Establishing a Foal’s Healthy Gut Microbiome - mare and foal photoThe horse is a seasonal breeder meaning that natural mating occurs during certain times of the year to ensure that the timing of birth is optimal for survival with regard to ambient temperature, food and water availability, and even changes in the predation behaviors of other species.  Seasonal breeders are controlled by the length of daylight, i.e. the photoperiod, and can be divided into long day breeders, e.g. the horse, that start cycling when the days get longer (spring) and short day breeders, e.g. deer and some breeds of small ruminants, that start cycling when the days get shorter (fall). The length of photoperiod can be manipulated in order to hasten the onset of the breeding season. This is a popular management technique used in many breeds, so foals can be born as close to the standardized January 1st birth date as possible. It is also common with show or halter horses, with the goal being to maximize maturity for age determined competition.