Colitis, like many conditions that affect equines, is common in humans as well. People being diagnosed with Colitis generally have a high-stress lifestyle, a poor diet, or family history working against them, in some combination. This human scenario is very much the case with your average barrel racing horse.

Colitis, like many conditions that affect equines, is common in humans as well. There are a number of factors that are causes of Colitis.
Dealing with a wide variety of feed, extensive travel and the
rigors of competition can be enough to put your performance equine at an increased risk of developing Colitis.

Dealing with a wide variety of feed, extensive travel and the rigors of competition can be enough to put your performance equine at an increased risk of developing Colitis. There are a number of other factors at play that can also bring about the onset of this painful and potentially life-threatening condition.

Like many problems affecting horses, this one starts and ends with their digestive system. This delicate balance requires not just perception and experience on the part of owners, trainers and veterinary staff – it requires a real dedication to stopping problems before they begin.

The right dietary products combined with a keen eye for early warning signs will have you riding tall in the saddle in the race to combat Colitis in your prized equine.

What is Colitis?

Colitis is an inflammation (itis) of the colon (col). The primary symptom is diarrhea. When the colon wall becomes excessively irritated, it stops functioning properly and prevents the proper internal uptake of water. Fluid from the blood stream is often dumped into manure. A person’s digestive system works in a similar way.

Equine veterinarian Keith Latson is well-known on the Southern California Thoroughbred circuit and he has plenty of experience dealing with a wide variety of digestive problems in high-performance equines. While his clients range from some of the biggest named in West Coast horse racing to some up-and-coming barns stocked with hard-knocking claimers, he sees Colitis affect horses of every background and pedigree.

Dr. Latson points to the gastrointestinal tract as the battlefield for Colitis symptoms.

“The equine digestive system is exquisitely sensitive to change. Slight changes in diet, stabling, immediate environment and intensity of exercise can trigger Colitis. Any of those things, individually, can cause a change in flora in the gastrointestinal tract. Understand the risk factors and minimize those. Make your changes slowly so the horse can adjust over time with proper digestive support,” says Latson.

Untreated or poorly managed Colitis can become a career and even life-threatening condition in virtually any horse. Common direct triggers include a reaction to antibiotics received after injury or surgery, while dramatic changes in environment or surroundings can also trigger Colitis.

Latson refuses to mince words when it comes to a topic so important.

“The most severe outcome, obviously, is death. Even with good management we have not been able to save some horses. Early identification and early institution of treatment are requisite. Ultimately, it’s about being responsible and doing the best for your horses.”

In terms of actionable advice, Latson believes that it should be standard operating procedure for anybody working with your equines to know about the signs of a Colitis onset.

“The initial clinical sign may be something as simple as a dull look in the eye. It could be a low-grade fever. Or maybe the horse just isn’t eating well.”

Anybody who has spent enough time in a barn knows that a horse who isn’t cleaning up its feed bucket is a horse with an underlying issue.

“We will perform some specific tests and then we’ll be able to determine if it’s Colitis or not. The tricky thing about Colitis is that it’s part of a category of diseases that all have similar signs. It can take blood work and it can take laboratory tests on manure. Even listening to the intestinal tract can be useful in diagnosis.”

As mentioned before, diarrhea is another major indicator – especially if it appears suddenly.

The Causes

The most common direct causes of Colitis include parasites, exposure to toxins, feed changes and reactions to antibiotics. There are also plenty of direct causes like bacterial infections or even reaction to external stress. Bacterial infections can be particularly damaging in large yards or areas where horses come into contact with many other equines. Salmonella or Clostridium are contagious to other horses and, though herd outbreaks of these diseases are relatively uncommon, the chance of contracting them increases when a horse enters an area like a veterinary hospital. Similar to how infections and disease run rampant in human hospitals, there is a similar issue at play in veterinary environments.

Diet: a horse’s natural environment will see them graze for long periods of time and subsist on a diet that is primarily a high in fibre and low in starch. While a horse’s natural diet in the wild will change based on the season, many horses without access to that type of lifestyle will see sudden and abrupt changes in the quality and content of their feed. Since their bodies don’t get the time to acclimatize gradually, the end-result can be severe stress on your equine and its digestive system. Performance horses like barrel horses, who eat a lot of concentrated (hot) feed, can be particularly susceptible to this because of a limited number of gut inhabitants. Less diverse feed means less diverse intestinal flora (good microbes in the gut). The lower the diversity, the greater the chance for problems.

Antibiotics: often used to treat bacterial infections by either slowing their growth or killing them off entirely, the side effects from a variety of antibiotics can increase the likelihood of a horse developing Colitis. When a horse suddenly develops diarrhea after receiving antibiotics, it is a clear indicator that they have lost a portion of the normal bacteria that helps them through the digestive process.

Latson described this as akin to a battlefield within your horse’s gut. “Within the intestinal tract, there is a balance between beneficial bacteria and their ability to keep harmful bacteria at bay. The harmful ones can take control and release toxins to kill beneficial bacteria.”

Parasites: can be counted on to cause inflammation in the intestinal tract. This can lead to a variety of negative symptoms – many of which raise a horse’s risk of developing Colitis. Fluid loss, improper digestion, anemia and general weight loss are all symptoms that may arise from a parasitic infection. Many of these parasites are unique to equids and can include anything from generic intestinal worms to blood parasites such as Potomac Horse Fever.

Toxins: many of the products used in and around barns and farmland in general can trigger adverse effects in many equids. While much of the symptoms will vary on a horse-to-horse basis, the stress resulting from exposure to toxic material can have severe implications on their digestive tracts.


While a veterinary professional must conduct a proper diagnosis, time is of the essence as soon as you notice symptoms of Colitis or related affliction. Since diarrhea is oftentimes the first visible sign of something wrong, a steady supply of fluids and electrolytes are required to offset the threat of severe dehydration.

Once a veterinarian arrives on the scene, they can administer anti-diarrheal medications similar to the pink stuff you pull out of the medicine cabinet after your third round at the buffet. Expect anti-inflammatory drugs and the use of plasma – which is vital in staving off endotoxemia, sepsis and it’s associated bacteria.

Different veterinarians have different approaches to diagnosis of Colitis, but a clinical examination is always the best place to start. Oftentimes, a vet will measure the horse’s electrolyte and pH balance. Expect several tests that will help give clear results about the amount of blood returning to the heart and the ability to distribute blood to the system.

Lowering Risk

Probiotic products are gaining popularity during the treatment phase and they can be a particularly smart option for those looking to lower an equids risk of developing Colitis. Probiotics are live microorganisms that bring great benefits by improving the intestinal microbial balance of any horse.

Probiotic products are also marketed to humans in the form of yogurts and other dietary supplements – perhaps you’ve seen a few ads for them on television.

Like any natural health product, it is a buyer-beware situation.

“Probiotics are a huge category of yeasts and bacteria and not all are created equal,” said Latson. The key, he said, is to find one that passes through the acidic stomach environment and that makes it to the large intestine. He also emphasized the need to find the right concentration. “Many probiotics don’t actually have the appropriate concentration or activity to modify the effects of Colitis. If you don’t do your homework, you may be throwing away money and not helping your horse.”

Consulting directly with your veterinarian can help you make the right choices for the health of your equine.

Oftentimes, a healthy horse with a strong natural flora in its system has a dramatically lower chance of contracting Colitis-causing afflictions from neighbouring horses. The secret weapon is a combination of beneficial bacteria, yeast and protozoa in your horses gut.

“Horses are hind-gut fermenters,” said Latson. “They depend on these microorganisms to convert the plant material to usable energy. Without a steady source of plant material, the horse’s body starts depending on its own tissues for energy. This is one of the reasons why horses with heavy stress will start to lose weight.”

Getting the Probiotic Balance Right

Oftentimes, a healthy horse with a strong natural flora in its system has a dramatically lower chance of contracting these Colitis-causing afflictions from neighbouring horses. The secret weapon is a combination of beneficial microbes from good, well-formulated probiotics in your horse’s gut.

Rob Franklin knows his way around probiotic products for competitive equines as an Internal Medicine specialist in Weatherford, Texas and as the current President of Texas Equine Veterinary Association. Franklin says the decision of which product is better can be compared to something as simple as a regular cup of morning coffee.

“It’s like any product, when you’re not familiar with it you might be willing to settle for whatever is there.”

Franklin pointed to two specific factors that should guide your decision-making when considering probiotic products for your horse’s diet.

“What I try to tell people is that probiotics are living things. There are two issues that you should look at – the first one is how much probiotic to use. Concentration is a big deal – we’re talking about trillions and trillions of microorganisms we are trying to impact. You have to read the label. You need to know the CFU (Colony Forming Units) levels,” says Franklin. (Colony Forming Units or CFUs is geek speak for the strength of the probiotic formula.)

“The best product on the market right now has 100 billion microorganisms in it – more than any other product on the market,” adds Franklin.

It’s also important to pay attention to the type of probiotic being used in a given product. Not every probiotic organism is created equal – some are best used to treat certain conditions under certain circumstances.

This weighs heavily into Franklin’s decision-making when deciding on product formulations.

The negative effects of Colitis can wreak havoc on the physical and mental health of any equid. While the affliction may be caused by a variety of different internal and external factors – some you can control and some that you can’t – probiotic products serve as the first line of defence and can provide an edge in those situations where changes in feed or environment might trigger a Colitic reaction. Think of probiotics not just as a gut stabilizer, but as an extra weapon in the ongoing fight to keep your horse in top-notch condition.

Rob Franklin, DVM, DACVIM and Keith Latson, DVM, DACVS developed FullBucket Equine and Canine digestive care products to address the needs of their clinical patients and performance horse clients. During a volunteer veterinary trip to Veracruz, Mexico in 2011, the two veterinarians distilled their vision of helping undernourished working animals in undeveloped regions achieve improved health and well-being through FullBucket’s Care+Care Initiative: for every serving of supplement sold, a serving of supplement specifically developed for the region is given to animals in need. To learn more about FullBucket Digestive Care products and the Care+Care Initiative, visit


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