Cushing Candidate?

As my followers (and detractors) will undoubtedly confirm, I am often dismissive of traces of blood in the white line. Such traces are often the result of a trauma at some indeterminate time in the past and now, often between three and eight months later, neither owner, nor horse, nor hoof have any recollection of anything untoward and at the next trim, the traces will probably have disappeared all by themselves.

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(trim incomplete)

Certainly, none of the photos I have ever commented upon, would have given us at Sabots Libres any cause for concern. The traces were small, often relatively vague, and frequently only reported in one foot. But the case I am about to touch on here is definitely a cause for concern and set the alarm bells ringing during a routine 6 weekly trim yesterday.

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The horse in question is a 22 year old mare, shod on the recommendation of the breeder/seller until aged about 20 due to a trauma, resulting in club feet, suffered when young. (This is not a classic case of club foot as described elsewhere on this site but could have been avoided by the same means – however, that is beyond the scope of this article).

More significant is that she was being fed grain and cereal up to the age of about 18. This was stopped due to allergic reactions to cereals and pollen–the latter probably being exacerbated by the inappropriate feed. This cessation of feeding supplements and an altered system of distribution of (ad lib) hay was successful in reducing the allergies to an insignificant level.

But the damage had probably already been long done. The last trim showed traces of red in the white line that do set off alarm bells. As we can see from this first photograph, there are red traces extending from the rear into the front quarters.

The extent of the traces is the main cause for concern; they are particularly concentrated around both sides whereas ‘insignificant’ traumatic damage will usually be seen at the front and medially.

When we examine the other hoof, it is clear that something is not right. In this case, the red traces are visible almost full circle. Clearly something out of the ordinary has been going on in the hoof which cannot be written off as a couple of unhandy manoeuvres in the field.

What is also obvious, is that this is not an ‘ordinary’ laminitis. The horse no longer has access to grains nor cereals, the grass is far from rich in sugars and essentially, there has been–and still is–no sign of discomfort in the hoofs. What is noticeable/notable is the poor moult whereby there is still a lot of thicker hair in patches. This gives rise to immediate thoughts of Cushing or, more correctly, PPID (Pituitary Pars Intermedia Dysfunction). This is an incurable but reasonably treatable hormonal condition whereby the body loses its ability to control certain functions. This can manifest itself in various symptoms, among which a poor moult, excessive disordered hair-growth and chronic laminitis.

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The area top-right is the normal summer coat while bottom-left the coat is clearly a lot thicker

When we add up these factors–a long-term grain diet (which additionally has led to allergic reactions), the poor moult and unusually large traces of blood in the white line–then our suspicions are aroused significantly. Obviously, it is not possible to simply say ‘Cushings’, the need for proper testing is unavoidable. However, this is not the best moment to test. The period of greatest–and most testable–hormonal activity is from August to October with the peak in September; by November, the values have usually receded to insignificant and thus indeterminate levels. For this reason, a blood sample will be taken in a few weeks time and sent off for testing.

The results will be posted here in due course.

When are “Good Feet” really “Bad Feet”?

In my line of work, it is nigh on impossible to avoid visiting a stable or livery yard every now and again. And although I am almost always visiting to tend my unshod horse-clients, I cannot help but notice just one or two of the stablemates; in particular, their feet!

Unfortunately, it is tactically unethical to take photos of these hoofs, therefore I have restricted the images to one basic photo with annotation – hopefully just this one hoof will be clear enough!

Shod hoof

Fig. 1 The hoof without annotation

 

In this first photograph fig. 1, try to discern the actual outline of this hoof – the photograph is has been taken almost at right angles to the hoof.  Don’t cheat by scrolling down to look at the next image 🙂

 

 

 

 

 

 

 

 

 

 

 

 

Shod hoof - perceived heel height

Fig. 2 This is the perceived heel height – compare it with the next photo

 

So, here in fig. 2 we see the same hoof but now I have added a little annotation to help you. We can now clearly see an outline around the visible hoof and, as the orange lines show, this looks like a hoof with the oft prescribed low heels.

At a recent conformation clinic, this type of hoof was described to me as being one with low heels since you can see the distance between the coronary band at the back and the ground is quite small.

 

 

 

 

 

Shod hoof - actual heel height

Fig. 3 Here the actual height of the heels is demonstrated

 

OK. Same hoof, but here in fig. 3 a different annotation; this is the actual outline of the hoof. Compare it with the perceived outline in fig. 2 above and have another look at fig. 1 the original photo to see just what we have annotated here.

In this annotation it is very clear that the actual contact point of the heel is much further forward than the perceived point shown above. The apparent height of the heel seems little changed but if we look at the actual height indicated by the orange lines, then we see that the heels are in fact high.

 

 

 

 

 

Shod hoof - desired form

Fig. 4 The form the hoof should have

 

In fig. 4 we see the low heels again – but no longer on a perceived level but rather on the more ideal line of the hoof; the toe is now much shorter and although it may not become quite as flat as it appears here, the coronet should also flatten out a little if the shoes are removed.

So, just what is wrong with the heels in these photos? After all, a farrier has shod them and has obviously felt they were good enough.

 

Essentially, the whole weight-bearing structure of the foot has been moved forwards by – in this case – roughly 15 millimetres. If we consider the point at which the hoof is hinged with the rest of the leg, we see firstly that the weight is being carried further back than is intended and, secondly, that the length of the hoof at the toe creates a longer roll moment increasing effort – and stress – with every step.

 

 

Hoof - weight-bearing and rollover points

Fig. 5 The weight-bearing line and the rollover moments of the unshod (green) and shod (red) hoof

 

Here in fig. 5, the blue line () shows the centre of the weight-bearing axis and we can clearly see the extra length in the moment of the shod hoof (x) compared with that of the unshod hoof (). This extra moment costs energy and effort; although not exactly the same, you can experience the difference by lifting the end of a pole one metre long and lifting the end of one 1½ metres long. The lengths used in the analogy are not synonymous with that of the hoof but remember, the horse is rolling ±150kg over its front hoofs – with every step!

If you are wondering why the green line does not reach front of the hoof wall, the answer is simple – when the hoof is correctly trimmed (or even allowed to wear naturally), the edge of the hoof is rounded bringing the rollover point back from edge of the front wall.

If we look further at the hoof, we see yet more evidence of farrier-damage. There are holes all around the outside wall from previous shoeing and these are allied to a crumbling lower edge. It is often – quite incorrectly – said that a horse needs shoeing because it has brittle hoofs. The real case is that a horse has brittle hoofs because it is shod. No amount of care, attention and biotin is going to protect a hoof from degrading if someone has hammered nails into it. This fact is frequently overlooked or even blatantly denied by proponents of shoeing; but how is it possible that when a hoof has been given a chance to develop in a nature conscious way, that this sort of damage is never evident, compared with presence in the majority of shod horses.

Very frequently a clear bulbous coronet is visible – this is often masked in two-dimensional photographs by the hair around the coronet, as is the case here. This bulbous form is caused essentially by the incorrect distribution of weight in the periphery of the hoof. By overloading the hoof wall, the coronet is pushed upwards and distorted – sometimes very severely.

V behind hoof

Fig. 6 A V-shape below the heel bulbs caused by forces from the horse shoes.

Flatter form of unshod hoof

Fig. 7 Much flatter form of the unshod hoof (this horse has never been shod)

 

We can also see a V shape under the heel bulbs caused by this same abnormal pressure. Compare the photographs left and right: the horse in fig. 6 has a clear V shape whereas the horse in fig. 7 the V is much flatter – almost to the point of being non-existent. The horse in fig. 7 is 8 years old and has never been shod; the horse in the other photographs is 10 years old and has been shod since before he was bought by his present owners when he was just 3 years old.

 

 

 

 

 

 

It is very important to note here that “bad feet” are NOT a result of breed, lineage or other genetic factors – although this can very occasionally play some role – but rather the effects of shoeing allied to being kept in a box or stable and in almost all cases exacerbated by bad feeding practices. Stabling a horse restricts its movement – a horse should be able to cover 12 – 18km per day – and forces it to stand for hours on end in its own excreta which seeps between the shoe and the hoof creating an ideal, airless environment for destructive bacteria to survive. Most (stabled) horses are fed two or three times a day, a mixture of grains and cereals – products ideal for mice and birds but certainly not for the digestive system of the horse – and only have limited access to raw hay/grass and other herbs which form 100% of the dietary requirement. This access to raw foodstuffs should be unrestricted since a horse grazes for a major part of the day – taking between 12 and 16 “meals” in every 24 hours. The horse moves to eat and eats to move – remove this elementary factor and the horse is put straight into an unhealthy situation.

Keeping Warm Feet

Horses are, like humans and all other mammals, warm blooded (including the so-called cold-blood breeds). This means that the body’s temperature is regulated internally and not by external influences (the sun).

A direct result of this is the minimal variation in temperature noted over the whole body. Some areas are slightly warmer because of the greater number of blood vessels running close to the surface of the skin; others are slightly cooler because of natural physiological reaction to the cold and the automatic attempt to maintain the core temperature.

The maximum variation in temperature within the body should be no more than about 2°C (on the surface this can be slightly more). This makes the following picture quite alarming:

One shod hoofWe can see a very clear large decrease in temperature in the front right hoof and leg. Clearly the front of the legs is cooler than the rear (where the blood vessels run) and the muscular areas are much warmer; however, we see that the temperature of the hoofs is very close to the temperature of the leg muscles. It is then horrific to note that from the knee downwards the leg with the shod hoof is considerably colder: as cold as the extreme surface of the other legs but then right through to the core.

This is as a result of the closing off of the blood vessels running through the underside of the navicular bone. Raising up the heels – as a result of standard shoeing practices – emulates the part of the pump system that along with the hoof mechanism insures efficient circulation through hoofs and legs. The pump mechanism works by partially closing off the blood vessels and allowing a build-up of pressure; as soon as the vessels are fully opened, the pressure is released by pumping blood through. The problem is that there is no release from this partial emulation; the result is cold legs.

Blood vessels in the hoofWe can see in this next photograph just how concentrated the blood vessels in the hoof are; this means that, by definition, the hoofs should be warm – as shown in the three unshod hoofs in the thermograph above.

These pictures alone should be clear enough evidence that shoeing horses is not only unnecessary but also undesirable and even damaging. I would even go as far as to advocate that it is a form of cruelty since the horse is actually being abused.

 

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