Sunday, July 28, 2019

Owners’ opinions of equine calming products

 Equine calming products (ECPs) are often used by owners to calm challenging or “unruly” horses, often with little scientific basis for their action and with little understanding of how, why or, indeed, whether they actually work.

Diane Ross of the North Highland College, University of Highlands and Islands, Scotland, and Jayne Roberts of Equijay, Brisbane, Australia, conducted a study to investigate owners’ attitudes to such products.

They distributed a survey to horse owners in the north of Scotland                                      .

How did respondents think ECPs work? Opinions varied. Over half (59%) of those replying thought magnesium was responsible for the calming effect; 9% thought it was due to herbs, valerian or tryptophan and 32% did not know which of the ingredients were responsible.

Were owners' satisfied that ECPs had the desired effect? A positive calming effect was reported by 48% of respondents; 30% were uncertain; 25% thought there was no effect; and 5% thought that rather than calming the horse they made their behaviour worse.

The authors conclude that horse owners appear willing to use ECPs without underpinning knowledge of ingredients or scientific evidence that they work.

For more details, see:

Equine Calming Products: A short survey into their use, effect, and knowledge using a small sample of horse owners in the north of Scotland, UK.
Ross DJ, Roberts JL.
J Equine Vet Sci. (2018) 68:63-67.

Fresh insight into hoof growth

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

Saturday, July 27, 2019

Face flies strangles risk
Good biosecurity is vital for limiting the spread of contagious diseases like strangles. Caused by Streptococcus equi subspecies equi (S. equi), strangles spreads readily from horse to horse and by indirect transmission on items such as clothes, tack, and buckets.

Stopping an outbreak requires affected horses to be isolated to prevent spread to
susceptible animals. Measures are also needed to prevent indirect transmission, such as using
separate equipment and clothing for handling affected and unaffected horses, and disinfecting anything that comes in contact with an infected animal.

One possible source of indirect transmission, which may prove more difficult to do anything about, was highlighted by recent research.

Dr Nic Pusterla, professor in the Department of Medicine and Epidemiology, at the School of Veterinary Medicine, University of California, Davis, was lead author of a short communication published in the journal Medical and Veterinary Entomology.

The study set out to see if S. equi could be found in face flies on a farm with a confirmed outbreak of strangles.

The researchers collected 1856 face flies (Musca autumnalis) using conventional fly traps. The flies were tested using quantitative polymerase chain reaction (qPCR), looking for evidence of S equi. Of the total flies caught, ten (=0.54%) tested qPCR positive for S. equi.

The authors conclude: “The results may implicate the presence of face flies as a risk factor for the transmission of S. equi and highlight the need to institute proper husbandry measures, biosecurity protocols and fly control in order to reduce the potential for infection in at-risk horses.”

For more details:

Molecular detection of Streptococcus equi subspecies equi in face flies (Musca autumnalis) collected during a strangles outbreak on a Thoroughbred farm.
Pusterla N, Bowers J, Barnum S, Hall JA.
Med Vet Entomol. (2019)