Everybody loves a good back scratch, including your horse, right? Scratching of the withers has been scientifically proven to reduce a horse's heart rate, but a good scratch might not be enough to communicate to your horse that you're happy with what he's just learned and that you want him to do it again next time.

According to new research by French equitation scientists, presented at the sixth International Equitation Science Conference in Uppsala, Sweden, on Aug. 2, rewarding horses with food, rather than physical contact, is most effective.

"Overall, it appears that scratching the withers may not be considered a primary positive reinforcement for horses," said Carol Sankey, MSc, a PhD candidate in ethology (the study of animal behavior) at the University of Rennes in western France. "In fact, some horses don't seem to like it much it at all."

In previous studies also described at TheHorse.com, Sankey compared food rewards to negative reinforcement and food reward to no reinforcement at all; in both cases the horses' training programs were significantly improved when food reward was used. The food-rewarded horses also remembered the training longer and had friendlier contact with humans.

But now Sankey and her colleagues have addressed the question of which kind of positive reinforcement works better: physical contact—wither scratching—which is known to reduce heart rates (suggesting the horse enjoys it), or food (in this case, carrots). They put the question to the test by training 20 Konik horse yearlings to st