How to Keep Your Pregnant Mare Comfortable Amidst Seasonal and Lighting Changes

Those who are familiar with horses sometimes describe mares as being polyestrous explains owner Richard D. Schibell.  These animals often go through several heat cycles each year.  However, the reproductive tracts of mares rarely cycle in the autumn and winter.  The body chemistry of mares instinctually determines it is a bad idea to enter such a state.  The mare’s temperature naturally decreases as the days shorten in the fall and winter months.  Mares need about 16 hours of daylight along with eight hours of darkness to continue their reproductive functionality.  Provide your mare with the proper environment and you will have done your part to prevent a premature estrous.

Supplemental Lighting for Mares

In some situations, it makes sense to use supplemental lighting for a mare.  Though using artificial lighting is not a new technique, it is worth mentioning as it is quite effective.  Lighting really will kick-start the mare’s cycle through manipulating her body into believing the winter months are ending and the spring is right around the corner.  The mare’s retina registers the supplemental light, communicating to the body that it should suppress the production of melatonin, spurring an impact on several hormones and causing the follicle to be stimulated and subsequently developed. The use of artificial light to stimulate the mare’s cycle is especially helpful in preserving time if you seek an early foal.  This strategy is also effective in response to pre-breeding.

If you decide to use supplemental lighting for your mare, be sure to apply it as early as possible within reason.  The mare should be beneath the light starting in the final weeks of November or the first couple weeks of December.  This timing provides the mare with between a month and three months of photo-stimulation that triggers the start of the initial estrous cycle.  Just be sure to set up the lighting in a manner that guarantees your mare can see it.  Supplemental lighting will not be effective if it fails to register with the horse’s eyes.  So do not give your mare the opportunity to linger in the shadows, hang her head out into a barn aisle or find another way to avoid the light.  You will enjoy optimal results with the use of a timer to ensure consistency.

Common Supplemental Lighting Mistakes Horse Owners Make

Plenty of horse owners make the mistake of using dim lights.  Mares should be exposed to lights that are around 100 watts or more in power.  Provide your mare with a minimum of 100 watts and you won’t have to worry about whether photo-stimulation occurs.  Above all, do not forget to turn the lights on and leave them on.  Do not miss a single night.  Missing one or several lighting sessions makes it difficult for the mare to properly respond and alter to the seasonal change you are artificially creating.

If you notice any indications of heat from the lights, turn them off.  Continue to introduce daylight in place of the supplemental light as time moves forward and your mare will continue to progress.  Though there are certainly plenty of mistakes to make with supplemental lighting, those who put forth an honest effort will enjoy meaningful results.

Be Careful With Supplemental Lights

Though pregnant mares can be put beneath supplemental lights to spur a fast post-foaling cycle, there is always the chance of early foaling.  If the pregnant mare is foaling early in the year, consider putting her beneath the lights.  Using lights is especially  helpful if you intend to breed the horse back not too long after her pregnancy.  If you were to let nature take its course, it might take several months or longer for the mare’s body to regulate to its normal heat cycle.  However, if your mare has a reputation of foaling before anticipated, be especially cautious with supplemental lighting.

It will also help to track the mare’s cycles with regular ultrasound scans.  These scans will give you an idea as to how quickly progression is taking place.  If your mare is not progressing as quickly as expected, do not panic.  Certain horses are more responsive to lighting and other stimuli than others.

If you have any questions or concerns regarding your mare during these seasonal changes feel free to contact us. You can also follow Richard Schibell directly on twitter or LinkedIn to stay up to date. Don’t forget to keep checking for new articles on the Richard Schibell Racing blog!