Milk Thistle

“Milk Thistle is a natural source of flavonolignans that support normal liver function and antioxidant enzyme activity. These compounds help maintain healthy detoxification and hepatic metabolism in horses under metabolic or environmental stress.”

—

Dr. Priska Darani, PhD

Equine Nutritionist, Director of Research

Milk Thistle Supports:

• Liver Function

• Metabolic Health

• Antioxidant Defenses

• Immune Function

• Detoxification Processes

• Coat Quality and Skin Health

• Resistance to Stress

• Post-Exercise Care

• Normal Blood Sugar Regulation

• Overall Well-Being

Mad Barn’s Milk Thistle is a dried, powdered form of the seed of the Silybum marianum plant. This herb can be added to equine diets to support healthy liver function and provide antioxidants.

Milk Thistle, also known as St. Mary’s Thistle, is a Mediterranean plant that contains various active compounds collectively called silymarin which include silybin. The main site of action of milk thistle is the liver and it has been well-researched for its effects on liver function in humans. [1]

Silymarin is an effective antioxidant that is thought to support the liver in times of injury related to toxins, fat accumulation, and iron overload.

Milk thistle helps protect the liver from toxins in the environment, like those found in poisonous mushrooms, ragwort or red maple trees. If these are prevalent in your area, consider adding milk thistle to your horse’s diet.

Horses and ponies with hyperlipemia may have excess fat in the liver. Milk thistle supplementation may help to support their liver and its normal function. In humans, silymarin has been shown to protect against the negative effects of fat accumulation in the liver. [2]

Milk thistle could provide nutritional support for horses with laminitis. In one study, tissue extracted from horse hooves was challenged with toxins and treated with milk thistle or silymarin. The protocol was able to neutralize the toxin and improve the structural integrity of the tissue. [3] Further research is needed to verify these effects in horses consuming oral milk thistle supplements.

Silymarin also acts as an iron chelator, meaning it binds iron molecules and may help reduce serum ferritin levels and iron stores in tissues. [4] In humans that are genetically prone to iron overload, this herb has been shown to decrease iron absorption.

To include Mad Barn’s milk thistle in your horse’s diet, we suggest a dosage of 4 grams per 500 kg (1100 lb) of bodyweight per day. You may want to start feeding a smaller amount and increase gradually over several weeks to minimize avoidance. It can be provided as dried powder added directly to the feed.

Milk Thistle is generally well tolerated in horses. It has not been studied in breeding or pregnant horses so its safety in these animals can not be assured.

In healthy horses, concentrated milk thistle extract in the form of silibinin phospholipid did not cause adverse effects when given at a dose of up to 52 mg per kg of bodyweight (26 grams for a 500 kg horse) for one week on four separate occasions. [5]

References

• Mulrow, C., et al. Milk Thistle: Effects on Liver Disease and Cirrhosis and Clinical Adverse Effects: Summary . AHRQ Evidence Report Summaries. 2000.

• Cacciapuoti, Fulvio et al. Silymarin in non alcoholic fatty liver disease . World J Hepatol. 2013.

• Reisinger, Nicole et al. Milk Thistle Extract and Silymarin Inhibit Lipopolysaccharide Induced Lamellar Separation of Hoof Explants in Vitro. Toxins. 2014.

• Hutchinson, Carol et al. The iron-chelating potential of silybin in patients with hereditary haemochromatosis. Eur J Clin Nutr. 2012.

• Hackett, Eileen S. et al. Pharmacokinetics and safety of silibinin in horses . Am J Vet Res. 2013.