Hay Soaking: All Washed Up or Good Management?

This article is courtesy of Krishona Martinson, PhD, University of Minnesota.
Posted on Nutrena’s Blog

Soaking hay in water is a common strategy used to manage the nutrition of some diseased horses.  Current hay soaking recommendations include soaking hay for 30 minutes in warm or 60 minutes in cold water for removal of carbohydrates (Watts, 2003).  Soaking hay is commonly done to manage horse diagnosed with laminitis, Polysaccaride Storage Myopathy (PSSM), hyperkalemic periodic paralysis (HYPP), and chronic obstructive pulmonary disease (COPD).

  • Researchers have suggested that diets contain less than 12 and 10% nonstructural carbohydrates (NSC) for horses affected with laminitis (Frank, 2009) and PSSM (Borgia et al., 2009), respectively.
  • Reynolds et al. (1997) determined that a diet less than 1% K is necessary for horses diagnosed with HYPP.
  • Moore-Colyer (1996) determined that soaking hay for 30 minutes reduced respiratory problems for horses diagnosed with COPD or heaves.

However, how efficient is hay soaking, and are additional essential nutrients lost during the soaking process?  Researchers at the University of Minnesota set out to determine the impact of water temperature and soaking duration on removal of NSC, crude protein (CP), minerals, and dry matter (DM) from alfalfa and orchardgrass hays.

Four hay types were soaked, including bud and flowering alfalfa, and vegetative and flowering orchardgrass.  Individual flakes were submerged for 15, 30 and 60 minutes in 25 liters of cold (72°F) and warm (102°F) water, and for 12 hours in cold water.  A control (non-soaked) sample was also evaluated.  Water temperatures were determined by using the cold or warm only faucets, similar to practices implemented by horse owners and managers.  Subsamples of entire flakes were submitted for nutrient analysis at a commercial laboratory.

  • Prior to soaking, both alfalfa hays were below the 10 and 12% NSC threshold for horses diagnosed with PSSM and laminitis, respectively, and would not have required soaking. The orchardgrass hays were above these thresholds, however, after soaking for 15 to 30 minutes were at or below 10 to 12% NSC.
    • Although soaking hay for longer durations did further reduce NSC content, it is not recommended.  All horses, even diseased ones, require carbohydrates in their diet.
    • The severely limited NSC content in hay soaked for greater than 1 hour, combined with increased fiber amounts (fiber components are not water soluble, thus they are concentrated in soaked hay), brings into question the palatability and availability of nutrients in hay soaked for longer periods of time.
  • Crude protein leaching was variable in soaked hays, something other researchers have also observed (Moore-Colyer, 1996).  More importantly, previous research looked at the nutrient availability and quality of rained-on hay fed to steers and suggested the nitrogen remaining in rained-on hay is more stable, water-insoluble (Rotz and Muck, 1994), and possibly less digestible by ruminants (Licitra et al, 1996).  Additional research is needed to evaluate this concept when feeding soaked hay to horses.
  • Calcium (Ca) is not as prone to leaching during soaking compared to other minerals, and appears to be dependent on hay maturity.  As soaking duration increased, leaching of Ca increased in alfalfa bud and vegetative orchardgrass hays (immature hays).  However, soaking had no effect on Ca leaching in the more mature hays.
    • Conversely, magnesium (Mg) Mg and phosphorus (P) levels were reduced in all hay types as a result of soaking, with longer soaking durations leading to greater reductions.  Because Ca is not as water soluble as P, high Ca:P ratios were observed in hays soaked for  longer durations, specifically after 12 hours.
    • Ideally, Ca:P ratios should range from 1:1 to 3:1 (up to 6:1) in horse diets (NRC, 2007).  The high Ca:P ratios observed after longer soaking durations were exaggerated in alfalfa hays which had higher Ca:P ratios prior to soaking.
    • After 12 hours of soaking, a deficiency in P was observed and ranged from a shortage of 1 to 8 grams for a 500 kg horse in light work (NRC, 2007), and Krook and Maylin [32] suggested that osteochondrosis may be associated with excess dietary Ca.
  • Soaking both alfalfa and orchardgrass hay for 12 hours was necessary to sufficiently reduce K concentration to recommend levels prior to feeding horses diagnosed with HYPP (Reynolds et al, 1997).  Although K levels can be reduced by soaking, neither alfalfa nor orchardgrass hay is an appropriate option for horses diagnosed with HYPP due to the naturally high levels of K.

Owners should rely on forage analysis as the primary method of determining the appropriate hay for horses, especially when feeding horses diagnosed with laminitis, PSSM, HYPP or COPD.   Hay soaking for short durations (15 to 30 minutes in duration) is an acceptable management method, but should only be used if ideal hay is not available.  Hay should not soak hay for greater than 1 hour.  Soaking hay for long durations resulted in severely reduced NSC content, high Ca:P ratios, shortage of P in the diet and significant losses in DM.



By: Katie Jones, CVT

LaminitisLaminitis can be career ending or even life-threatening, causing deep seated fears in many horse owners. With continued research and the development of new treatment techniques, many cases have been resolved before life altering decisions had to be made. What is this condition? What can be done as horse owners to prevent the development of a laminitic episode?

Laminitis is inflammation of the laminae. The bones in the hoof are suspended within the hoof capsule by modified skin cells known as laminae (lamellae). The relationship between the laminae, bone, and hoof capsule is very similar to Velcro when fastened together. One end of the laminae is attached to the bone while the other is attached to the hoof wall. When working correctly, this relationship forms a shock absorber during a horse’s movements. When inflammation occurs in this delicate support system, it damages the integrity of this crucial bond. This leads to bone and soft tissue damage within the hoof and cuts off the laminae blood supply. Laminitis most commonly occurs in the front feet, but can also affect the hinds.

Laminitis can be triggered by numerous causes ranging from environmental factors to Laminitis1metabolic or systemic diseases. The predominant causes of laminitis are: metabolic or systemic in origin from excessive intake of lush green grass, Cushing’s disease, insulin resistance, secondary to infection, or excessive administration of specific drugs (corticosteroids); environmental factors such as grain engorgement; or mechanical factors such as excessive weight bearing on one limb due to a severe injury on the opposite leg. Lush pastures trigger laminitic episodes when the amount of sugar builds up in the blades on warm days with cool nights during optimal growing conditions. The sugar then triggers a metabolic event, stressing body and may result in laminitis.

There are vast inconsistencies in the progression and outcomes between horses in laminitic cases. Some will progress from barely lame to the hoof bone (coffin bone) rotating through the hoof sole rather quickly. Part of the variation lies in the individual animal as well as eating habits and metabolic issues. It is difficult to know which horses, when looking at them clinically, will progress to be more severely affected.

If your horse is exhibiting signs of laminitis, it needs to be treated as an emergency. Early intervention is critical and can dramatically reduce the likelihood of the laminitis progressing. A veterinarian will create a specific treatment plan for each individual case and it will be dictated by the progression of the disease. Treatment options may include: applying cushioned frog support, changing their diet, pain management practices, anti-inflammatories of various mechanisms, and limiting their exercise to stall rest.

If a joint effort between a veterinarian and a farrier is established with early treatment, laminitis will not always be a devastating disease. With early detection and good management practices laminitic episodes can resolve, returning the horse to normal daily functions.


Time to Ride

By: Katie Jones, CVT

“…horse people are really sick people”Chicken Soup for the Horse Lover’s Soul

Time to Ride3For many of us, we have been horse-crazy from the moment we received our first stuffed animal horse in our crib. Many kids will fall in love with horses at an early stage but will eventually out grow it; however, others are plagued for life. In this day and age, life is planned out by phone schedules and free time is limited due to the demands of work, school, other commitments, and family time.   With all the new technology advancements, digital entertainment is far more convenient and cheaper then an active lifestyle. Sadly, this specifically holds true in the horse industry where there has been a general decline in the number of people owning and working with horses. Many equine businesses depend on the continued growth within the equine industry, so for all of us, maybe it is time to reconnect with horses.

Horses can bring the family together in an activity that is physical, therapeutic, and pure joyful. Time to Ride is a program whose main purpose is to help people get reconnected with horses through different avenues. It is coordinated by the American Horse Council in cooperation with other equine organizations and breed associations to provide opportunities to individuals and their families close to home. Time to Ride provides tons of information on barns and events hoping to influence individuals to add more horse experiences into life.  They offer a great way to quickly connect with businesses around specific areas.

Trail Riding

Time to RideTrail riding is not limited to family vacations in other parts of the country; it can be a great family outing even close to home. Trail riding provides a great way to experience the great outdoors and gain confidence through a guided ride with horse. Contact a local stable or ranch to find a trail riding opportunities near you.

Blog post on traveling with horses in Minnesota.

Lessons & Camps

Time to Ride2Lessons allow a consistent equine learning experience, occasionally with the same horse. Lessons are a terrific way to learn a particular riding discipline or to try several in order to find the right fit before committing to buying or leasing a horse. Those with busy lifestyles or numerous time demands in life will find lessons allow flexibility in enjoying horse time without the full commitment of owning a horse. To get the best learning experiences, there are many resources available to find a great trainer and barn just for you.

Horse Events

Time to Ride1Minnesota has many horse events; everything from rodeos to eventing. Running Aces is a Harness Racing track located near Forest Lake and Canterbury Park is a Thoroughbred and Quarter Racing track located in Shakopee. Both are open May to September with weekly live racing to enjoy and offer occasional family days, which have additional attractions geared towards the whole family.

The Minnesota Horse Expo is held each year at the end of April at the State Fair Grounds in St. Paul. The expo has breed demonstrations, shopping, tack swaps, informational speakers, and a large discipline variety of Shows. Many of the breed disciplines and individual businesses who participate in the Expo have Facebook pages where events are posted.

There are countless options to get involved with horses. If after looking at the Time to Ride 4_02site you have not found the right match for yourself or your family, ask around. The equine industry is still fairly large in Minnesota and is full of people willing to help you find the perfect nitch.

If you are a horse business that would like to be listed with Time to Ride website, you can register here. Registration verification may take up to 30 days. Watch for a confirmation email from Time to Ride. Once registered, please share with others your business and the Time to Ride website in order to help promote this community. In addition, if you would like to be kept up to date on events and grants from Time to Ride, make sure to sign-up for their newsletter to receive the latest information sent straight to your email.

Anoka Equine Veterinary Services does not endorse any of the facilities, businesses, organizations, activities or events mapped, listed on, or linked to the Time to Ride web site. Reference to such entities does not constitute or imply any endorsement or recommendation by Anoka Equine Veterinary Services.

Anoka Equine Veterinary Services is not responsible for any representation made by any such entities or the contents of other web pages referenced, the representations made thereon or any representations made by such entities. Anoka Equine Veterinary Services is not liable for the content of mapping information, or for the consequences of any actions taken on the basis of the information provided by mapped entities, businesses or events.  Anoka Equine Veterinary Services has not inspected any of these entities or facilities.  The reader should not assume that the information is factual or reviewed by Anoka Equine Veterinary Services. Anoka Equine Veterinary Services makes no warranties or guarantees as to any equine facility or operation’s safety standards, animal husbandry practices, experience in providing whatever services it purports to provide, carriage of liability insurance, or suitability as a provider of horse riding or handling instruction. Anoka Equine Veterinary Services does not assume any responsibility for misinformation provided by any facilities mapped on the website, and all information is subject to change without notice. Links from the pages on this website send visitors to external Web sites as a service to visitors and do not constitute an endorsement by Anoka Equine Veterinary Services.

Anoka Equine Veterinary Services notes that all equine activities, including riding, are inherently risky. Any equine activity carries with it potential hazards which are beyond the control of Anoka Equine Veterinary Services.