Thursday, August 8, 2013

Does my vet know?

by Maksida Vogt, Natalija Aleksandrova

In these times as we are becoming increasingly educated on different aspects of the health of our horses, and animals in general, quite a few situations arise which cause us to think deeper about the knowledge and treatment options that veterinarians apply to our animals. This article is not meant to be an affront to the knowledgeable and responsible up-to-date veterinarians. The sad fact however is that we routinely encounter a pattern that an international majority of veterinarians display. The pattern is a lack of knowledge about horses biologically correct keeping, about illnesses connected to biologically wrong keeping, about the natural normal behavior of these animals inside of and outside of their biological niche, as well as treatment of simple infections and abscesses related to their biological niche requirements being disregarded.

This problem is not connected to any particular country. In fact, we watch it happening in many places, as our organization receives feedback from horse owners of different countries, and our professionals encounter it on an ongoing basis everywhere as well. It seems this is a general problem. With this article we would like to encourage horse owners to never be afraid of questioning the proposed work of veterinarians and the health of their horses.

The scientific thesis by Dr. Cook, which conclusively proves the harm of the bit in the horse’s sensitive mouth, has already been in print and available for YEARS, it is however yet to be included in veterinary school syllabus, and is largely unknown by vet professionals. The bit is a foreign body laying on the mucosal tissue and the nerve endings of the jawbone. In the mouth of a horse the presence of this foreign body, alone, triggers the chewing reflex, and the horse starts producing saliva. Influencing this foreign body in different ways via the rider’s hand causes neurological discomfort and pain. We have an amount of photographs documenting the damages caused by bits, starting from bruising up to and including severe tissue trauma of tongue, soft palate and damaged mandibula, problems with teeth. These documented proofs were published in scientific magazines and to date remain unopposed, yet veterinarians still do not use this knowledge in their practice and do not educate horse owners regarding this problem. This leaves room for speculation on the quality of their knowledge and also on possible reasons that might influence their lack of action.

Especially regarding hooves – most veterinarians lack up-to-date knowledge on diagnosis and correct treatment options. Here we would like to present several cases of incompetency in the diagnosis and treatment of different hoof problems, which we collected from horse owners and our practice.

Case 1. A wrong treatment of hoof problems by a team of veterinarians and a farrier

A mare 19 years of age, was rescued and arrived with a so called „orthopedic“ shoe on one of her front hooves. The treatment was for ‘hollow foot’ (‘white line disease’ with the wall separation), a problem which she had had for years. The mare was a competition show jumper with this foot — an unbelievable fact, which gives us another serious reason to question the existence of equestrian „sport“ and people who are in it and who support it. The owners/rescuers were told that this problem was ‘nothing special’, but in reality the hoof could not keep even a shoe on anymore. The mare needed to be transported to a clinic at Telgte. At this clinic a farrier pushed a nail into the hole in the hoof wall to see how deep it went, a softer object would have sufficed. Then he performed a hoof wall resection, removing a large section of the dorsal part of the wall.



The mare was sent home with a bandaged hoof and with a plastic pad underneath serving as „protection“. It was advised that the mare was to be kept confined in a box rest situation. The mare spent one year in the box. Her bandage was renewed every few days. Everything was done exactly as prescribed by the veterinarian team. The owners followed their advice in the belief that the team knew what they were doing and that they were in fact helping this mare. The owners made considerable efforts to give the mare more space in which to live in her Solitary confinement by offering her the space of two boxes and a small paddock. After the year, when nothing had improved and the hoof wall still remained separated, the owners decided to reject further advice from this team of vets and farrier and to search for another solution. They decided to let this horse out of the box so that she could move freely together with the herd. Their decision proved to be a sound one as they observed over time that this free movement situation alone contributed to the improvement of her hooves and better growth of the hoof wall.

Case 1. Analysis

Despite the wide spread believes, bacteria and fungi do not create any threat to the white line of a healthy hoof, since in the healthy situation the rate of horn production always exceeds the rate of its decompression. Bacteria and fungi are always present in any hoof, they are necessary to the hoof. When a healthy balance exists, fungai and bacteria are an integral part of the natural self-trimming mechanism of the hoof. (more: “Hoof thrush” >>).

The true cause of white line problems actually lies in incorrect hoof form and/or in shoeing and/or in improper horse keeping conditions, which restrict horse’s movement, cause hoof dehydration and horn damage via exposure to ammonia. The incorrect hoof form and/or shoeing and the lack of natural movement lead to reduced blood circulation as well as mechanical damage of the corium, which is the tissue that produces white line horn. These causes also lead to damage of the white line itself. Through the damage and poorer quality and quantity of the horn produced, the speed in which the horn is decomposed begins to exceed the speed at which horn is produced, and the white line is thus destroyed far up into the hoof capsule. The space now existing where the white line has been destroyed allows foreign bodies and infection to enter the interior of the hoof. Also the normal populations of bacteria and fungi, explode ‘out of control’ and they move deeper inside the space, ‘eating up’ the horn. If the hoof continues experiencing reduced blood circulation, and damaging mechanical forces continue affecting it, the laminar corium and the laminar horn get eventually affected, and the ‘hollow foot’ effect appears — the wall starts separating from the sole and the coffin bone.

In this situation, shoeing or so called ‘orthopedic’ shoeing can only mask the problem for some time as it remains the obstacle to healing, while the damage will continue progressing, often unnoticed by horse owners and professionals. Because, through restricting the hoof mechanism*, shoeing blocks the blood circulation in the hoof and creates damaging mechanical forces.

*(hoof mechanism >>)

The wall resection also doesn’t address the true cause, as its purpose is only to remove a part of a hoof ‘affected by bacteria and infection’. Quite contrary, the resection can create a situation where infection now severely affects the inner tissues and structure, as the hoof is cut open. Bandaging material and the placement of an artificial wall can create more damaging pressure on the corium tissues.

And the worst advice that can be prescribed in a situation such as this — when a hoof problem is caused by a lack of blood circulation, amongst the other — is putting a horse on the stable rest. It is a basic natural fact — healing can only happen through increased metabolism, i.e. through increased blood circulation. As “fresh” blood supplies a damaged area with nutrients — ‘building blocks’ needed to renew damaged tissue. The more intensive the circulation, the faster healing can happen. To put a horse on the stable rest means to reduce the circulation in her hooves, as the normal circulation in the hooves is only possible through the constant movement that the horse’s body and hooves are created for. Thus, restricting the circulation, we restrict the healing process.

Additionally, separating a horse from a herd, delays the healing process through resulting mental suffering and psychological imbalance. The horse is a herd animal and its brain has different capabilities than the brain of a solitary animal. The horse’s cerebral cortex is built to function normally giving normal correct orders to subordinated brain centers only when the horse lives in a herd.

First, what any veterinary practitioner should recommend in a case of white line problems is physiologically correct hoof care in proper keeping conditions providing unrestricted movement, which would promote the hoof mechanism and, through it, all the healthy hoof functions which are designed to promote healing.



Case 2. Wrong diagnosing and treatment of hoof problems by a veterinarian

A veterinarian was called to a mare who had been found lame in her right front leg the previous night upon returning from her paddock. The mare’s hooves were quite overgrown, and she was scheduled for a trimming session in a few days time. The mare had had her shoes taken off less than 2 months before and was sensitive on hard ground. The vet checked her lame foot and told the owner that the lameness was caused by laminitis in her right front because she had eaten too much grass. The vet took an x-ray of the one hoof, and from this evidence his next verdict was: 'O.k., no coffin bone rotation visible. It is not laminitis.' Though he still believed that the problem making the mare lame was in the hoof. The mare received painkillers and anti-inflammatory drugs and was put on a box rest. Two days later the mare walked normally, and was taken by her owner to the paddock and her herd, as she was becoming quite crazy staying inside alone.

Two days later there was still no visible lameness so the mare was trimmed. Day after trimming she was lame in her right front again. The vet came and concluded 'Laminitis'. He prescribed full rest, pain-killers and antibiotics. The mare stood all the time without putting weight on her right front foot. Loading her left front foot was not a problem. When walking she seemingly didn't have a problem in weight-bearing on her left front foot, but was limping on her right front foot. The owner couldn't agree that it was laminitis causing the lameness, and decided not to give all the prescribed medicine before she could feel sure of the diagnosis. Hoof care professionals in this stable also didn't agree it was due to laminitis, they believed it was rather more likely to be an abscess.

After a few days of the full rest, the owner took the mare outside for a short time. The mare was happy to move freely and trotted, though still lame. A day later the owner couldn't bear to see her horse suffering from separation anxiety from her herd and so she let her lame mare out into the paddock for night. The next day the abscess burst out in the area of the coronet. In a few days the lameness disappeared fully. The owner called the vet to inform it was the abscess. But the vet didn't agree the physical evidence. He still insisted it was laminitis in the right front. Later the owner got a bill from the vet, it stated on the bill 'Signs of the rotation of the coffin bone in the right front hoof visible on the x-ray. Diagnosis: laminitis.' (We remember that the owner was said 'no coffin bone rotation' in the beginning, don't we?)

Case 2. Analysis

Laminitis usually affects both of the front hooves or all four hooves in horses. The acute form of laminitis is characterized by pain a horse shows in all affected hooves. Laminitis can happen without pathological changes inside hoof capsule such as coffin bone rotation. In severe cases, the bone rotation can appear, but not before 48 hours after the signs of pain appeared.

The x-ray made the day after the signs of acute laminitis had appeared cannot be used as a confirmation of this diagnosis: it is too early for the changes to become visible. The changes visible on such x-rays can be the result of previous problems. X-rays may never show any changes, since the acute laminitis can happen without them.

Next, what might make us suspicious about the diagnosis 'laminitis' in this case is that it was diagnosed only in one hoof. It is extremely rare that a horse develops laminitis in only one hoof. So far the only conditions recorded under which such type of laminitis could occur: being a sequelae of excessive weight placed on a limb due to an injury to the opposite limb, when the horse is not allowed to move after being injured ('static laminitis', Rooney, J.).

Another statement, which contradicts the diagnosis 'laminitis in one hoof', is 'the mare got it because of eating too much grass'. All four hooves are ONE metabolic organ of the horse's body. The carbohydrate overload, which causes an effect in the body similar to intoxication, cannot affect only 1/4 of one metabolic organ in our case.

Now we look into the hoof shape of both of the mare's front hooves.


(Click to enlarge.)

We notice the same considerable degree of dorsal wall flaring in both front hooves, the flaring suggests to us a seriously compromised laminar connection similar for BOTH hooves. Having the same degree of damage of the lamina of both front feet, it is very unlikely laminitis could be triggered only in one hoof.

Knowing only these few facts could make us search for another explanation of the lameness in one hoof.

The horse was unshod not so long before the described events. De-shoeing can restore the hoof mechanism in the hooves to some considerable extent. With any restored hoof mechanism, the blood circulation is consequently also improved inside the hooves. With better blood supply, it becomes possible for the body to start repairing the damage, including cleaning the hooves from necrotic tissue, that was caused to the inner hoof tissues by the period of long time shoeing. Abscessing is a method the body uses to remove fragments of dead tissue, which are too big to be removed within the blood stream.

In this case lameness returned in all its strength directly after trimming. Removing the overgrown horn via trimming improved the hoof mechanism even more. Improved hoof mechanism means improved blood supply and thus improved healing capacity. The abscess, previously suspended in its function due to lack of blood supply was supplied new strength for resolving its work after the blood supply of the affected area was improved. Abscesses are supplied from the blood with all the tools they need as their work materials such as white blood cells. The better the blood supply, the more intensive a healing abscessing process can be.

This is why abscessing is not rare after de-shoeing and can appear right after just a planned trim.

Now we look again into hoof photos.


(Click to enlarge.)

If we look closer, we can notice 'seedy toe' in the right front hoof — the 'hole' in the toe. The constant pressure of the coffin bone tip into the sole due to an incorrect hoof shape (too high heels), combined with the pressure from the shoe clip lead to damage of blood vessels in this area and later to bone tissue destruction. Dead tissue from the bone and the corium was accumulating for a long time in this area. The damage in the horn created an entrance for infections from the outside. This creates the perfect situation for an occurrence of abscesses.

And if we look at this photo:



We can see the place, where the abscess eventually broke out at the coronet. It happened directly over the damaged spot in the toe. This is very typical behavior of abscesses — to find the shortest trajectory for exit through a more elastic horn, such as the laminar horn. Abscesses tend to come out at junctions of softer and harder horn.

(More on hoof abscesses >>)

Case 3. Unacceptable quality of x-ray shots made by a veterinary specialist and further mistakes in diagnosing hoof problems using the x-rays

A vet was called to an 18 year old gelding to make x-rays of his front hooves. The gelding had been shod for many years and de-shod a month previous to the visit. The x-rays of the front hooves were required by a hoof care professional for judging hoof conditions after de-shoeing. At the time of making the x-rays, the hooves looked like this:



These are the x-rays that were made for this case:




From the note the vet sent to the owner along with the shots, we learn amongst other things that '...the spacing between the hoof wall and the coffin bone seems to be bigger in the horse's right front hoof than in his left hoof, and this may indicate resorption (a loss) of the bone.'

Case 3. Analysis

The first and the very important problem, which the increased space between the bone and the wall indicates, is chronic laminitic changes inside the hoof capsule: damaged and weakened laminar corium, rotation with separation and sinking of the coffin bone. Even so that laminitis usually is presented in both front hooves, the degree of change can be different in each hoof due to differences in the shape of each hoof.

For the interpretation of bone loss alone to cause a visibly larger distance between the bone and the wall, it would have to be really dramatic bone re-modeling, which we don’t see in the bones on these x-rays. If the statement was to be correct then the kind of bone re-modeling the vet was talking about usually creates a specific shape in the dorsal surface of the coffin bone, making the extensor process look bigger, more pronounced than normal because, due to specifics of the hoof anatomy and physiology, it is not affected by the damaging pressure, which causes the bone loss in the dorsal surface of the coffin bone. We don’t see this specific shape in either bone on these x-rays.

The diagnosis states that only one bone is affected and that supposes a different degree of the remodeling to be shown in each bone, we don’t see such difference on these x-rays.

First what we actually notice about these x-rays is that their quality is unacceptable. They are unacceptable because no hoof soles are visible on them and the lowest part of the x-rays is overexposed. Thus we cannot judge by these x-rays such important things as thickness of the soles and position of the coffin bone in relation to the ground. Hoof x-rays should always be made with a visible ground level on the shot. There’s also no clearly marked junction between the wall and the coronet on the x-rays, this prevents one from correctly judging the degree at which the bones have sunk down.

There’s no significant difference in size of spacing between the wall and the bone between the two hooves visible on the x-rays. What we do notice, actually, is a difference in the coffin bone positions inside the hoof capsules due to the difference in the hoof shapes (we can see this difference on the photos) — one hoof is more upright (has higher heels) and the other is flatter. And we can see the degree of the bone rotation in each hoof.

When a not ground parallel coffin bone in an x-ray is visible, this is a certain sign of overload of the lamellae suspension and therefore in the most of all cases the reason for the laminitis (Glenn Ramsey, PhD candidate, New Zealand's University of Auckland, "The effect of hoof angle variations on dorsal lamellar load in the equine hoof," Equine Veterinary Journal, September 2011).

Obtaining similar x-ray results, a veterinary professional has to inform the owner of the danger of further progress of the pathological changes in such hooves and on a possibility of the horse developing acute laminitis if it doesn't receive correct hoof care, which would help to bring the coffin bone to a physiologically correct position inside the hoof capsules, and, through this, to relieve the laminar corium thus preventing further damage to it.

* * *
We do encourage the horse owners to ask all the questions they might have on this article and also on any treatment of their horses by veterinarians. We recommend following steps:

— Do not be afraid to question anyone for the sake of your horse.
— If you have an expert, then this expert must be able to explain every detail you ask for and also all the coherence regarding present problem in the horse's body. Bear in mind that conventional veterinary care is not holistic care and your vet might not know about holistic care.
— Refuse the treatment suggested by a vet who recommends that you shut your horse in the box. Horses need free movement to be able to heal.
— Refuse the treatment suggested by a vet who recommends chemical painkillers, corticosteroids or antibiotics for your horse without warning on their harmful side effects and without looking into alternative therapy possibilities (herbal, homeopathic, etc.). Besides causing metabolical chaos in the horse's body that makes the healing process difficult, chemical drugs are well known for their severe side effects in the horse’s body. Just a few of the side-effects: non-steroidal anti-inflammatory pain killers are known as a cause of stomach and gut ulcers; antibiotics are known to suppress immunity; corticosteroids are listed as a common cause of laminitis in horses.
— Refuse the treatment by a vet who does not consider any psychological side of the horse behavior (horse is a herd animal, separation from the herd causes enormous stress and makes the healing difficult).
— Refuse treatment that only makes your horse “functioning” in order that you can use it again quickly.
— Search for the horse experts who will work at the body’s pace with the real healing processes the body has, no horse deserves less than this.

The cases presentation and analyse by Natalija Aleksandrova
English editing courtesy Tamlyn Labuschagne Ennor

Wednesday, July 10, 2013

Restricted grazing — does it bring the desired effect in horses?

By Natalija Aleksandrova

Continue the topic on importance of grass grazing for the horse, started here http://al-holistichorseandhoofcare.blogspot.com/2013/05/by-natalija-aleksandrova-through-course.html, we will look into a new research of Prof Paul D. Siciliano and his team published recently. The research brings more detailed proof to the fact that restricting a grazing time for a horse to fight her obesity and other metabolic problems, only creates more stress to the metabolism and overall health. When horse's grazing time is limited, she is able to consume more than 3 times more dry matter than normally. Such intensive load of nutrients in a short time stresses the digestive system and the whole metabolism.

Besides the physical stress to the body, it also brings mental stress to the horse. Such horse can never be in peace in a pasture, expecting her time there runs out each moment, and also, if the grazing area is limited to too small, expecting it will be empty of nutrients soon. Also, if the grazing area is limited, it brings additional mental stress to the horses as higher in hierarchy horses continuously chases away lower ones in search for more nutritional grazing spots.

The research

While researchers reported long ago weight lost helps improve horse’s overall health, until now no one hasn’t known exactly what impact restricted grazing has on the equine gastrointestinal health or nutrients intake. A group of North Carolina State University researches, led by Prof Paul D. Siciliano, set a goal to investigate in more detail if restricted pasture access affected horse’s intake rate, energy intake, and hindgut fermentation.

The team separated eight mature idle geldings into four groups and allowed each group pasture access for either 3, 6, 9, or 24 hours for seven days. After seven days, the team reassigned the groups to a different turnout treatment on an ungrazed pasture. By the end of the four-period study, each horse had been subjected to each pasture treatment. When not on pasture, the horses stayed in drylot pens with access to water and salt; horses in the three- and six-hour treatment groups had free-choice access to a low-quality grass hay. Throughout the study, the team recorded the amount of hay consumed and collected fecal samples from each horse on each Day 7.

The team also measured or estimated pasture plant composition, herbage mass (used to quantify pasture available to an animal), grazing height, and forage preference for each period. They noted no difference in digestible energy concentrations (DE) or initial herbage mass for each pasture. However, less pasture was available during periods 2 and 3 compared to 1 and 4.

Key study findings included:
— Horses' total daily dry matter (DM) intake (pasture plus hay, if hay was provided) was not affected by length of turnout time. In other words, horses consumed the same amount regardless of the amount of time they were allowed to graze.
— The team found the highest total daily DM intake — which equaled 1.4% of body weight (BW) — in horses on pasture for 24 hours, which is less than the 2-3% BW previous research suggested. Siciliano and colleagues suggested the lower DM intake in their study could be due to high temperatures seen during portions of the research: High temperatures have been shown to decrease forage intake in horses up to 15-20%.
— Pasture DM intake rate increased with restricted grazing. Horses grazing for only 3 hours had a higher intake rate compared to horses grazing for 9 and 24 hours, and horses grazing for 6 hours had a higher consumption rate than horses on pasture for 24 hours.

Amongst their other findings, the researchers also learned that horses' fecal pH — which is both influenced by diet and used as an indicator of hindgut pH — decreased as time on pasture decreased (lower pH means higher acidity); an acidic environment in the hindgut (termed hindgut acidosis) can lead to colic and other health concerns. This showed the team that length of time on pasture affected hindgut microbial fermentation. The authors believed the increase in rate of pasture intake could have played a role in the lower fecal pH, especially when the horses consumed high-quality pasture. However, they stressed, all fecal pH values were within the range considered to be normal.

Average DE intake was greatest when horses were on pasture for 24 hours, but total DE intake did not differ between treatments. The horses consumed 40%, 66%, 67%, and 94% of their total DE requirements with 3, 6, 9, and 24 hours of pasture access, respectively, which indicates that horses increase their rate of consumption with decreased time on pasture.

The team concluded that their findings support the belief that reduced time on pasture increases consumption rate and decreases fecal pH in horses.

“Simply reducing the time a horse spends at pasture may not always be an effective means of decreasing caloric intake,” said Siciliano. The team also noted that more work is needed to develop methods to accurately predict pasture intake of horses grazing for periods less than 24 hours.

The full study, "Effect of Restricted Pasture Access on Pasture Dry Matter Intake Rate, Dietary Energy Intake, and Fecal pH in Horses," is published in June in the Journal of Equine Veterinary Science.

***

If your pasture is specious enough to provide your horses with enough grazing throughout grazing seasons day and night, horses’ time in the pasture shouldn’t be limited artificially.

Also whenever it is possible, instead of closing your grazing area for recovering of grass there, when this area is limited, rather enough good quality hay should be provided for the horses additionally to grazing. This way the pasture will have a chance to recover naturally, at least to a certain extent, as the horses will choose naturally to eat more the higher quality hay, when the quality of the pasture grazing drops considerably due to overgrazing.

Horses, which are never limited in their grazing time have their life full and happy, finding a lot of other amusement in a pasture besides grazing.

For example, have a rest, including deep sleep:












Or play:








Communicate to each other:








Communicate to people:






Take care of the skin and coat:






Find a herbal help needed:






They move actively:






And, yes, they consume nutrients needed for life:









All photos except no. 12 by Berenika Bratny

Wednesday, June 5, 2013

The Importance of Species Appropriate Feeding and Eating Behaviour of Horses

by L.D.

Unlike the human’s digestive system, the horse's digestive system is designed by Nature to receive food in small portions almost constantly, day and night. By locking horses in stalls and making their feeding schedule similar to that of a humans — very few meals a day with long breaks in between — humans ruin the horse's organism, making the animal suffer from pain caused by the health disorders it develops as a consequence of the unnatural feeding schedule, such as gastric ulcers, colic, etc. In order for your horse to stay healthy and happy throughout its life, it should be provided species appropriate keeping conditions, which means conditions that are as close as possible to the natural way of life of the horse. This means all horses should be provided 24 hour access to grazing or/and hay, should be provided the possibility of unrestricted free movement 24 hours a day (the 'open stable' system) and be able to live together with equine companions. Now let’s take a scientific look into the importance of species appropriate feeding/eating behavior in horses.

__________________

This article focuses on the importance of species appropriate feeding/eating behaviour of equines. However, as also mentioned in the five freedoms (Farm Animal Welfare Council, 2009), which are building the base of the animal rights and protection, other factors are crucial in order to guarantee the well being of the horse:

1. Freedom from Hunger and Thirst — by ready access to fresh water and a diet to maintain full health and vigour.
2. Freedom from Discomfort — by providing an appropriate environment including shelter and a comfortable resting area.
3. Freedom from Pain, Injury or Disease — by prevention or rapid diagnosis and treatment.
4. Freedom to Express Normal Behaviour — by providing sufficient space, proper facilities and company of the animal's own kind.
5. Freedom from Fear and Distress — by ensuring conditions and treatment which avoid mental suffering.

Not only species appropriate feeding, but also being free to express species appropriate behaviour, such as herd-life, movement, mutual grooming and more, are of utmost importance and need to be fulfilled in order to guarantee the health and well being of the horses (and any other animal).

Scientifically speaking, equines are herbivore hind-gut fermentors. Having evolved to almost constantly eat little portions of long, rough fiber being low in energy. Observations and researches showed that horses being free to choose their feed stuff spend approximately 60% (~14 hours) of the day browsing and grazing (Gudmundsson and Dyrmundsson, 1994; McGreevy, 2004). Horses in a scarcer environment spend approximately 16–17 hours per day browsing and grazing, which may even exceed 19 hours in harsh seasons (McGreevy, 2004). However, the time spent eating strongly depends on several factors such as weather conditions, availability of feed stuff, gender, state of maturity and more. (Gudmundsson and Dyrmundsson, 1994).

Given the possibility to free range and express species appropriate eating behaviour the horse will consume approximatly 2–2,5% Dry Matter of their body weight within 24 hours, in the form of roughage. (National Research Council (U.S.), 1987; Kiley-Worthington, 1987; Dowler, et al., 2009; Wright, 1999).

Being able to free range and spend most of the day grazing results in approximately 57000 chewing movements (Cuddeford, 1999) on high fibre roughage (and about 40000 on roughage with an average fibre content, which in this research is the more likely number to work with) (Frape, 2004). Figures as such are often critically questioned as they are mainly derived from researches and observations from wild, feral or semi feral equines, however the genetic make up of ingestive related behaviour/instincts and physiology of the digestive tract have remained relatively unchanged over the last 6000 years of domestication and breeding (Koene and Gremmen, 2002; Dierendonck, 2006), which is then directly linked to the high occurrence of health and behaviour problems due to inappropriate nutrition.

The same eating behaviour performed by free ranging horses can be seen in domestic horses when given the possibility to execute this normal and instinctive behaviour (Kiley-Worthington, 1987). However, most domestic horses, nowadays, are only able to express limited normal eating behaviour due to human management. For example concentrates in the form of pellets, muesli or oats are fed in restricted meals with or without limited amounts of pre-cut hay or haylage. This change of feedstuff also manifests a change of eating behaviour in terms of eating time, chewing movements and, importantly, saliva production.

A horse being free to graze adequate mature pasture, 24/7, will consume an approximate Dry Matter intake of grass of 2 Kg per 100 Kg body weight per day (600 Kg horse). When being limited in grazing the horse will consume approximately 0,8 Kg DM of grass in one hour. The horse given limited hay at specific feed times will spend approximately 40 minutes per 1 Kg of hay, resulting in about 1,2 Kg Dry Matter intake per hour (Ellis, 2004). When given hay ad libitum it is most likely that the horse will spend longer eating the 1 ncentrates differs considerably; as the horse will only spend approximately 10 minutes eating 1 kg of concentrates (Ellis, 2004). This means that the horse has a high energy intake in a very short time. Which, firstly, the digestive system was not evolved for and secondly, the horse will spend much less time eating and chewing. This might result in a higher risk and occurrence of undesirable stereotypic behaviour and other health problems (Davidson and Harris, 2000) and might therefore influence the short and long term performance of the horse.

The horse's teeth have evolved for heavy wearing exposure and thus would need similar conditions in order to wear at normal rates (Baker and Easley, 1951). It has been observed that the change of the angle of the incisors, commonly in domestic horses is something which does not occur to such an extent in feral or wild horses. This means that abnormal wear takes place in many of the domestic horses. Such misalignments can have severe consequences on digestion and the whole equine body. As the tempro-mandibular joint becomes further misaligned it exerts a crucial role in altering the biomechanics of the whole body. Besides that, a change in the angle of the incisors means that the surface to surface contact of the molars is also put in an abnormal state forcing the horse to clinch its jaw in order to be able to chew feedstuff properly (LaFlure, 2001). Reasons for that abnormal wear are firstly, that the horse is fed with too little high fibre roughage. Secondly, it does not need to bite correctly anymore (reduced usage of the incisors), because the roughage is most likely precut. And, thirdly, the horse gets too much concentrated energy on which it needs to chew at least four time less than on hay (approximately 3000 chewing movements on 1 kg hay and 750 on 1 kg concentrates) (Frape, 1998).



As the production of salvia is linked to chewing (Alexander and Hickson, 1970) direct relations can and must be drawn. While eating a minimum of 14 hours a day and an amount of approximately 2–2.5% Dry Matter of the body weight, the horse produces approximately 4,5 litres of saliva per one Kilogram Dry Matter roughage, resulting in approximately 40–60 liters of saliva per day (Harris, 1999; McGreevy, 2004). Producing sufficient salvia is crucial for the buffering effect of stomach acidity. Saliva, with its high bicarbonate content, has an alkaline level and thus is able to balance the acid level in the stomach (Picavet, 2002). If insufficient saliva is produced at constant rates spread over the whole day, the buffering effects of the alkaline bicarbonate are diminished; the gastric acidity rises and risk of gastric ulceration increases considerably (Pagan, 1997). It has been observed that the occurrence of gastric ulceration happens most commonly in the upper region of the horse's stomach, as this part of the stomach does not contain a mucous membrane layer and neither produces alkaline bicarbonate as an acid neutralizer. The only protection that the upper region of the stomach has from gastric acid is the bicarbonate coming from sufficient saliva production and the natural buffering capacity of roughage (Pagan, 2008). Being exposed to a higher acidic level for more than three to four hours decreases tissue resistance dramatically, and the first signs of damage become visible after ten to twelve hours (Steward, 2003). Studies show that approximately 60% of performance horses and approximately 37% of leisure horses show gastric ulceration (Picavet, 2002). The highest occurrence of gastric ulceration is found in race horses. More than 90% of all race horses show gastric ulcerations to various degrees (Pagan, 2008). It has been indicated that horses would not voluntary starve themselves for more than four hours (Krazak, et al., 1991) as acid levels in the stomach increase by then; causing discomfort and initiating the desire to chew and graze, which effectively supplies buffering alkaline bicarbonate to the affected over acidic area.

Having evolved as a constant browser grazer also means that constant movement of the digestive tract is present and necessary to keep the micro environment healthy and active. The presence of beneficial bacteria prevents the spreading of other, potentially pathogenic bacteria (Pagan, 2008). If this constant peristaltic movement is not assured, the risk of colic (abdominal pain) increases considerably. In order to guarantee this peristaltic movement, the stabled horse being restricted in roughage intake will often be observed occupying itself with eating it's bedding, because it lacks fibre, saliva production as well as it needs to occupy it's time. Eating bedding is certainly beneficial for chewing, saliva production and time occupation and thus helpful in decreasing the risk of gastric ulceration, but straw bedding should not be the major source of roughage (it has almost no nutritional value and contains larger amounts of lignin, which is more difficult to digest.) However and importantly, excessive consumption of wheat straw bedding, has been implicated in the development of impaction colic (Thorne, et al., 2005; Cohen, et al., 1999).

Applying sub-optimal feeding regimes, not guaranteeing the natural requirements of almost constant eating, chewing, producing saliva and having a "full" digestive tract, does have severe consequences on physical and mental health. The development of gastric ulceration, colic, but also the development of abnormal behaviours, such as crib biting, (e.g. Kiley-Worthington, 1987; McGreevy, et al., 1995) might result and with that have a direct influence on the horses welfare, well-being and thus on the five freedoms (Waran, 2007).

English Edit Courtesy of Tamlyn Labuschagne Ennor 2012

Wednesday, May 1, 2013

Grass grazing — essential for the horse

by Natalija Aleksandrova

Through the course of its evolution, the horse digestive system changed to one best suitable for digesting grass. It gave to the modern horse means by which it can extract energy needed for life from all forms of the grass nature offers through the seasons. For this the horse got necessary gut flora and fauna, and its caecum considerably expanded. Being still quite primitive and much less efficient than in ruminants, equid's digestive system, combined with high rates of voluntary food intake, gave a great advantage to horses comparing to ruminants in feeding on coarse grasslands, characterized by high fiber and low protein content.

If the horse is provided with all other essential needs, when provided with unlimited access to grazing the whole year-round and unrestricted movement day and night, its body is able to utilize grass in the most beneficial way during each season. Spring grasses give a boost to horses during their mating season, helps them to gain weight and energy back coming out of winter, to fill for a lack of nutrients after the winter season, as well as provides extra energy to foals which is needed for their proper growth and development. Fat deposits are stored in horses' bodies during summer and autumn grazing, which is then used during the winter.

When the horse is allowed its natural grazing habits the whole year-round, it is never abruptly exposed to a new type of food, what could affect negatively its metabolism. Spring pastures have a mix of both new growth green plants and the previous year's dried ones, so the animal goes through a gradual transition to the food that is richer in nutrients. As new grass stops growing in autumn, the horse gradually converts to eating more fibrous dried plants, which has its benefits in the horses body during the colder weather. Also, despite popular believes, dry winter grasses still may be high in sugars and other nutrients, they are not the same as straw, which is a byproduct of agricultural business.

The fermentation process of insoluble plant fibers in the hind gut creates heat in the horse body. Dried mature grasses and the branches of bushes and trees have higher insoluble fiber contents than that of fresh green plants. It is more natural for the horse to eat green grass in the summer, when it is hot, because less heat is produced during fermentation of the soluble fibers the grass contains, and thus the animal doesn't have to struggle to rid his body of excess internal heat. It is beneficial for the horse to eat dry plants that are rich in the insoluble fiber in cold weather. The fiber is digested slowly and the heat is sustained for a longer time in the body, helping the animal to stay warm during the winter.

Restricting an access to grazing through reducing a time a horse spends in a pasture, may bring only a bigger mess to the horse's metabolism, and thus only opposite to the 'thinning' or 'laminitis preventing' effects. Studies showed that, when a horse knows that her time in a pasture will be limited, she is able to consume up to 3 times bigger amount of grass in a given time as normally (P.D.Siciliano). It means, if a horse is let to the pasture for 4 hours, she is able to consume an amount of grass which normally she would eat in 12 hours, in other words, approximately a half of her normal day/night amount.

In general, it is very incorrect to say 'grass is bad for the horse', because grass has been the most natural food for the horse ever since it evolved into a free-ranging, primarily grazing, plains dweller. We need to learn and consider all the effects that humans cause when manipulating the horses' lifestyle and their pastures in order to prevent situations where grass turns into a 'danger'. Such as, limiting a horses' access to food, changing the chemistry inside the horse's stomach which makes it unable to properly absorb all the nutrients from the grasses, providing horses with over-fertilized mono-species pastures manipulated especially to suit cattle who have a very different metabolism, or restricting horses in the free movement which damages their metabolism, etc.

Domestic horses kept naturally. Grazing in a natural not fertilized pasture. Beginning of spring. Latvia:




The same horses later in the spring, a few days in between these two shots:





Domestic horses kept naturally. Spring grazing in not fertilized pasture. Poland:








Przewaski wild horses in Ukraine. Summer grazing:








Konik Polski wild horses. Latvia and Poland. Summer grazing:







Domestic horses kept naturally. Summer grazing in a natural not fertilized pasture. Latvia:












Domestic horses kept naturally. Summer grazing in a natural not fertilized pasture. Norway:




Konik Polski wild horses grazing in autumn. Poland:







Domestic horses kept naturally. Winter grazing in a natural not fertilized pasture. Poland:





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Photos © author, B. Bratny, Z. Wroblewsky