Sam Murphy has been involved in the equine industry for 35 years. Sam has worked with some of racing’s greats - Jim Bolger, John Oxx and Paddy Prendergast to name but a few - before setting up his own business in equine transportation.

Recently Sam has delved into a new area of business designing lights to be used in stables, but these are not just any kind of lights, as you will find out throughout the course of this article. Sam’s new product design stemmed from the knowledge that equine light therapy can successfully alter a horse’s circadian rhythm and therefore has a certain effect on hormone production. This knowledge formed the basis for designing his new product.

THE SEASONS

The horse has a season in which to thrive, prosper and breed (spring) and a season in which he needs to preserve himself to survive (winter). The horse in captivity has available nutrition but his system is still telling him it is winter and that he needs to conserve energy and try to store reserves.

Sam explains that “By extending day length we can fool the horse into thinking he is in a different season. The horse will then alter how he converts his feed. Trials have been carried out recently to analyse the effect of extended photoperiod in horses, and results have shown that, in the male, light has been proven to enhance testosterone and therefore increase muscle mass (Nambo et al, 2010). We create a new circadian rhythm by controlling the length of day versus night.”

Following intensive research and trials over the past three years along with the help and guidance of Dr Domingo Tortonese of Bristol University, Dr Barbara Murphy founder of Equilume and racehorse trainers Mark Johnston and Mick Halford, Sam has designed a system that will create a continuous uninterrupted day followed by a continuous uninterrupted night. In this way the duration and effect of the hormones serotonin and melatonin can be controlled. Please see Table 1 below.

FACTS ABOUT LIGHT AND HORMONES

  • Full-spectrum light is light that covers all wavelengths that are useful to plant or animal life - in particular, sunlight is considered full spectrum light. See Figure 1 left.
  • Lux is a measure of the intensity of light that hits or passes through a surface, as perceived by the human eye.
  • Light manipulation is already widely used within the equine breeding industry to advance oestrus cycling in mares.
  • This allows mares to be covered very early in the year, before the stage at which most mares would be cycling naturally.
  • The optimum light signal required to inhibit melatonin in the horse has now been identified (Walsh et al, 2012. The Veterinary Journal).
  • Full spectrum sunlight is very important in the hormonal recognition of light.
  • The length of day versus night is the most important cue for allowing animals to determine which season it is and therefore has effects on the reproductive system, coat quality, growth and many other things.

    • THE PRODUCT

    Sam Murphy has designed a product that emanates full spectrum (daylight-mimicking) light incorporating the correct amount of blue light required to inhibit melatonin in the horse, as has been identified by Dr Murphy’s team at UCD. The system has a special 365-day timer that allows the length of light provided to the horses to be slightly altered every day.

    The result is that the horse will receive nine months of long days and three months of short days. The spring is advanced by 45 days and autumn extended by 45 days resulting in the horse experiencing a very short winter.

    Basically the system, once set, will run automatically for 365 days and alter the seasons.

    Key points

  • The lighting system is to be installed in horse stables.
  • The lights are fitted with a light monitor. The monitor calculates the level of natural light within each individual stable. If your stable is provided with 150 lux naturally then the lighting system will only provide 150 lux. As the light changes throughout the day the system will alter the amount of light provided to ensure your horse receives the full amount of daylight needed for peak serotonin.
  • The light consumes 50w on full power but with the sensor it can run as low as 5w-10w throughout the day. The average running cost is around 8c-10c per day.
  • The system is also integrated with a low level red light security system. During the time the horses are to be in darkness, this low level red light comes on. This allows for yard managers to see and work with the horses at all times.
  • The level of red light provided does not disturb the natural production of melatonin.
  • Increased levels of light are also linked to lower bacterial and fungal counts from within the environment. This may be an additional positive effect of the implementation of increased light levels, as the highest prevalence of fungal or bacterial skin and respiratory infections are within the winter.
  • Therefore increasing light levels and decreasing bacterial and fungal levels may be of benefit to the horses’ well-being.

    • For further details contact:

    Sam Murphy

    Tel: 086 4177807