Effects of Soaking Hay for HorsesBy Kentucky Equine Research Staff · November 23, 2016
A traditional way of reducing dust in hay involves soaking it, and this is an especially useful management tool for horses with respiratory sensitivity or breathing problems. However, soaking hay is difficult and not always a practical recommendation for horse owners. The nutritional impact of soaking hay can be significant and is often overlooked, especially if the hay is of marginal quality.
Do the pros of soaking hay outweigh the cons?
Researchers found that dunking hay in a bucket of water and feeding immediately afterwards significantly reduced dust concentration compared to dry hay, explained Catherine Whitehouse, M.S., a nutrition advisor for Kentucky Equine Research (KER). Completely immersing the hay in a dunking fashion was just as effective as soaking hay for many hours1.
“In other research trials, respirable dust was decreased by more than 92% after soaking 10 or 30 minutes, thus lending credence to soaking as an effective management strategy in keeping horses with respiratory compromise comfortable2,” said Whitehouse.
Soaking hay affects its nutritional value in a time-dependent manner. Submerging hay for longer than 30 minutes has a negative impact on nutritive quality, reducing the concentration of certain minerals. Two studies reported there was little to gain regarding reduced respiratory challenge and much to lose if hay was soaked for longer than half an hour2,3. Soaking hay for 30 minutes effectively minimized its respirable challenge and maintained maximal nutritional value.
Omega-3 fatty acids (docosahexaenoic acid or DHA and eicosapentaenoic acid or EPA) have been found to promote and improve respiratory health in horses and, through their immunomodulatory activities, can help reduce the severity of allergic reactions. For these horses, supplementing daily with 2-3 oz of EO•3, a source of marine-derived omega-3s researched by KER. Because EO•3 contains a direct source of DHA and EPA, it is preferred to plant-based omega-3 supplements such as flaxseed.
“Managing horses with respiratory difficulties can be demanding on owners, but building in a few extra minutes for plunging or soaking hay in water is an easy way to reduce wheezing, coughing, and breathing effort,” summarized Whitehouse. “Plus, it elevates quality of life.”
1Clements, J.M., and R.S. Pine. 2007. Respirable dust concentrations in equine stables. Part 2: The benefits of soaking hay and optimising the environment in a neighbouring stable. Research in Veterinary Science. 83:363-268.
2Blackman, M., and M.J.S. Moore-Colyer. 1998. Hay for horses: The effects of three different wetting treatments on dust and nutrient content. Animal Science. 66:745-750.
3Moore-Colyer, M.J.S. 1996. Effects of soaking hay fodder for horses on dust and mineral content. Animal Science. 63:337-342.