Turn your horse out worry-free this spring

26 May 2021 (Horse health news)

Turn your horse out worry-free this spring

Coming into spring can be a worrying time when thinking about turning your horse or pony out to grass again. It’s great to get them out into their summer fields, but how much rich lush grass is safe when it comes to laminitis? Research shows that this fear is not unwarranted – more diagnoses of laminitis are made in the spring and summer months,1,2 making the transition a crucial time for your horse’s health.

The first thing to understand is why the grass is such a risk for laminitis. The exact mechanism is not fully understood, but we know that as grass is digested in the gut the sugars are absorbed and can cause a spike in blood insulin levels. This insulin spike, in predisposed individuals, can cause laminitis. But what causes some individuals to be predisposed to laminitis? Why does a thoroughbred not suffer as frequently as a native breed pony? Why do two horses in the same field respond differently to the same grass intake? We think this comes down to genetics: some horses and ponies have a higher insulin peak after eating grass and are therefore more at risk of developing laminitis.4

Contrary to popular belief turning out for shorter periods of time does not limit their intake. A pony can learn to eat just as much as normal (and sometimes more) in a short period of time if a time limit is the only strategy implemented.3

So what can you do to limit the risk? You can’t change your horse’s genetics, but you can manage their laminitis risk level as you re-introduce them to spring pastures. There are 3 main strategies for this: limit their grass intake, manage underlying hormonal disease and close monitoring.

  1. Limiting the grass intake: this can simply be achieved by strip grazing. However, perimeter grazing encourages more movement and therefore energy expenditure. Grazing muzzles also slow intake – but be careful as some ponies can still eat large quantities through them. Or the more ingenious ones can remove them entirely!
  2. Managing underlying hormonal disease: being aware of the risk factors for laminitis in your animal is vital. Equine Cushing’s disease and Equine Metabolic Syndrome (EMS) are the two main causes of laminitis.1 Fortunately, both of these conditions are manageable.  Keeping Equine Cushing’s disease under control requires a daily medication and management adaptations. The medication dose should be assessed every 6 months with a quick blood test. It is a good idea to book these in with your vets in autumn and spring. They can then give you advice on adjusting the dose if necessary. Laminitis risk management for horses with Equine Cushing’s disease tends to be the same as for those horses with EMS.  Managing Equine Metabolic Syndrome can be a challenge. The principles are simple, but as with ourselves, it’s never easy to change a habit! The mainstay of management is exercise and weight management. Dr. Terresa Hollands from the University of Surrey has produced a fantastic newsletter on nutrition for these EMS and Cushing’s horses: (https://www.careaboutcushings.co.uk/resources/downloadable) Exercise is crucial as this improves your horse’s response to insulin. As little as 30 minutes 3 times a week of fast trot-canter work can have beneficial effects on your horse.4 If your horse is currently suffering from laminitis or if you need more guidance then please speak to your vet and they can create a personalised exercise plan for you.
  3. Close monitoring: Horses with a predisposition to an insulin spike tend to have some degree of underlying laminitis that is intensified by the lush grass in spring. This means that with close monitoring you can pick up the early signs of laminitis before it gets worse.4 We have a useful check list that you can follow and fill out. By becoming familiar with your horse’s check and following the same routine each time you can ensure your horse stays happy and sound.

Understanding the risks posed by lush grass and the strategies you can use to limit the laminitis risk in your horse should make spring turn-out a less stressful time for both you and your horse, and will hopefully mean that you can both enjoy the fresh air and sunshine that we’ve all been looking forward throughout the long winter months!

1. De Laat MA, Sillence MN, Reiche DB. Phenotypic, hormonal, and clinical characteristics of equine endocrinopathic laminitis. J Vet Intern Med 2019;33:1456–1463.

2. Menzies-Gow NJ, Katz LM, Barker KJ, et al. Epidemiological study of pasture-associated laminitis and concurrent risk factors in the South of England. Vet Rec 2010;167:690.

3. Ince J, Longland AC, Newbold JC, et al. Changes in proportions of dry matter intakes by ponies with access to pasture and haylage for 3 and 20 hours per day respectively, for six weeks. J Equine Vet Sci 2011;31:283.

4. Durham AE, Frank N, McGowan CM, et al. ECEIM consensus statement on equine metabolic syndrome. J Vet Intern Med 2019;33:335–349.