Methionine is an essential amino acid that is important for maintaining healthy hooves, tendons and ligaments, and supporting coat quality. Growing horses and heavily exercised horses have a high demand for methionine and benefit from supplementation.
DL-Methionine is an essential sulfur-containing amino acid that serves as a building block for proteins involved in metabolism, growth, and tissue repair. Because horses cannot synthesize methionine internally, it must be obtained from feed or supplementation. It is often identified as the second-most limiting amino acid in equine diets, meaning insufficient methionine can restrict overall protein synthesis even when other amino acids are present in adequate amounts.
Methionine supports the formation of structural proteins such as keratin and collagen, contributing to strong hooves, healthy skin, and a glossy coat. It also plays a critical role in maintaining connective tissue integrity, supporting joints, ligaments, and tendons. In the nervous system, methionine assists in the production of neurotransmitters such as serotonin and helps support normal mood and focus.
Biochemically, methionine acts as a precursor for several important compounds, including taurine, L-carnitine, and cysteine. It is also required for the synthesis of S-adenosylmethionine (SAMe), a key methyl donor involved in cellular metabolism, detoxification, and liver health. Through its conversion to cysteine and subsequently glutathione, methionine supports antioxidant defense and helps protect tissues from oxidative stress.
According to the NRC’s Nutrient Requirements of Horses, a 500 kg (1,100 lb) horse at maintenance requires approximately 7,500 mg of methionine per day. Supplementation may be beneficial for horses on high-fiber or low-protein diets, those in heavy training, or horses needing nutritional support for hoof growth and coat quality.
Please consult a qualified nutritionist or veterinarian for recommended inclusion rates in your horse’s diet.
Top dress once daily on feed or ration.
| Body Weight | Scoops | Dose |
| < 200 kg | ½ scoop | 2.5 g |
| 200 – 500 kg | 1 scoop | 5 g |
| > 500 kg | 1 ½ scoops | 7.5 g |
| 1 scoop = 9 cc = 5 grams | ||
A scale should be used with all individual ingredients to ensure accurate dosing.
For Equine Use Only. Not for use in horses intended for food. Keep out of reach of children.
| Active Ingredients: Per gram serving |
|||
|---|---|---|---|
| Ingredient | Per 5 g | ||
| DL-Methionine | 5 | g | |
Recommended Use: Supports hoof, tendon, ligament, and coat health.
Packaged by: Mad Barn Inc., Petersburg, ON, N0B 2H0, Canada.
1 kg (2.2 lb): SKU 628055182177
| kg | ||
| grams | ||
| Servings | Cost Per Day |
|---|
Have a question about this product? Ask below and our nutritionists will be happy to assist.
Essential Sulfur-Containing Amino Acid
Mad Barn's Methionine is a 99% pure crystalline DL-methionine powder used to correct inadequate methionine intake and improve the balance of essential amino acids in the diet.
Methionine is required to produce proteins in hoof horn, skin, muscle, cartilage and connective tissues. It also supplies sulfur for the production of cysteine and glutathione, an important cellular antioxidant.
Why Horses Need Methionine
If your horse has brittle hooves that crack, chip, or crumble, their diet may be lacking essential amino acids. Healthy hoof growth depends on adequate intake of sulfur-containing amino acids such as methionine, which is used to produce keratin, the structural protein that gives hooves their strength.
Horses cannot make methionine on their own, so it must come from forage, feed or supplements. Commonly fed cereal grains and grasses are typically low in methionine, along with lysine and threonine.
As a result, methionine is often considered the second limiting amino acid in equine diets. When methionine intake is inadequate, the body cannot use all other available amino acids efficiently to produce new proteins, even if total crude protein intake meets requirements.
Supplementing DL-methionine can correct amino acid imbalances, allowing your horse to make better use of the protein in their forage and feed. Adequate methionine supports hoof growth, coat quality, muscle maintenance, tissue repair and normal exercise recovery by providing the building blocks required to make these proteins.
99%
Pure DL-Methionine
Single-ingredient crystalline powder without added sugars, starches, sweeteners or fillers.
Essential
Amino Acid
Must be supplied in the equine diet and is required for normal protein synthesis.
5 g
Standard Serving
One easy-to-feed scoop per day for horses weighing 200 – 500 kg (440 – 1,100 lb).
$0.17
Cost Per Day
Affordable pure amino acid supplement, with a 1 kg (2.2 lb) container lasting 200 days for typical horses.
Horses with slow hoof growth, cracked or crumbling hooves, or poor coat quality benefit from methionine supplementation when dietary intake is inadequate. Horses fed mature grass hay or grain-based diets with low protein quality are also at risk of methionine deficiency, even when total crude protein levels are sufficient.
Growing horses, lactating mares, and horses in exercise training have higher protein and amino acid requirements to support physiological needs. In addition to poor hoof and coat condition, signs of inadequate essential amino acid intake can also include muscle loss, reduced stamina, and low milk production in lactating mares.
Methionine supplies sulfur needed to produce cysteine, an amino acid involved in the structure of keratin in hooves.
A dull, rough coat or poor hair growth can accompany inadequate protein quality. Methionine is required to produce proteins in hair and skin.
Horses fed primarily mature grass hay or underfortified cereal grains may get enough crude protein but still lack essential amino acids such as methionine.
Even with adequate calorie intake and exercise, insufficient limiting amino acids can impair muscle protein synthesis and topline maintenance.
Regular or intense training increases protein turnover and demand for amino acids used in muscle development and recovery.
Foals and young horses require higher concentrations of essential amino acids for the rapid formation of muscle, cartilage, and bone-associated tissues.
Pregnancy and lactation increase protein and amino acid demands for fetal development, maternal tissues and milk protein production.
Aging horses losing muscle or eating less forage and feed may need dietary adjustments to maintain sufficient essential amino acid intake.
Horses recovering from illness or injury need balanced amino acids to support tissue repair and normal immune function.
Methionine Requirements
Horses cannot make methionine on their own, so they must obtain it from their diet. The National Research Council (NRC) provides scientific guidelines for how much of each nutrient horses need to maintain normal health. Based on these guidelines, a typical 500 kg (1,100 lb) adult horse at maintenance needs approximately 7.5 grams of methionine per day.
This requirement is calculated as 1.2% of dietary crude protein intake, based on a protein requirement of approximately 630 grams. These figures represent the total methionine needed from the diet, not the amount that must be supplemented. Requirements vary with body weight, age, workload, growth, pregnancy, and lactation.
7.5 g
Maintenance
Estimated methionine requirement per day for a 500 kg (1,100 lb) adult horse at maintenance.
8.4 – 10.3 g
Exercise
Estimated requirement per day for a 500 kg (1,100 lb) horse in light to heavy work.
8 – 10.2 g
Growing Horses
Estimated daily requirement for growing horses aged 4 – 24 months, with an expected mature weight of 500 kg (1,100 lb).
18 g
Lactating Mares
Estimated daily requirement for a 500 kg (1,100 lb) mare during the first three months of lactation.
How Methionine Works
Methionine is an essential sulfur-containing amino acid used by cells to build proteins and synthesize other important compounds. It is the initiating amino acid in the production of most new proteins, and adequate methionine must remain available as the protein chain is assembled.
Beyond its role in protein formation, methionine is converted through metabolic pathways into cysteine and S-adenosylmethionine (SAMe). These compounds support normal tissue structure, antioxidant defense, methylation and cellular metabolism.
Methionine is needed to initiate protein production and supply amino acids for muscle growth, tissue repair, metabolic enzymes and immune proteins.
Methionine supplies cysteine, which forms sulfur-containing bonds in keratin and supports the structural proteins of hooves, skin and connective tissue. Sulfur metabolism also contributes to cartilage compounds associated with glucosamine.
Cysteine derived from methionine is used to form glutathione, a cellular antioxidant that helps regulate oxidative stress during normal metabolism, exercise and immune activity.
Methionine is converted into SAMe, which transfers methyl groups (CH3) to DNA, proteins and other compounds. Methylation helps regulate which genes are active and supports normal liver and cellular metabolism.
Methionine for Hoof Health
The horse's hoof wall is composed mainly of keratin, a structural protein that protects the internal hoof and withstands repeated loading. Keratin contains the sulfur-bearing amino acid cysteine. Disulfide bonds between cysteine residues reinforce keratin, contributing to the strength and durability of hoof horn.
Methionine is metabolized into homocysteine, which is converted into cysteine through the transsulfuration pathway. Cysteine is then used to synthesize keratin in hooves and hair.
Methionine also contributes sulfur needed for the formation of sulfated glycosaminoglycans in cartilage and other connective tissues. These compounds contain amino sugars, including glucosamine, and help retain water within the extracellular matrix, contributing to joint structure and resistance to compression.
Horses with cracking, crumbling or slow-growing hooves> may no be getting enough methionine or other essential amino acids. Supplementing methionine alongside biotin, zinc and copper as part of a balanced diet can help support normal hoof growth and quality.
Nutritional improvements affect newly growing hoof horn rather than repairing existing hoof tissue, so supplementation should be maintained consistently for 8–12 months to support the growth of a complete new hoof wall.
Antioxidant and Immune Function
Methionine is an important precursor for glutathione, a tripeptide antioxidant present in cells throughout the body. Glutathione helps protect cells from oxidative damage and participates in normal liver metabolism and detoxification pathways.
Strenuous exercise, inflammation and illness increase oxidative stress. Horses with inadequate methionine intake could experience signs of reduced antioxidant defenses, including slow recovery from exercise and more frequent or prolonged illness. Adequate methionine helps support normal immune function and resistance to physiological stress.
Horses with frequent allergic reactions, including heaves, may also benefit from supplemental methionine to support antioxidant status. Studies have found elevated levels of oxidized glutathione in the airway lining fluid of affected horses during flare-ups, indicating increased oxidative stress in lung tissue.
Best Amino Acid Supplements
Pure Methionine is most appropriate when a diet evaluation identifies low methionine and the other essential amino acids are already adequately supplied.
For overall support of topline, muscle development, growth and performance, a blend supplying lysine, methionine and threonine together is usually better than adding individual amino acids.
Precision Formulation
Best when you specifically need to increase methionine without adding other amino acids or nutrients.
Best for Most Horses
Mad Barn's Three Amigos supplies lysine, methionine and threonine together in a 5:3:2 ratio to improve the amino acid balance of the overall diet.
Feeding Instructions
For horses weighing 200 – 500 kg (440 – 1,100 lb), add 5 grams to their regular ration.
The complete diet must provide enough total protein for your horse's age and workload.
Ensure intake of lysine, threonine, and other essential amino acids also meets your horse’s requirements.
100% Customer Happiness Guarantee
We're confident you'll love Methionine. If you're not satisfied with the product, our team is here to help you find the right solution or provide a full refund.
Less than 1% of customers ever use our satisfaction guarantee.
Expert Support
Every horse is different, including their forage, turnout, workload, body condition, age, supplement regimen, protein and amino acid intake, and health history. Always consult a qualified nutritionist or veterinarian before changing the feeding program, especially when inadequate protein or amino acid intake is suspected.
One of our equine nutritionists can provide a complimentary review and help determine whether Methionine or Three Amigos is the best fit.
All-In-One Vitamin & Mineral Pellet
Advanced Gut Health Supplement
DHA-Enriched Fat Supplement
All-In-One Vitamin & Mineral Pellet
All-In-One Vitamin & Mineral Powder
Enhanced Vitamin & Mineral Pellet
Advanced Gut Health Supplement
Probiotic & Prebiotic Supplement
High-Potency 5-Strain Probiotic
All-In-One Vitamin & Mineral Pellet
Enhanced Vitamin & Mineral Pellet
Hoof, Skin & Coat Support
Extra-Strength Omega-3 Oil
Joint Health Supplement
DHA-Enriched Fat Supplement
DHA-Enriched Fat Supplement
All-In-One Vitamin & Mineral Pellet
Organic Trace Mineral Blend
Enhanced Vitamin & Mineral Pellet
Mood & Hormone Support
Metabolic Health Formula
Mood & Hormone Support
Muscles & Nerve Support
Advanced Gut Health Supplement
Advanced Gut Health Supplement
Respiratory & Performance Supplement
Essential Amino Acid Blend
Essential Amino Acid Blend
Muscles & Nerve Support
Performance & Muscle Support
Respiratory & Performance Supplement
DHA-Enriched Fat Supplement
Immune & Respiratory Support
English
AminoTrace+ 
DL-Methionine 
Omneity® Pellets 
Omneity® Premix 
Three Amigos 
Visceral+ 
