So many factors affect the way the hoof grows that it can be difficult to
unravel the mystery.
A recent study into hoof growth has approached the subject from several
directions: equine medicine, maths, physics and stem cell biology have all
played a part.
The findings have revealed a clearer understanding of how equine hooves
grow and how abnormal hoof shapes may develop.
The study entitled ‘Physics of animal health: On the mechanobiology of
hoof growth and form’ was conducted by the School of Veterinary Medicine and
Science at the University of Nottingham in collaboration with the WALTHAM
Centre for Pet Nutrition and the Royal Veterinary College. A full report is
published in the Royal Society Interface Journal.
Lead author Dr Cyril Rauch, of the School of Veterinary Medicine and
Science, University of Nottingham, said: “With new scientific inputs from
physics, mathematics and biology, this study provides an entirely new paradigm
regarding hard growing tissues such as the horse hoof, which can be applied
across cattle, sheep and other species, to unify a set of apparently disparate
conditions and clarify the roles of physics and/or biology.”
Nicola Menzies-Gow, of the Royal Veterinary College, said: “We believe
that this novel approach has the potential to provide alternative directions to
follow with respect to understanding chronic hoof pathologies.”
Laboratory -based studies looked at how the synthesis of the hoof
capsule starts from the coronet with the soft papillae undergoing gradual
transition through three interpapillary regions into hard keratinised tissue.
Mathematics, physics and cell biology were then used to explain and
describe how the dorsal hoof wall can grow in a curved manner rather than the
usual straight manner as a result of faster growth from the coronary band at
the quarters compared to the toe region.
A field study looked at one hundred and twenty-nine horses. All were at
least 5 years old and under 144 cm (less than 14.2hh) high with shoes. They
were healthy at the time of evaluation and none had a history of laminitis/hoof
conditions, or pre-existing health conditions; neither had they been treated
for pituitary pars intermedia dysfunction (PPID - Equine Cushing’s disease).
The research team recorded horse weight and Body Condition Score, hoof
width and they measured the curvature of the dorsal wall from standardised
photographs. This allowed the influence of body weight on the balances of the
stresses affecting hoof growth to be evaluated. The results suggest that being
proportionally heavier may promote straighter hoof growth and that being too
lean may precipitate poor hoof growth and the development of a hoof with a
dorsal curved shape.
The study also showed that a high concentration of insulin stimulated
equine progenitor keratinocytes (the cells responsible for producing the hoof
wall) to grow in culture. The researchers suggest that if this happens over
time in the live animal, it is possible that it could affect the growth
stresses within the hoof and so promote a dorsal curved hoof shape.
“These results taken together can explain how the hoof grows and how it
is possible for it to develop a dorsal curvature,” said Dr Menzies-Gow.
“However, it should be acknowledged that this does not take into account the
genetic or metabolic influences on hoof growth nor the role of hoof trimming
and shoeing in maintaining a mechanically healthy hoof. It is appreciated that
the underlying biology of hoof growth remains an essential factor for hoof
pathologies.”
Dr Cyril Rauch continued: “Given that the hoof is a weight bearing
element it is essential to untangle the biology from the physics in this
system; only then can meaningful biological and/or physical causes be
prescribed for particular hoof shape. Removing the cause(s) when physically or
biologically possible is essential to resolve hoof conditions.”
For more details, see:
R Al-Agele; E Paul; S Taylor; C Watson; C
Sturrock; M Drakopoulos; R C Atwood; C S Rutland; NJ Menzies-Gow; E Knowles; J
Elliott; P Harris; C Rauch. (2019) Physics of animal health: On the
mechanobiology of hoof growth and form.
Journal of the Royal Society Interface, (2019)
Vol 16 Issue 155
1 comment:
Laminae from the toe also grow horizontally and not only from the coronary band. Since farriers now seem to rasp the toe wall all over I’ve found this to weaken the toe and hence the quarters grow faster resulting in the curve of the toe wall. There was a time when if the rasp nicked above the nail holes it was deemed to be a bad mistake.
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