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Digestive Health

Wild Horse herd showing the arid terrain

Photograph Nancy Florence, Pine Nut Wild Horse Advocates

Microbiome tests

When the nerves and the muscles of the intestinal tract are functioning optimally, and when the diet is high in fibre, in our experience there is no need for microbiome tests.

Correcting the diet with emphasis on the suitability of forage should be priority to ensure optimal functioning of the whole digestive tract. Inefficient peristalsis influences hind-gut flora populations as well as lack of diversity and/or fibre in the diet.

Bio-Diversity – a ‘double-edged’ sword

Bio-diversity in their diet IS desirable so hay cut from pastures containing a variety of grasses is healthy but allowing uncontrolled access to pasture swards in their vegetative state, which contain more than a scattering of plants like plantain and legumes like clover, is the CAUSE of many of the health problems of modern day horse.

Because our domestic horses are living on fresh green grass for most of the year and therefore don't have to move far to get to it, they are already ingesting too much potassium and nitrogen so adding fresh herbs for biodiversity is adding to this load.

Sowing 'meadows' which include grasses, legumes and herbs, sounds idyllic but remember, the horses diet needs to be sparse and diverse - not prolific and diverse. Too much potassium and nitrogen has an adverse affect on the gut flora.

When forage is excessively high in both potassium and nitrogen, it becomes a 'fertiliser' to the flora in the gut causing rapid population explosions of opportunistic, pathogenic organisms in the gut .

"Potassium promotes the overgrowth of saprotrophic (micro-organisms that normally grow on dead matter), commensal (organisms that live together but don't harm each other) and pathogenic (microbes that cause disease) micro-organisms in plants, especially plants damaged by droughts, frosts and freezes.

Thus, such forages become the source of many opportunistic, potentially pathogenic bacteria and fungi.

​After ingesting them, livestock face an overgrowth of opportunistic, pathogenic organisms in the gut. The organisms rapidly proliferate to produce toxic by-products, like excessive ammonia, which is acutely toxic to foetuses and the immune system.

​These pathogens infect not only the foraging animals but their foetuses. Early and mid-term foetuses may abort, while near-term foetuses may suffer premature birth, and/or septic weak neonatal birth.

Similarly, it's felt that high-potassium forages encourage excessive growth of endophytic and other pathogenic fungi, especially in Fescue and Rye Grasses. The toxins these fungi produce add to the reproductive problems in cattle and horses."
T.W. Swerczek, DVM, PhD

So to correct problems, in our experience, we take these out, not put them in.

​Fecal Water Syndrome

This is where the form of the manure balls is solid but there is accompanying liquid with defecation. Or fecal liquid can be passed any time without the presence of solid manure.
This ‘dribble’ soils their hind legs and tail and is unpleasant for horse and owner. In our experience it is a sign of a problem with the functioning of the vagus nerve and peristalsis (gut motility/inflammation) and is rectified relatively easily by feeding Alleviate Gold.

Since implementing management strategies outlined here, we have very few, if any issues with gut health. 

The slowing down of the passage of food alters the internal environment for the gut flora, precipitating changes to the microbiome.

Avoiding Digestive Issues

Chew Time:

The horse is designed to eat for 16-18 hours per day. This means he is chewing and producing saliva for most of the day. Saliva contains a ‘buffer’ which helps maintain the gastric juices at exactly the righ pH to begin the breakdown of the coarse, fibrous material which should make up the majority of his diet.

​This is why long periods without food (more than 4 hours) will cause the pH of the gastric juices to drop.

Many horses subsist on forage which is not supplying the constant stream of coarse, fibrous material causing them to be lacking chew time.

Examples of this are:

Nibbling  grass through a grazing muzzle
Short, green grass

Longer, mid-mature soft green grass

Running out of food for periods of 4 hours or longer eg: while traveling or having insufficient hay.


An 'Over-looked' Cause of Gut Problems!

Shania’s 25 year old mare 'Zoe' developed dreadful diarrhea around the beginning of March. On and off she also had a noisy, rumbly tummy.

Shania sought veterinary attention and her fecal samples came back clear (after checking for salmonella and other nasties).

Back then she was put on hay, a small break of short green grass at night with a hard feed of lucerne chaff, grain free and fixine. A salt/mineral block was available in her paddock. But over two months later there was no improvement to her manure status and it was becoming increasingly 'watery'.

Shania would spend hours repeatedly cleaning her up!

Then late May she went completely off her feed (very unusual for her) and started going downhill from there. With Zoe being 25 years old this was naturally a major concern and this is when Shania contacted us:

"Hi there, I have a mare whom I am struggling with and have been recommended to contact you. I have included a photo below of the problem we are having, can you recommend anything that might help?"

*Note the bloods came back with low protein and inflammation both to be expected with diarrhoea but no infection. Her fecal sample was clear also.

May 26th: We recommended that Shania start syringing in a tablespoon of AlleviateGold every 2 – 3 hours along with this we introduced beet and crushed linseed mixed into Timothy chaff. We also took out the Lucerne chaff and the grain-free.

May 27th: “She’s doing better, is eating, is more alert and her poo has more consistency to it.”

When the AlleviateC/SOS arrived Shania added a tablespoon to each syringe.

May 30th “Two semi normal poo this morning for the first time in months!! Super happy hopefully she keeps improving”

June 2nd “Tummy rumbling seems to have settled today.”

Around June 6 – 8th she actually regressed for a couple of days with the diarhoea returning (not as bad as before) so Shania increased the AlleviateGold again

June 15th Shania messaged us with the following…“I can only hear her gut noises when I put my ear next to her belly (normal).

Her poo is looking really good and healthy and she is back to her normal self – much more alert and active. I am so happy with the improvement.

Thank you so much for all your help and expertise, such a relief that she has come round. Especially seeing as nobody else had any answers at all!!!!

It sure has been a big learning curve for us. What would you suggest our next plan of action be? She’s still on no grass with hay & hard feed…”

We recommended that Shania reduce the SOS & Gold to half the amounts and monitor. Plus to start giving her 10 mins am & pm access to nice long grass, obviously introducing it very carefully.

The photos below show the improvement in her manures!

With no sign of infection and her fecal tests clear we believe the reason the AlleviateC/SOS and the AlleviateGold worked for Zoe was because they restored the normal function of her digestive tract which must have become sluggish.


If the smooth muscles (which need to contract rhythmically)to push the food through) slow down then the digesta over-ferments and excess gas builds up creating the loud gut noises and discomfort.

This in turn changes the internal environment of the hind-gut which upsets the balances of the various populations of flora making up the microbiome.

Addressing this aspect along with CAREFULLY changing her diet to 100% hay allowed the flora populations to restore. Note no pre or probiotics were used to this point. In our experience it is best to get the gut functioning properly first to make sure the environment for the microbiome is conducive to their health – or for some of them, survival.

We checked that Zoe's dentition was good and we were careful not make any sudden changes to her diet.

It is critical to call your vet to persistent diarrhea in order to rule out other potential causes that could be life-threatening.

If you need help for your horse, in order for us to have all the info we need to make recommendations, please feel free to contact us via our new web form...


See also the case where ulcers were suspected because of Aggression issues...


Zephyr happily munching high fibre mature grass. PHOTO Cathy Dee

The Importance of Forage


In the vast majority of cases digestive issues are indicative of
- inappropriate basic forage

-Disturbance to normal gut function due to sub-optimal vagus nerve function

Inappropriate forage not only directly affects the balance of the hind-gut flora populations but also indirectly by causing the mineral imbalances which affect the entire metabolism.

Metabolic inefficiencies can be caused by a deficiency in any of the micronutrients, which can also be induced or exacerbated by a variety of chemical, metal, or environmental toxicities.

The Chicken or the Egg?

The Significance of the Vagus Nerve!

Mineral imbalances which affect the more obvious neuromuscular system, will of course also affect the vagus nerve (the major nerve which innervates and controls the entire digestive tract plus the internal organs).

The first thought for treatment of digestive issues typically focuses on enhancing gut flora with pre or probiotics in order to promote ‘good’ bacteria over ‘bad’. This would seem a logical approach but which comes first - the chicken or the egg?

Gut dysfunction can be a symptom of an underlying metabolic issue which is causing a problem with the nerves and muscles of the gut.

The vagus nerve is one of the MAJOR nerves in the body. It is critical that it functions optimally because it is responsible for the regulation of ALL internal organ functions digestion, heart rate, and respiratory rate, as well as the constriction or dilation of blood vessels, and certain reflex actions, such as coughing, sneezing and swallowing.

​The vagus nerve connects the brain with the ‘gut brain’ and plays an important role in the toning down of inflammation,  maintaining intestinal and energy homeostasis, regulating food intake and satiety.

The efficiency of the vagus nerve is determined by nutrition and can influence food intake and weight gain.

Significantly, the vagus nerve plays an important role in the control of emotions and other stress-induced and inflammatory diseases.

Any mineral imbalances that adversely affect the brain and nervous system, are automatically also adversely affecting the vagus nerve.

If the vagus nerve is not working optimally, peristalsis (the involuntary constriction and relaxation of the muscles of the intestine creating wave-like movements that push the contents of the intestine forward) can either slow down or even stop altogether (Colic).

Gaseous Colic

The slowing down of the passage of food alters the internal environment for the gut flora, precipitating changes to the microbiome.

The food sitting in one place for too long causes overfermentation resulting in excess gas which is evident by louder than normal gut noise.

Normal gut sounds (borborygmi) are caused by the peristaltic movement of the intestines which should contain a mix of gas, water and feed. Rumblings and gurgles are normal in healthy horses, and suggest proper function of the gastrointestinal tract (normal motility).

​Any time these gut noises can be heard from a few metres away, is a significant cause for concern because it signals the over-production of gas which will cause discomfort and the danger of colic if part of the inflated intestine floats up and wraps around another part of the internal anatomy.

​It is far better to target the cause rather than the symptoms.

Gaseous colics are common any time there is a surge in grass growth (Spring/Autumn)

Leaky Gut Syndrome

This is also a downstream result of disturbances to the optimal functioning of the vagus nerve. The entire intestinal tract has a single cell, epithelial lining, and the junctions between these cells need to be TIGHT to prevent 'leaky gut' syndrome occurring.

When the vagus nerve is not operating at full efficiency, these junctions become loose and there is increased intestinal permeability, allowing molecules through that wouldn't normally enter the blood stream.

​Gastric Ulcers

Either the horse’s basic forage is not high enough in fibre, or it is not supplied to the horse such that he does not go more than 4 hours without food.

Being ‘girthy’ and ‘twitchy’ can be due to the presence of gastric ulcers OR the result of a disturbance to normal nerve function. The horse’s skin is densely populated in nerve endings and certain nutrient/mineral imbalances cause them to be hyper-sensitive or ‘twitchy’ where they show obvious adverse reactions to being touched, brushed, saddled, girthed up or covered.

This is why it is necessary to verify the presence of ulcers by scoping, then omeprazole products can be administered for a short period of time - 1 month, to facilitate healing.

Symptoms of Gastric Ulcers

  • Showing signs of discomfort – girthy, grumpy.

  • ‘Twitchy’ (hyper-sensitivity of the skin)

  • Going off their feed

  • Losing condition

  • Reluctance to work

  • Wind-sucking

  • Bad coat

  • Colic

The main indicator that horses have ulcers is that they go off their feed.

(Physiology, Gastric Intrinsic Factor Hashim M. Al-Awami; Avais Raja; Michael P. Soos).

How MUCH HAY to feed?

When horses are confined to a dry lot or a track, or have run out of grass to eat because it has been nibbled down to nothing, you need to make sure they have continuous access to forage in the form of hay. If you go out there in the morning and there is not a skerrick left then best to give them more!

Continuous access not only keeps horses contented, it ensures the ‘chew time’ necessary to precisely buffer the stomach acids and prevent ulcers forming.

Plus it supplies the fibre needed to feed the flora in the hind-gut. Billions of micro-organisms who thrive on the comparatively low nitrogen, low potassium, low sugar and starch, coarse, fibrous material that makes up mature grass or hay.

For a horse, chewing is part of his ‘psyche’ – all is well with his life when he is chewing fibrous plants!

Short grass of any species or description, green or brown, doesn’t provide the necessary chew time and neither does it provide sufficient fibre to feed the flora and then the flora can’t feed the horse.

If there isn’t enough fibre in the fermentation vats of the hind-gut, no heat is produced by this process and there is no fuel to fire their internal heater to keep them warm over winter!

The ‘slice in the morning and 2 slices at night’ regime is simply not enough to keep the hind-gut flora nourished, not to mention it increases the likelihood of stomach ulcers developing. A person can buy a lot of hay with the money spent on ulcer treatments.

For some horses it is a balancing act to supply continuous hay without weight-gain, especially those horses who hardly take a break from it! Fixing this requires a ‘reverse psychology’ type of approach. These horses have become obsessive gorgers because their internal metabolic processes have adjusted/adapted to not having enough!

The way to return your horse’s metabolism to normal is to make sure he never runs out! Once he realises there is ALWAYS hay there AND once his metabolism has had time to respond accordingly he WILL BE ABLE TO slow down, eat for shorter periods and feel satisfied.

Persevere with this as for some horses this will happen within a few weeks but for others it can take longer for his physiology to adjust. This is why it may take months before some horses start to self-regulate again.

Adhering strictly to 1.5% of BW can leave the poor horse without food for too long. Especially small ponies who only weigh 200kgs or less – 3kgs of hay, even the 4kgs which would supply a maintenance amount of 2% BW can be gone in no time flat!

Forage restriction ISN'T the answer and in fact it is very stressful physically, mentally and emotionally. Equine Metabolic Syndrome (EMS) is a metabolic disorder as opposed to just being over-weight. Adlib availability of forage along with proper nourishment and plenty of movement is the key to managing horses with EMS and prevention of it developing in the first place.

Avoid Lucerne or hay with any clover, they contain far more calories per kg than grass hays even though they can be lower in sugars.

Small mesh hay-nets encourage trickle-feeding. Some owners go to great lengths to ‘stretch out’ consumption, hanging them from posts or trees, attaching them to an anchoring tyre, or stretching a small-mesh net over a box. There are some great ideas out there – just always check for safety in your situation!

Hay can be soaked to reduce its nutritional value while still providing the fibre - then the horse can consume more of it over the 24 hour period. Daily essential nutrients can easily be supplied in a small daily feed.

For some over-weight horses it can work to substitute at least some of their hay with straw. Being higher in indigestible lignin it is harder to chew and tends to slow them down. Mix with grass hay to extend feeding times and satisfy the need for chewing.

Obviously straw shouldn’t be fed to horses with poor dentition and make sure water is readily available. In most cases late-cut grass hay is preferable.

The take home message is: Budget for feeding appropriate quantities of hay. The benefits are endless and it is the most economical strategy in the long run!

It Pays Not to Mess with Gastric Acidity

Nowadays horse owners place a big emphasis on their horse’s gut health. Rightfully so.


This includes taking steps to avoid their horses developing gastric ulcers, and also not upsetting the microbiome of the hind-gut.


There is a lot of speak around ‘buffering’ stomach acid. Terms like aids gastric buffering, or has a buffering action unfortunately inadvertently makes it easy to get the wrong idea - that the stomach ACID is the culprit and that stomach acidity is somehow ‘bad’.


This arises from the fact that:
-  to heal stomach ulcers the production of stomach acid is blocked by proton-pump inhibiting products – omeprazole.
-  and from recommendations to feed products which buffer the stomach acidity (act as antacids making it less acidic). These are calcium type products or Lucerne/alfalfa. (NB – feeding Lucerne to horses already on cool season grasses/clovers can cause other health and behaviour problems)


Here are some points to understand before feeding or administering products which alter your horse's stomach acid:

Stomach acid evolved to be very acidic (pH 1.5  - 2.5) for several extremely important reasons...

  1. A VERY ACIDIC environment in the stomach is needed to activate the enzyme pepsinogen; the principle enzyme which starts the breakdown of protein.
    It is vital that this process happens right there in the stomach, before the food moves out and into the small intestine in order to prevent the unintended digestion of, and therefore damage to, the protective proteins which line the rest of the digestive tract.

  2. Gastric acidity (pH 1.5 – 2.5) kills most bacterial pathogens that are inevitably ingested with food. If the potency of gastric acid is compromised by items which tend to block stomach acid production (proton pump inhibitors such as Omeprazole, antacids or other products which have a buffering/neutralizing effect on the stomach acid), then the horse is more susceptible to diarrheal diseases from pathogens like salmonella.

  3. The strong acidity is necessary for production and function of ‘intrinsic factor’ - a substance secreted by the stomach which enables the body to absorb vitamin B12.  Lack of intrinsic factor leads to lack of Vitamin B12 in the blood which has serious consequences on blood chemistry and precipitates a variety of neurological disorders.

These are critical reasons why gastric medications for ulcers should be used SHORT TERM for their purpose, and then discontinued. It is also why buffering products should not be fed routinely.

In our experience, we would not recommend feeding lucerne/alfalfa for the purpose of preventing ulcers due to the potential for other undesirable consequences.

 In order to prevent ulcers forming without inadvertently causing other problems,  ensure your horse always has access to adequate fibre in the form of mature, stalky grass or hay. This ensures both maximum chew time (See Post on June 16th How Much Hay to Feed) and the presence of the fibrous mat that ‘puts a lid’ on gastric juices in the stomach thereby preventing harmful splashing.

The pH of the rest of the horse's digestive tract is not designed to be so acidic. In the hind gut the pH needs to be closer to 7 (neutral) to create an environment suitable for the live microbes to be able to live)

The prevention of ulcers is always better than the cure!


Influence of Gastric Acid on Susceptibility to Infection with Ingested Bacterial Pathogens
Sharon M. Tennant,1 Elizabeth L. Hartland,1,2 Tongted Phumoonna,2 Dena Lyras,2 Julian I. Rood,2 Roy M. Robins-Browne,1,* and Ian R. van Driel3

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