Methionine is one of the essential amino acids and a major limiting amino acid in the diets of horses.
This amino acid is a methyl donor which means it has the capacity to alter the structure of other molecules. The methyl molecule is essential for the formation of nucleic acid (RNA/DNA) which is the genetic material of every cell in the body. This determines the blueprint of all the different proteins in the body.
Methionine is the precursor to the amino acids cysteine and cystine which along with methionine are involved in synthesising a number of very important compounds such as coenzyme A (essential for fatty acid synthesis), heparin, lipoid acid and glutathione.
Methionine is a sulphur bearing amino acid and is an antioxidant, critical for delivering lecithin and transports selenium.
Forage is the highest methionine containing feed for horses, but the soil upon which the forage is grown must be properly fertilised to balance the sulphur levels. When sulphur levels in the soil are low then methionine is impacted and this very important essential amino acid can be at very low levels in horse diets. As there is no known recommended methionine level for horses if it is suspected that the nitrogen sulphur ratio of the forage is above 10:1 then supplementation of methionine is very wise insurance.
Often if methionine is supplemented an improvement in hoof health, skin health and hair health is seen along with an improved immune system and better carbohydrate metabolism.
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