Spook tests: Diet effects in action

After researching how a diet high in sugar and starch effects insulin and glucose, it made Middleburg Agricultural Research and Extension Center researchers a little curious. Does diet amplify a horse’s reaction to stimuli?

Now many horse owners agree: there are some horses that are much more hyper than others. Some are great to take on a trial ride and some you’d rather let explode out of the starting gate. This difference in temperament can be attributed to what characteristics the horse was bred for: Thoroughbreds for racing; quarter horses for dependable ranch work, for instance.

A few years ago the center researchers took a group of Thoroughbreds - characterized as being hot-blooded - and split them into two study groups: one that was fed a low 3 percent fat diet and one fed a high 10 percent fat diet.
Then researchers exposed the horses to a series of “spook tests,” and measured spontaneous activity with pedometers placed on the horses’ legs. They tested each horse’s movement in its stall throughout the week, and they tested reactivity to pressure, noise, and visual stimuli.

The visual stimuli test was the most unusual. The researchers walked a horse up and down the barn aisle several times. The horses would meander back and forth, not paying the activity much mind.

Then: Woosh! A large, vibrant umbrella would open just beside them on the final pass. Naturally, many spooked — but to varying degrees.

“The study concluded that when horses were fed the low fat diet they walked more in the stall and reacted more excitably to pressure, noise, and a unique visual stimuli,” says Carey Williams, Ph.D. candidate in the animal and poultry science.

These findings underscore the old saying, “Feeling their oats.”

“I will say that most riders and trainers who have excitable horses don’t need this study to confirm the results,” Williams says. “They can see for themselves that after they switch to fat their horses become quieter and easier to handle.”