Protein in Horse Feed: Protein Requirements Horses Need and Why Protein Quality Matters

When you read the feed label and it says 10 or 12 % protein, this is just a measure of the amount of protein present. The information is a little misleading. The amount is calculated from measuring the amount of nitrogen present in a sample, and taking that 16% of protein is
nitrogen, and doing a back calculation. This tends to overestimate the amount of actual protein present since there is some nitrogen in the feed that is not in a protein. It also tells you nothing about the quality of the proteins in the feed.
How Much Protein Do Horses Need?
Protein is a vital nutrient in a horse's diet, but the quantity needed varies depending on the horse's age, workload, and physiological condition. When considering protein requirements, it's important to focus not just on the total amount of protein but also on the quality of that protein. High-quality proteins provide essential amino acids, the building blocks of proteins, in the correct proportions that horses need for optimal health.
Crude protein is a term often used in horse feeds, which refers to the total protein content without regard to the protein's quality or digestibility. While the crude protein level gives an indication of the total protein present in the feed, it's the amino acid profile that determines the protein's quality. Lysine, methionine, and threonine are the limiting amino acids in equine diets, meaning they are the most likely to be deficient and thus limit protein synthesis.
Adult, idle horses typically need about 8-10% of their diet as crude protein, while growing foals and lactating mares require higher amounts, around 16-18%. This protein requirement increases with workload, as horses use protein for energy during exercise. It's crucial for horse owners to remember that too much protein can lead to health issues such as kidney damage and excessive thirst. Therefore, it's essential to balance the protein ration to match the horse's needs without exceeding them.
Common Sources of Protein in Horse Feed
Forages, including grass and legume pastures, are the primary source of protein for most horses. Legumes like alfalfa and clover usually have higher protein content than grasses. For example, alfalfa typically contains 15-20% crude protein, making it a high-quality source of protein.
Supplemental feeds like soybean meal also provide a high protein content with a good balance of essential amino acids, making it a common choice for horse feeds. Soybean meal usually has a crude protein level of 44-48%, with a high lysine content, an essential amino acid that serves as a building block for protein.
Horse feeds also commonly include grains and processed feeds, though these tend to be lower in protein and higher in starch. When considering the protein quality in these feeds, it's essential to look at the amino acid profile. High-quality proteins will provide all the necessary essential amino acids in the correct proportions.
In conclusion, understanding the protein quality and the sources of protein in horse feeds is important for meeting the protein requirements of horses and ensuring their optimal health. For horse owners, a balanced diet that provides adequate amounts of high-quality protein is essential. With the right nutrient balance, you can ensure that your horse is getting the protein it needs.
What are Amino Acids?
Amino-acids are complex molecules that are the primary components of protein chains. There are 22 amino acids that compose all the proteins the body makes and uses. 12 of these can by synthesized in the liver, the other 10 must be supplied in the diet, these are the 10 essential amino acids. The non-essential amino acids are Alanine, Asparagine, Aspartate, Glutamate, Glutamine, Glycine, Hydroxyproline, Hydroxylysine, Proline, Serine, Tyrosine. Cysteine can be regarded as a non-essential amino acid since it can be synthesized from Methionine, but only if sufficient
methionine is supplied. The essential amino acids are Arginine, Histidine, Isoleucine, Leucine, Lysine, Methionine, Phenylalanine, Threonine, Tryptophan, and Valine. These amino acids must be present in the feed and be picked from the GI tract.
Read more on our blog!
#equinenutrition #horsenutrition #horses