All Life Stages • All Performance Levels • All Forage Diets

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About Equine Challenge Horse Supplements | Equine Nutrition

Equine Challenge was created by Dr. Mackie K. Hartwig, a highly accomplished Equine Nutritional Speaker and OMT Practitioner.  After 19 years in practice Dr. Mackie Hartwig retired in 2005 to dedicate his life to bettering the lives of horses. Mackie taught equine stewardship classes to horse care professionals and horse owners throughout the country, focusing on equine nutrition, spinal, dental and hoof care.

With his extensive background in science, Mackie had years of experience in nutrition, focusing on the synergy of ingredients to achieve optimal results. When he and his wife Kathy started their Morgan farm in 2005, Mackie discovered a lack of available quality nutritional options, and he went to work in creating Equine Challenge Supplements. 

Dr. Mackie Hartwig of Equine Challenge Supplements for horses

From its inception Equine Challenge Supplements quickly became a popular line of specially formulated forage specific nutritional supplements for horses, sold throughout the United States.  Before starting his career as a doctor Mackie served 4 years in the U.S. Military as an Airborne Army Ranger. Mackie made his home with his wife Kathy and their Morgan horses, in Clovis, California where they provided nutritional counseling, equine nutritional supplements, equine rehab, barefoot hoof trimming, and horse training, until the time of his passing in 2013.

Mackie’s wife Kathy continues to carry on their dream, dedication and commitment to providing a complete line of the highest quality nutritional forage specific horse supplements to owners and trainers across the United States.

Mackie & Kathy Hartwig

All Life Stages/All Performance Levels/All Forage Diets

At Equine Challenge™ Supplements we believe in pro-active nutrition for your horses. That means building your horse’s immune system and becoming metabolically sound. From supporting sick, injured, rescued horses to maintaining wellness to supporting your equine athlete.  We will provide the highest quality horse supplements so that your horse not just lives, but actually thrives.  We believe forage specificity is paramount before horses get sick, not after! Sadly, more times than not we consider diet specificity when our horses become sick and we want them to recover functionally and quickly.

Equine Challenge™ is pro-active nutrition which provides the basic building blocks for day to day life and allows the flexibility to meet the nutritional needs of horses, regardless of how little or how much is physically demanded.

Not only are our ingredients synergistically proportioned in the bag, they are synergistically balanced to compliment whatever forage you feed your horse, be it alfalfa, grass or oat hay.  Our horse supplements can be mixed with your horse’s grain, hay pellets or simply fed by itself right out of the bucket. Equine Challenge Supplements will get your horse metabolically sound while supporting the immune system, digestive system, optimal hoof growth and healthy skin and coats.

Equine Challenge™ is a milled food grade Flaxseed based forage specific horse supplement, highly bio-available daily vitamin, mineral trace element and digestive probiotic supplement.  Equine Challenge™ offers a complete line of supplements for horses to support hoof, joint, tendon, ligament, digestion, topline improvement, muscle mass improvement, fly control, calming/blood builders and herbal support, essential oils and more.  Please visit our complete line of products by visiting our horse supplements shopping page.

During milling we use a high speed micronizing technique which slices the flaxseed instead of crushing, avoiding rupturing the fat cells at a lower temperature. This yields a very stable product that has a shelf life of 6 months or more with reasonable storage.

Hello Kathy, I hope you are doing well. I have been a very satisfied Equine Challenge customer for years. So much that most of my client's and training horses are on it as well. This is a picture of my Belgian Warmblood, Nextravagant, at his 2 year old Keuring. He grew up from conception on Equine Challenge. Thank you for providing such an outstanding product!
Rebekah Larimer Testimonial
Rebekah Larimar
Rebekah Larimar Training

Benefits Of Equine Challenge Supplements

  • High palatability
  • High Bioavailability (Chelated)
  • Easy to administer
  • Food grade Flax rich in Omega 3’s
  • 7 Strain viable Probiotic package
  • ZinPro Amino Acid Complexes
  • No byproduct fillers
  • No Added Iron
  • No Soy
  • Guaranteed freshness
  • Cost effective
  • Easy to feed
  • Easy to use, easy to open bags, pails and drums
  • Equine Challenge Supplement™ products made to work synergistically together
  • Products developed along with a manufacturer with over 40 years Nutritional experience & history
  • Shipping is always included in our pricing, anywhere in the 48 contiguous states + Alaska & Hawaii (call for shipping costs to Canada).


Equine Challenge Supplements™ contain no byproducts or fillers such as Distiller’s Dried Grain solutes, ground alfalfa, wheat millrun, wheat middlings, soymeal, beet pulp, rice bran, soybean or oat hulls. Equine Challenge Supplement™ products contain no corn, no wheat, no alfalfa, no soy beans, no molasses, no soy oil, no mineral oil, no vegetable oil and no corn oil. The oil in Equine Challenge Supplements™ is the oil naturally found in Flaxseed, primarily Omega 3’s and Omega 6’s.

Equine Challenge Supplements™ are synergistically proportioned to provide the nutritional building blocks and maintain the metabolic balance of your horse, regardless of whether you feed alfalfa, grass or oat hay.

Thank you for taking The Equine Challenge and choosing Equine Challenge Supplements!