We already know that cardiac recovery time in endurance horses is related to their ability to perform well in races. But what we didn’t know—until now—is that recovery time is a heritable trait.

French researchers have determined that we could breed selectively for recovery time in endurance horses, as this trait gets passed on through genes.

“Cardiac recovery time in endurance racing appears to be strongly influenced by genetics, so a selection based on cardiac recovery time could be a supplemental physiological characteristic to take into consideration to improve the breeding selection of endurance horses,” said Eric Barrey, PhD, of AgroParisTech, the University of Paris-Saclay, and the French National Agricultural Research Institute.

However, for such a breeding opportunity to realistic, race organizers should record horses’ cardiac recovery time during events to obtain official data, he