Optimum Probiotic

Optimum Probiotic

Starting at $19.99

4.8857142857143 out of 5 based on 35 customer ratings
(35 customer reviews)

Mad Barn’s 5 strain blend of probiotic bacteria is formulated specifically to help balance the horse’s gut microflora, support digestive function and the immune system. No fillers, simply a great probiotic supplement at the lowest possible cost.  2 months for $20!!! WOW

Horse Supplements Canada Canadian customers, please visit Mad Barn Canada to place your order.
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We stand behind our products to provide the best nutrition for your horse. No fillers, just research-backed ingredients. If your horse doesn't love this product, our Customer Happiness team is here to help or give you a refund guaranteed.
Optimum Probiotic Supports:
  • Gut Health
  • Improved Digestion
  • Proper Intestinal pH
  • Immunity
  • Protection from Toxins
  • Nutrient Absorption
  • Feed Efficiency
  • Weight Gain
  • Prevention of Colic & Diarrhea
  • Allergies & Skin Conditions

Mad Barn’s Optimum Probiotic is a blend of 5 pure bacterial strains shown to promote healthy intestinal flora, digestive comfort, and immunity in the horse.

Our once-daily equine probiotic supplement has been scientifically formulated for regular maintenance of gut health and for preventing digestive issues.

Optimum Probiotic is a highly concentrated formula consisting of 5 probiotic strains that are resistant to stomach acid, bile and digestive enzymes, working to populate your horse’s gastrointestinal tract with beneficial microorganisms.

Each serving of Optimum Probiotic provides a guaranteed minimum of 20 billion viable CFUs (Colony Forming Units) of Lactobacillus acidophilus, Lactobacillus fermentum, Lactobacillus casei, Lactobacillus plantarum, and Enterococcus faecium.

Looking for even more powerful protection for your horse’s digestive system? Consider our Optimum Digestive Health supplement which contains probiotics along with prebiotics, digestive enzymes, yeast cultures and more.


Why Use Optimum Probiotic?

Probiotic bacteria exist naturally throughout your horse’s gastrointestinal tract, playing an important role in metabolism, nutrient absorption, vitamin & protein synthesis, feed efficiency and overall digestion. These beneficial microorganisms also help to maintain appropriate pH balance by producing lactic acid, inhibiting the growth of pathogens and supporting the immune system.

However, the delicate balance between good bacteria and bad bacteria is frequently upset by changes in diet, excess grain consumption, stress, environmental factors, illness, medication use and more. If your horse’s gut microbiota becomes imbalanced, dysbiosis can occur leading to potential symptoms including:

  • Diarrhea or loose stools
  • Abdominal pain, bloating or constipation
  • Colitis, laminitis or colic
  • Impaired immune function
  • Gastric Ulcer Disease
  • Weight loss or ill thrift
  • Systemic inflammation
  • Poor skin & coat quality
  • And more…

Regular use of direct-fed microbials like our Optimum Probiotic supplement can prevent dysbiosis by seeding the horse’s gut with large quantities of beneficial bacteria, maintaining a favourable microflora population.

But not all probiotics work equally well. Many products on the market simply do not supply enough bacterial colonies to be effective, providing a fraction of the dosage required to make a meaningful impact. Other products are composed largely of fillers or contain probiotic cultures that die off before they reach their intended site of action in the gut. And COST a lot more!

That’s why we designed Optimum Probiotic to be a pure, cost-effective equine probiotic that replenishes gut bacteria with strains proven to work and deliver real benefits to your horse. No marketing hype. Simply a great probiotic supplement at the lowest possible cost.

Instead of paying for fillers, unnecessary ingredients or supplements with ineffective dosages, choose Mad Barn’s Optimum Probiotic:

  • Guaranteed 20 billion CFUs per serving
  • Pure 5-strain blend with no fillers
  • The best value for your money

Does My Horse Need Probiotics?

If you answer yes to any of these questions, your horse may benefit from the inclusion of bacterial probiotics like Mad Barn’s Optimum Probiotic.

  • Has your horse recently received NSAID’s like Banamine, Bute or Firocoxib?
  • Is your horse currently taking antibiotics and/or wormers?
  • Does your horse show signs of digestive upsets, have loose stools or bouts of equine diarrhea?
  • Does your horse appear underweight or unthrift?
  • Is your horse elderly?
  • Has your horse recently experienced an illness, infection or other stressor?
  • Have you recently changed your horse’s diet or environment?

Supplementing beneficial bacterial probiotics can help to restore your horse to optimal health and well-being faster. Get your horse’s microbiome back on track with Optimum Probiotic.


Ease of Use

Adding probiotics to your horse’s diet is now more economical than ever with Optimum Probiotic powder for horses, costing as little as $0.25 per day.

Optimum Probiotic is highly concentrated. Simply feed a single 1-gram scoop per day to supply the recommended serving size of 20 billion CFUs.

This extremely low inclusion rate along with high palatability means there will be no issues with fussy eaters leaving the supplement behind!


The Right Combination

Optimum Probiotic is composed of a hardy blend of 5 natural bacterial strains that grow at a wide range of pH conditions.

Probiotics only work if they are alive when they reach the gastrointestinal tract. The digestive system can be a hostile environment for bacteria to traverse, between the acidic conditions of the stomach, enzyme activity and bile in the small intestine and the competitive environment of the hindgut.

Containing 5 strains that are able to flourish in all environments, Optimum Probiotic ensures maximal activity in all areas of the digestive tract.

These lactic-acid producing bacteria competitively inhibit the growth of disease-causing pathogenic bacteria and help to clear out toxins from the digestive system. They also contribute to improved fiber breakdown and nutrient assimilation from feeds, supporting energy metabolism and healthy weight gain.

Research continues to uncover benefits linked to probiotic supplementation in horses and other animals. Optimize your horse’s gut today with Optimum Probiotic.

You should always consult a qualified nutritionist before altering your feed program. Submit your horse’s diet for analysis online and one of our equine nutritionists will be happy to provide a complementary review.

Enterococcus Faecium2019-09-09T15:43:58-05:00

Enterococcus FaeciumEnterococcus Faecium is one of the most prevalent species of probiotic bacteria found in the gastrointestinal tract of the horse. E. Faecium is a Gram-positive bacterium, has low pathogenicity and is found most abundantly within the large colon.

Probiotics are beneficial bacterial that contribute to the health of the horse by aiding digestive function and nutrient utilization, combating the growth of harmful bacteria and supporting immune function. In research studies involving animals, this bacterial has been shown to inhibit the growth of pathogenic E. coli bacteria while enhancing the growth of certain probiotic strains of Lactobacillus.

Supplementing with probiotics like E. Faecium may be particularly beneficial to horses with digestive upsets or following a course of antibiotic treatment. Adding direct-fed microbials to your horse’s diet can help to restore balance in the intestinal micro-flora and alleviate digestive complaints. Enterococcus Faecium is commonly recommended to horses experiencing diarrhea.

Lactobacillus Acidophilus2019-09-11T12:18:20-05:00

Lactobacillus AcidophilusLactobacillus Acidophilus is one of the most widely supplemented species of Lactic Acid Bacteria with well-researched probiotic effects. These bacteria produce lactic acid in the gastrointestinal tract by breaking down carbohydrates (sugars) like lactose. L. Acidophilus helps to maintain an acidic environment in the gut that is not hospitable to pathogenic bacteria and germs.

L. Acidophilus exists naturally within the horse’s microbiota, but adding this probiotic to the diet in adequate quantities can help to improve the balance between good and bad bacteria within the intestines. These bacteria attach to the gut wall, limiting the number of places where harmful bacteria can gain a foothold and begin to colonize. This may improve digestion processes and contribute to overall health by supporting the immune system.

In horses, Lactobacillus Acidophilus supplements are believed to enhance nutrient uptake from food, assist in hind gut fermentation and help maintain a healthy pH balance.
L. Acidophilus may also reduce digestive issues such as colic and scours.

Lactobacillus Casei2019-09-12T14:39:28-05:00

Lactobacillus CaseiLactobacillus Casei is a species of Lactic Acid Bacteria from the Lactobacillus genus that is noted to have probiotic effects in a wide range of acidity and temperature conditions. It is commonly supplemented together with L. acidophilus because the two species support each others growth.

Within the gastrointestinal tract of the horse, balancing the microflora can promote improved nutrient utilization, digestion, and build immunity. L. Casei has been studied for its effects on colic, diarrhea, ulcerative colitis and other gastrointestinal issues.

In research studies, supplementation with L. Casei has been shown to reduce the probability of intestinal infections and improve bowel regularity. This beneficial bacteria helps to protect the horse from pathogens by competing with harmful bacteria for resources and space on the intestinal walls. L. casei also produces bacteriocins or antimicrobial proteins and stimulates lymph tissue to release substances that combat infections.

Lactobacillus Fermentum2019-09-12T14:01:44-05:00

Lactobacillus FermentumLactobacillus Fermentum is a Gram-positive species of Lactic Acid Bacteria that exists naturally in the horse’s gut bacteria population. Like other probiotics, it helps to support healthy digestive function, immune response and increased nutrient absorption.

L. Fermentum helps promote a favourable composition of gut bacteria by inhibiting the growth of harmful disease-causing microorganisms. In research studies on mice, it has been shown to combat the growth of pathogenic bacteria and increase the presence of virus-neutralizing antibodies in the gut.

It is commonly used as a probiotic culture to address digestive disorders and gastrointestinal discomfort. It has been shown to reduce colonic inflammation when supplemented in experimental animal models with colitis. Research shows that it can ameliorate the inflammatory response within gastrointestinal tissue by reducing levels of colonic tumour necrosis factor (TNF)alpha and inducible nitric oxide synthase (iNOS).

Lactobacillus Plantarum2019-09-09T18:34:13-05:00

Lactobacillus PlantarumLactobacillus Plantarum is a species of Lactic Acid Bacteria with probiotic effects in the horse macrobiome. Research shows that supplementing with probiotics can improve inflammation, oxidative damage, immune fuction and insulin sensitivity in horses.

DFMs (direct-fed microbials) are commonly used in horses to support digestive function, hindgut health and nutrient absorption from the gut. Lactobacillus Plantarum naturally occurs in the horse intestine and helps to inhibit the growth of harmful bacteria through competitive exclusion.

Equine researchers have also been examining the effects of L. Plantarum on exercise performance in horses. In one preliminary study involving mice, adding this strain of probiotic bacteria to the diet was shown to increase muscle mass and type I slow-twitch muscle fibers. According to the researchers, long-term use of this supplement could “enhance energy harvesting, and have health-promotion, performance-improvement, and anti-fatigue effects.”

Recommended Use: Supports gut health and immune function.

Directions for Use:

Administer with feed. Provide Daily.

Body Weight Scoops Dose
< 200 kg 0.5 scoops 0.5 g
200 – 500 kg 1 scoop 1 g
> 500 kg 1.5 scoops 1.5 g
1 scoop = 1.2 cc = 1 grams


This VHP may not be incorporated into a mixed feed.

Store in a cool, dry place, protected from direct sunlight. Keep tightly closed when not in use.

Not for use in horses intended for food.

Shelf Life:

12 months from date of manufacture.

A blend of 5 strains of pure probiotics.
Nutrients Units
Proprietary Active Blend per gram:
Contains not less than:
Lactobacillus fermentum (min) 1 billion cfu/g
Lactobacillus acidophilus (min) 1 billion cfu/g
Lactobacillus casei (min) 1 billion cfu/g
Lactobacillus plantarum (min) 1 billion cfu/g
Lactobacillus farciminis (min) 1 billion cfu/g
Total Bacteria (min) 20 billion cfu/g

Ingredients: Lactobacillus acidophilus, Lactobacillus fermentum, Lactobacillus casei, Lactobacillus plantarum, Enterococcus faecium, dextrose.

Excipient Ingredients: Dextrose, calcium silicate

Register & manufactured by: Mad Barn Inc., Petersburg, ON, Canada.

Disclaimer: These statements have not been evaluated by Health Canada or the FDA. This product is not intended to diagnose, treat, cure or prevent any disease.
Quantity Days Supplied Serving Size Cost Per Day
60 g
$0.33/ DAY
500 g
$0.27/ DAY
1 kg
$0.24/ DAY

* Based on a 500 kg horse


Price 60 grams $20.00
500 grams $135.00
1 kg $245.00
Scoop Size cc 1.2
Feed Per Day g / 100 kg BW 0.2 g
g / 500 kg horse 1 g
Scoops Per Day scoops / 100 kg BW 0.2 scoops
scoops / 500 kg horse 1 scoop
Cost Per Day $/100 kg of BW $0.05
$/500 kg horse $0.25
Body Weight Calculator
Metric Units (KG)
Age of horse:
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Body Length (cm):
Approx. body weight:
Imperial Units (LB)
Age of horse:
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Customer Questions About This Product

    Can doubling the dose for a period ever beneficial? can it have any negative effects to double the dose?
  1. 0 votes
    Q Can doubling the dose for a period ever beneficial? can it have any negative effects to double th...... Read more
    A Doubling the feeding rate could be beneficial if there are significant gut issues, but we recommend checking in with our nutritionists first. If significant gut issues are occurring, our Visceral+ supplement or our Optimum Digestive Health may be a better option. Doubling the feeding rate is unlikely to cause negative effects.
  2. Safe for pregnant mares
  3. 0 votes
    Q Safe for pregnant mares
    A Hi Deborah, Per government regulations, this supplement has not been tested in pregnant mares and we are unable to advise on the safety or suitability of the product for pregnant or lactating horses.
  4. Can this cause colic symptoms or anything in horse
  5. 0 votes
    Q Can this cause colic symptoms or anything in horse

    We have never had any reports of this type of response.

  6. Has this been known to cause stomach pain in horses?
  7. 0 votes
    Q Has this been known to cause stomach pain in horses?

    No the probiotic has not been reported to cause stomach pain in horses. It is very well tolerated by horses and has no reported side effects.

  8. Can you mix the powder with water to make a paste if horse is not eating grain well?
  9. 0 votes
    Q Can you mix the powder with water to make a paste if horse is not eating grain well?
    A Yes, you can mix the Optimum Probiotic powder with room-temperature water prior to feeding. We do not recommend mixing the probiotic with hot water, as the hot water will kill off the bacteria.
  10. Is Optimum a pellet or a powder?
  11. 0 votes
    Q Is Optimum a pellet or a powder?
    A We have two products under the Optimum line. The first is the Optimum Probiotic which is just a straight powdered probiotic supplement. It contains a pure blend of 5 probiotic strains. The second product is Optimum Digestive Health which is a more comprehensive gut health supplement and contains probiotics and prebiotics. That comes in a pelleted form.
  12. I recently acquired a yearling. At what age you can start them on the probiotics?
  13. 0 votes
    Q I recently acquired a yearling. At what age you can start them on the probiotics?
    A The probiotics can be started at any age. Just adjust the dose to your horse’s body weight.
  14. How does your probiotic supplement compare to Equine Choice's probiotic?
  15. 0 votes
    Q How does your probiotic supplement compare to Equine Choice's probiotic?
    A Optimum Probiotic is just 5 strains of bacteria, nothing else. It's a great probiotic if you are looking for a product with no fillers to add to your horse's diet. Equine Choice's probiotic contains other ingredients besides just bacteria. While you can switch to our Optimum Probiotic, if you wanted to switch to something more like Equine Choice, it would be our Optimum Digestive Health Pellets which is a more comprehesive gut health supplement that also contains yeast, digestive enzymes, prebiotics and more.
  16. I want to order one probiotic at $20. Why do I need to order two to get free shipping?
  17. 0 votes
    Q I want to order one probiotic at $20. Why do I need to order two to get free shipping?
    A Unfortunately shipping costs are so high if we send out one package of the probiotics at a time that we had to set a minimum order of two in order to ship via courier. I’m sorry for the inconvenience!
  18. Is the dosage for Optimum Probiotic given per feed or per day?
  19. 0 votes
    Q Is the dosage for Optimum Probiotic given per feed or per day?
    A The daily dose for our Optimum Probiotics is 1 gram per day, which can be given in a single feeding or split into multiple feedings during the day.
  20. Why is there a minimum order of two 60 gram probiotics to receive free shipping?
  21. 0 votes
    Q Why is there a minimum order of two 60 gram probiotics to receive free shipping?
    A We now ship the probiotic pouches by courier to ensure fast and reliable delivery. This requires us to have a minimum order to keep our prices low and to offer free shipping.
  22. For a senior horse who is having issues with weight would you recommend the Optimum Probiotic or Optimum Digestive Health?
  23. 0 votes
    Q For a senior horse who is having issues with weight would you recommend the Optimum Probiotic or ...... Read more
    A The difference between the two is that Optimum Digestive Health Pellets (ODH) have both probiotics and yeasts, toxin binders, enzymes and more to support total hindgut health. Our Optimum Probiotic just contains our 5-strain blend of probiotics. Both are excellent for replenishing and maintaining healthy gut bacteria so that nutrients are better absorbed and the risk of digestive upset is reduced. It depends on what your goal is with your horse, but for more comprehensive hindgut support, I would go with ODH. It is also important to determine whether there are underlying issues contributing to weight loss. Teeth issues and/or ulcers may be contributing to weight loss. I would also ensure that she is getting adequate levels of vitamins and minerals from her feed by weighing it and reading the feed instructions carefully. I say this because we often find that commercial feeds are not fed at the correct rate (by body weight) and can result in deficiencies long term that can affect many aspects of health, especially in senior horses.
  24. I am trying to decide between the Optimum Probiotic and the Optimum Digestive Health Pellets. Why would I choose one supplement over the other?
  25. 0 votes
    Q I am trying to decide between the Optimum Probiotic and the Optimum Digestive Health Pellets. Why...... Read more
    A Which product to choose really depends on what you're trying to achieve. The Optimum Probiotics are a great product and very affordable for providing everyday digestive support to help enhance immune function or to give before and after worming, antibiotic treatment etc. It is composed of 5 pure live bacterial strains (probiotics) and nothing else. Optimum Digestive Health is a much more comprehensive gut health solution and would be the go-to for horses with ongoing digestive issues or if you just want to improve overall gut health and absorption of nutrients. It has an array of ingredients to improve pre-cecal digestibility of macro-nutrients and improves overall digestibility of minerals. It helps steady the pH in the hindgut, enhances immunity through multiple mechanisms, increases mucin (protective layer in the gut) production and binds toxins.
  26. Are the probiotics provided in a powdered form or is it in the form of a paste/liquid?
  27. 0 votes
    Q Are the probiotics provided in a powdered form or is it in the form of a paste/liquid?
    A Our pure strain probiotics are provided in a granulated powder form. We don't currently offer a pure probiotic supplement in paste form. However, because the serving size per day is so small it is typically not a problem to get horses to eat this product. If you do want a probiotic in paste form, we do offer the Visceral+ paste which contains our Mad Barn 5-strain blend of probiotics along with a number of additional ingredients to support digestive function and gut health.
  28. Does this probiotic contain any prebiotic ingredients?
  29. 0 votes
    Q Does this probiotic contain any prebiotic ingredients?
    A No, the Optimum probiotic powder is a pure probiotic supplement that only contains 5 strains of beneficial bacteria with no fillers or added ingredients. If you are looking for a product that does provide prebiotic fiber, check out our Optimum Digestive Health pellets. Optimum Digestive Health contains, pre and probiotics, along with yeast, immune modulators, toxin binders and ingredients to stimulate growth of cells in the gut.

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