DISEASE AWAR STABLING,
LIGHT UP THEIR LIFE LIKE US, HORSES CAN GET ‘THE BLUES’ AS THE NIGHTS DRAW IN. HORSELIGHT EXPLAINS HOW SUPPLEMENTARY
T
LIGHTING CAN HELP.
he horse’s body prefers the summer months. They naturally put and keep on body condition, their coat and skin improve and they have the high amounts of Vitamin D required to help the body’s internal processes. It’s also the most natural time for foaling. The advantages of light therapy for the performance horse include reduced coat shedding, improved food conversion, faster recovery rates and anecdotal reports of happier horses. It is widely recognised t at any u ans su er it SAD during the short winter days, and owners indicate that their horses seem to be much happier and alert when stabled under HorseLight.
CIRCADIAN RHYTHM In the northern hemisphere the daylight hours vary greatly between the summer months and the winter. In December we have eight hours of daylight and 16 hours of darkness. March to September there is equal day and night (Equinox). June has the longest day (Summer Solstice).
By providing daylight-strength arti cial lig t in t e stable e can strengthen the circadian rhythm which has many positive ealt bene ts for t e orse Research over the last decade as identi ed t at s eci c lig t can a ect and regulate t e circadian rhythm. Strong blue lig t s itc es o t e roduction of melatonin (the sleep hormone) and the daytime decrease of melatonin results in a more active horse. The increased activity and improved feed intake improves body condition and accounts for any ot er bene ts Blue light within the shortwavelength blue light spectrum n is t e ost e ecti e at inhibiting melatonin secretion, as production of its precursor, melanopsin, is particularly sensitive to it. Normal white LED or fluorescent lig ts do not deli er blue light at the strength required to a e any real e ect on melatonin secretion.
COAT CONDITION The relationship between coat shedding, day length and light intensity has been documented in several studies. One of the
earlier ones was A&M University in Texas in the 1980s where they compared extended versus traditional day lengths for controlling coat lengths. In this study 16 yearlings and two year-old mares and geldings were randomly assigned to natural day length or extended day length groups, the latter group receiving 16 hours of daylight per day. The study found that the coats of those horses exposed to extended daylight did not grow nearly as fast as those receiving normal daylight. We know that the coat maintenance is best achieved when light therapy is combined with using rugs to compensate for the winter coat. Light therapy should begin before mid-July to maintain the summer coat into autumn. Similarly, eight weeks of light therapy is required to initiate shedding the coat earlier in the spring.
six horses were maintained for consecutive 48 hour periods under a Light: Red (LR) and a Light: Dark (LD) photo-schedule. Transitions from light (>200 lux, polychromatic white light) to red (5 lux, peak wavelength 625nm) or dark (<0.5 lux), and vice versa, coincided with ambient sunset and sunrise times. Low intensity red light at night did not impact the pattern of melatonin secretion in this study and is, therefore, unlikely to impact the physiology of circadian or seasonal regulation. A red light is useful for allo ing su cient obser ational light at night such as for foaling or not disturbing other horses when arriving home late from competition. Changing from white light to red observational lig t at nig t as a cal ing e ect on a yard as horses appear to be ‘more asleep’.
RED LIGHT AT NIGHT
BELOW: EN VOGUE AND GROOM LUCY SCUDAMORE WITH HORSELIGHT.
Switching to red light at night further strengthens the circadian rhythm. Red light has no e ect on elatonin secretion and therefore allows full melatonin release at night which encourages recovery and deep sleep. This is useful to allow for human interaction with horses without ‘waking them up’ which can occur at late-night checks. Studies have shown that dim red light does not suppress the nightly rise in serum melatonin levels in horses. In one study,
