Strip grazing delivers more consistent nutrients than free grazing

(c) Sarah Shephard

A recent study has revealed that strip grazing can provide horses with a more consistent nutrient supply
compared to unrestricted grazing once rapid spring grass growth subsides. This finding adds further insight into the potential effectiveness of strip grazing as a tool for managing weight in horses.

The research, conducted by Dr. Annette Longland from Equine Livestock and Nutrition Services in collaboration with the WALTHAM™ Equine Studies Group and the SPILLERS brand, builds upon previous work by the same team. Earlier research* demonstrated that strip grazing could effectively restrict grass intake to aid in managing the body weight of pastured ponies, although the underlying reasons were not fully understood. This follow-up research highlights the benefits of consistent nutrient intake achievable through strip grazing.

 

In this study, twelve ponies were individually grazed in long, narrow paddocks specifically designed to provide herbage equivalent to 1.5% (dry matter) of the ponies’ body weight per day over a 28-day period from late June to late July, once the rapid growth phase of spring grass had finished.

 

For the first two days, all ponies were grazed on freshly mown "start paddocks" before being allocated to one of three grazing regimes for the duration of the study: unrestricted grazing (total allowance; TA group), or one of two strip grazing methods. In the first strip grazing method, a lead fence was positioned across the width of the paddock and moved daily to allow access to fresh grass. The second strip grazing method involved both a lead and a rear fence, with the rear fence moved the same distance daily as the lead fence.

 

Weekly evaluations were conducted to assess pasture nutrient levels and estimated digestibility.

 

The results showed that strip grazing provided herbage of more consistent nutritional quality throughout the trial compared to when ponies had unrestricted access to the same amount of original herbage. The findings also reiterated the potential value of strip-grazing as an effective tool for weight management.

 

Throughout the study, the start paddocks remained leafy and green, while the nutritional value of the remaining grass declined as it matured, consistent with typical trends for mixed-species pastures in the UK. Notably, strip grazing prevented the aggressive selective grazing observed in the total allowance (TA) group, where ponies consumed the more nutritious herbage early on, leaving less nutritious herbage for the latter part of the study period.

 

As a result, the calculated digestible energy intakes of the TA ponies in weeks one and two exceeded requirements by 42 % vs. 8 % by the strip-grazed ponies. Over the course of the study, the TA ponies gained three-four times more weight than their strip-grazed counterparts, with over 70% of the TA ponies’ weight gain occurring in the first two weeks. In contrast, strip grazed ponies gained significantly less weight overall at a more consistent rate.

 

“This study gives us some important practical take home messages regarding weight management and potentially the management of associated disorders such as insulin dysregulation and laminitis,” said Sarah Nelson, Product Manager at Mars Horsecare, home of the SPILLERS brand. 

 

“Strip grazing in this study prevented rapid weight gains by providing gradual access to fresh pasture of decreasing nutrient value and preventing aggressive selective grazing. This work shows how strip grazing, if carried out appropriately, can be an effective weight management tool especially once the very rapid, spring growth is over. However, it is important to remember that even strip grazing on high non-structural carbohydrate (NSC) containing pastures may not be suitable for some laminitis prone equids, especially those that are at high risk or at certain times of year.” 

 

For more details, see:

 

Longland, AC, Barfoot, C, Harris, PA. Strip grazing: 

Changes in biomass, nutrient content and digestibility of temperate, midsummer pasture by strip-grazed or ‘free’-grazing ponies, over 4 weeks.

Journal of Equine Veterinary Science (2023) Vol 131, 104957

https://doi.org/10.1016/j.jevs.2023.104957

 

*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

 

(Edited press release)