For many horses and ponies, grass is the main (or only) source of calories in the diet – it’s also one of the hardest for owners to control! A 250kg pony living out at grass may consume enough energy (calories) to fuel a 500kg racehorse – equivalent to more than half a bag of conditioning cubes every day! Restricting grass intake is an essential part of many weight management programmes but is strip grazing an effective solution? SPILLERS research conducted in collaboration with Dr Annette Longland of Equine Livestock and Nutrition Services in Wales 1, set out to answer this very question…

Science puts strip grazing to the test

Twelve ponies were turned out in individual paddocks for 28 days. All paddocks were 10m wide, but the length of the paddock was adjusted to be able to provide (at the start of the study) 1.5% of the ponies’ bodyweight (dry matter) in grass for 28 days. To test the effect of strip grazing on weight gain, each pony was assigned to one of the following management practices or ‘treatments’ (4 ponies of similar height, weight and body condition per treatment):

Total allowance.

After a 2-day adaptation period ponies were given access to their whole paddock

Strip grazing without a back fence

A single ‘lead fence’ was positioned across the width of the paddock and after an initial 2-day adaptation period moved 1/26th of the remaining length per day to provide controlled access to fresh grass

Strip grazing with a back fence.

After an initial 2-day adaptation period the lead fence and a ‘back fence’ was moved by 1/26th of the remaining length per day to allow fresh access to grass without increasing size of grazing area

The all-important results

Strip grazed ponies gained significantly less weight than ponies in the total allowance group, regardless of whether a back fence was used. In fact, strip grazing without a back fence was no less effective than strip grazing with a back fence, even though the grazing area got larger every day.

Why is this research important?

Horse owners have used strip-grazing in various forms for decades but there has been little work to look at how effective such a practice is. This research clearly shows that under controlled conditions, strip grazing can reduce the rate of weight gain in ponies living out at pasture. We hope that this and future work will help to improve the practical advice we give to owners and ultimately, the health and welfare of horses and ponies.

Next steps

The next stages of this research are already under-way and will investigate other aspects of strip grazing including its effect on voluntary exercise (do strip grazed ponies spend less time moving around for example?), grazing behaviour and pasture wear and tear. Watch this space!

Want to know more?

This is research is published online in the Equine Veterinary Journal.

Reference

Longland, AC, Barfoot, C, Harris, PA. Strip-grazing: Reduces pony dry matter intakes and changes in bodyweight and morphometrics. Equine Vet J. 2021; 00: 1– 8. https://doi.org/10.1111/evj.13416

For more advice on managing your horse’s grass intake contact the SPILLERS Care-Line