Gestation of Horses in comparison to humans

Anatomy / Pedigree
April 9th, 2020

Following a suggestion from a Foal Patrol follower, here is a more in depth overview of the gestation of horses in comparison to that of humans.

The cycle of breeding, gestation and delivery follows a specific timeline for thoroughbred horses. Below is some background on that timeline and how Three Chimneys Farm ensures the broodmares are safe and healthy. The gestation of a horse is 330-345 days. With an ultrasound, at 14 days after conception, a horse embryo can be detected. The gestation for humans is generally stated as 280 days, but actual conception does not occur until day #14, and so the actual gestation of a human (from conception to estimated delivery date) is 266 days. By classical counting, a human embryo can be seen on ultrasound at “5 ½ - 6 weeks of gestation”, but that is actually 3 ½ - 4 weeks after actual conception. A foal is generally 100-150 lbs. at delivery (depending on the size of the brood mare) and human newborns generally range from 6 ½ - 8 lbs. The gestation of a horse is significantly longer than the gestation of humans, and this is one of the main reasons that foals are significantly larger than newborn humans.