Provision of shade is recommended by best practice guidelines for horses living in hot, sunny environments despite a lack of research focused on potential benefits of shade for horses. A previous study showed that horses with no access to shade showed greater rectal temperature and respiration rate, and they exhibited more sweat than horses that were completely shaded. Yet, this apparent benefit is dependent on horses choosing to stand under the shade provided.
The objective for this study, carried out by researchers at the University of California, Davis, was to assess horse preference for shaded and unshaded areas in hot, sunny, summer weather.
Twelve healthy, adult horses were used in three different trials, with four horses being used in each trial. The trials consisted of two days of acclimation and five to seven days of observation. Horses were housed individually in dry lots. The southern half of each pen was covered by an open‐sided shade structure. The amount of the pen shaded varied throughout the day with an average of 51% of the pen shaded throughout the day. Rectal temperature, respiration rate, skin temperature and sweat score were measured once in the morning, afternoon and evening each day. The horses’ behavior was also observed and recorded. The behaviors recorded were horses’ location relative to shade, and time spent walking, foraging and standing. Horses were considered to be “in shade” if at least two hooves were shaded by the shade structure.
Results showed that more horses were located in the shade and performed more walking and foraging behavior in the shaded area. In addition, horses spent more time at night beneath the shade structure than in the uncovered area. These results indicate that individual housed horses do prefer to utilize shade when it is available in hot, sunny environments. These results support recommendations for access to shade when developing best management practice guidelines for horses.
Summarized by Shanna Privatsky, University of Minnesota.