Want to give your foal the best chances for a long sport career? Choose your uterus wisely. Researchers in France have determined that the uterine environment—including how we feed the mare and, if it’s an embryo transfer, which mare we use—can have a significant effect on the foal’s future bone health, energy metabolism, and osteochondrosis risk.

“The concept of developmental origins of health and disease (DOHaD) issues is now well-established in humans and domestic animals and certainly applies to horses, as well,” said Pauline Peugnet, PhD, of the French Agricultural Research Institute, in Jouy-en-Josas. Peugnet presented her work at the 41st French Equine Research Day, held March 12 in Paris.

“Studies using embryo transfer to modify fetal growth have clearly shown the impact of prenatal development conditions on important parameters for the sports career of the animal, such as glucose homeostasis (metabolic syndrome) and osteoarticular (bone and joint) health,” Peugnet said.

Last year, Peugnet unveiled her research on transferring embryos of different-sized breeds into three different sized mares (ponies, saddle horses, and draft horses) and found significant effects on fetal growth, both in utero and after birth. Peugnet and her team have now taken data from that “FOETALIM project” and looked at how the uterine environment from “restricted” and “enhanced” gestational situations (i.e., large-breed fetuses growing in small-breed uteri, and vice versa, respectively) affects metabolism, specifically insulin resistance.

They found that pony fetuses in a very