Feeding horses high starch grain (such as oats) may make them more reactive

17 Feb 2015
Just like candy makes kids hyper, feeding horses high starch feeds (feeds high in sugar), may make them more reactive.
To be clear sugar for horses isn’t quite the same as sugar for humans. Feeds that cause glycemic spikes in horses are feeds that are highly digestible for the horse, for example, oats and other high starchconcentrate cereal grains.
Researchers at the Royal School of Veterinary Studies in the UK found that horses being fed a high starch diet had a more reactive heart rate during a handling test than those on a high fiber diet.
The horses on the high starch diet also showed more interrupted patterns of eating when exposed to a stressful sound, suggesting they may have been more anxious.
Interestingly, there was no difference in handling behaviour between the two diets. The researchers have hypothesized that this may be due to the experienced nature of the horses (part of an Agricultural College) and handlers. More research is needed in this area.
Reference
Bulmer, L. S., McBride, S. D., Williams, K., & Murray, J. A. M. (2015). The effects of a high-starch or high-fibre diet on equine reactivity and handling behaviour. Applied Animal Behaviour Science.