aspartic Acid – Supports neurotransmitter function and cellular energy.
Glutamic Acid – A precursor for neurotransmitters and brain function.
Arginine – Plays a role in circulation, immune defense, and cell growth.
Cysteine – Contributes to antioxidant defense and keratin production for hooves and coat.
Tyrosine – A precursor for neurotransmitters like dopamine and adrenaline.
Amino Acid Deficiency
If a horse lacks essential amino acids, it can lead to poor muscle development (top line), slow recovery from exercise, dull coat, weak hooves, and overall decreased performance.
To be fair, these are also symptoms of deficiencies in minerals generally - parasite burden, or even just salt deficiency.
Ideally, you are going to meet all their needs in the diet, including amino acids.
Horses obtain essential amino acids through protein-rich feed sources. Since they cannot synthesise these amino acids internally, their diet must supply them adequately.
Here are some key dietary sources:
High-Quality Protein Sources
Lucerne (Alfalfa) Hay – Rich in lysine, one of the most crucial amino acids for muscle development. Lucerne has been a staple feed for horses for centuries. Even Aristotle mentions alfalfa as a superior feed for horses.
Soybean Meal – One of the best plant-based protein sources, high in lysine and methionine.
Peas and Lupins – Great sources of protein with good levels of lysine and leucine.
Flaxseed (Linseed) – Provides protein and supports coat and hoof health, though it is not as high in lysine as soy. Flax also has many other benefits for your horse. We sell flax/linseed as whole seeds, or as a meal (ground).
Yeasts – Contains B vitamins and amino acids that aid digestion and overall metabolism.
Spirulina - Considered an equine “superfood” because it contains all the essential amino acids, as well as vitamins and minerals that provide antioxidant and anti-inflammatory benefits. Further, studies (in humans) show spirulina is a natural anti-histamine for conditions such as hay fever. We have many clients using spirulina for chronic respiratory or skin conditions, and for idiopathic headshaking.
To meet amino acid requirements, we feed our own horses straight lucerne hay, full fat soy bean meal, flaxseed and Yea Sacc, which is a specific strand of saccharomyces cerevisiae formulated for supporting gut health in livestock.
With optimal nutrition, many chronic conditions that result from nutritional deficiencies simply never arise.
Here are links to further reading on amino acids:
Comments