Supporting your horse in spring
Professor Jo-Anne Murray
PhD, MSc, PgDip, BSc (Hons), BHSII, RNutr, PFHEA University of Glasgow Veterinary School
Environmental and management changes in springtime
The wet weather in the UK has meant that many horses have been stabled more than they normally would be over the winter months and now that the weather has improved you may be turning your horse out for longer periods of time or even 24/7. This is a change in management and feeding as your horse will go from being stabled and fed forage to being at pasture and having access to grass. Whilst that is good for the horse’s welfare to have more turnout, it is advisable that this is built up gradually as a sudden change of this type can also increase the risk of colic. Furthermore, if you have gradually moved from stabling to 24/7 turnout then it’s also important to remember that pasture constantly changes in response to the environment and therefore whilst you may not change anything in terms of their management, the changes that are taking place in the pasture can be dramatic at times and this can impact on your horse’s gut health.
Water soluble carbohydrate (WSC) levels in spring pasture
Another consideration associated with pasture at this time of year is the water soluble carbohydrate (WSC) content. It is well known that WSC levels are higher at certain times of the year (spring/summer) and under certain conditions. The current climate in the UK, which is bright sunlight and dry conditions means that the WSC content of pasture is likely to be high. This is because plants produce sugars when sunlight is available, which they use for growth, but when there is a limited water supply then growth is limited, and this results in high levels of WSC being stored in the grass. Fructans are a component of the WSC fraction of grasses, but horses do not produce any enzymes in the small intestine to digest fructans and instead these rapidly fermented sugars pass to the large intestine where they can disrupt the hindgut environment in the same way a large amount of undigested starch would. Large intakes of fructan can increase the risk of your horse developing colic; therefore, a sudden change from being stabled to being turned out 24/7 coupled with a high WSC content of pasture substantially increases you horse’s risk of colic and other issues, such as laminitis.