Factors Affecting Spontaneous Activity in Young HorsesBy Dr. Kathleen Crandell · October 21, 2011
Have you ever wondered if the type of feed your horse eats affects how much he moves during the day?
Little research has been done on the effects of diet on behavior, and specifically on spontaneous activity. In a study with Arabian horses on a high-starch versus a high-fat diet, there was a difference seen in the amount of reactivity to external stimuli. However, no research has been performed that investigates the effect on reactivity or spontaneous activity when fed a high-fiber diet as opposed to a high-starch diet. Little is known as well on how normal stressors that a growing horse is exposed to affects the activity level. The effects of diet, weather, and routine veterinary treatments on spontaneous activity in horses through their first two years of life were recently studied.
Twelve Quarter Horse foals were fed either a high-starch diet (29.4% starch, 6.5% fiber, 5% fat) or a high-fiber, high- fat diet (16.6% starch, 13% fiber, 9.5% fat) for two years. The foals were on the same diets as their dams and were creep fed with the same feed before weaning. After weaning they were fed the concentrate at 3.5 kg (8 lb) per day with grass hay. Each foal was fitted with a GPS tracking device, which they wore during their daily turnout on pasture for eight hours a day.
Two years of spontaneous activity was recorded for each foal with the GPS devices. During those two years, the foals experienced normal stressors: weaning, castration, vaccination, and changes in the weather. The effect of diet and the stressors was correlated with the number of steps and the total distance traveled. There was no difference in the amount of spontaneous activity seen between the two different diets. However, the amount of spontaneous activity decreased after weaning, vaccination, and during hot weather. The amount of activity increased after castration.
Diet does not appear to have any effect on the activity level of the growing horse, contrary to popular opinion. The surprising observations in the study were the increase in activity after castration yet a decrease in activity after weaning, when just the opposite would be expected. The researchers speculate that spontaneous activity decreased after weaning because the foals did not have their dams to follow around and may have been depressed from the separation. Increased activity after castration is difficult to explain except that the colts might have felt better if moving. In contrast, the vaccinations may have made the foals a little muscle sore and less willing to move around.
This study was presented at the 2011 Equine Science Society Symposium in Murfreesboro, Tenn. The proceedings from this symposium are available from the Journal of Equine Veterinary Science.
