Breeding management of the mare can involve techniques that begin as soon as early winter to prepare for a successful breeding season the next spring. One such technique is the use of artificial lighting. This technique can successfully coax the mare’s body into thinking that the breeding season is here earlier in the season.
Mares are seasonally polyestrous and during the winter months they enter a reproductive quiescence called anestrus, where they are not normally reproductively active. Since the nature of the performance and racehorse industry favors a foal born as early in the year as possible, manipulating the mare to begin the estrous period, or cycling, earlier in the year can be advantageous.
Control of the mare’s reproductive circadian rhythm comes from the photoperiod. The retina of the eye perceives the daylight and that information is conveyed to the brain via a complex nervous pathway to govern reproduction. The natural events that regulate the mare’s physiological response to photoperiod actually have more to do with the length of dark hours than the length of light hours.
Melatonin, a hormone that suppresses reproductive activity, is produced during the dark hours. During the winter, the dark hours increase and therefore the mare’s reproductive activity decreases. Managing the amount of dark hours the mare perceives gives breeding managers the opportunity to dictate when she will be reproductively active and can be bred.
Check out Equilume to explore options for artificial lighting in different housing environments
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