Strip-grazing: Reduces pony dry matter intakes and improves body weight

I almost did not include this study here because it is not practical for the average horse owner to estimate the dry matter yield of their pasture so that they can design an appropriate paddock size and movement. However, the message is important and with careful and frequent measurement of the heart girth length you could build the information needed to create paddocks of appropriate size to achieve the necessary weight loss (or prevent gain). Start with a notebook to keep current heart girth, the size paddock you start with, and the condition of the forage on the pasture. At first it will be hit or miss reaction but with time you should be able to become proactive to help achieve a desirable body condition.
DrO

Strip-grazing: Reduces pony dry matter intakes and changes in bodyweight and morphometrics
Equine Vet J. 2020 Dec 28.
Authors
Annette C Longland 1 , Clare Barfoot 2 , Patricia A Harris 3
Affiliations

1 Equine and Livestock Nutrition Services, Tregaron, Ceredigion, Wales, UK.
2 MARS Horse Care UK Ltd, Old Wolverton, Buckinghamshire, UK.
3 WALTHAM Petcare Science Institute, Waltham-on-the-Wolds, Leicestershire, UK.

PMID: 33369770
DOI: 10.1111/evj.13416

Abstract

Background: Obesity can negatively impact upon equine welfare and bodyweight (BW) of pastured equines is often difficult to manage.

Objectives: To compare the effects of three restricted grazing regimens on changes in pony BW and morphometric measurements STUDY DESIGN: Randomised experiment.

Methods: Twelve mature ponies were individually grazed in 10m wide, rectangular, electric fenced paddocks. The dry matter (DM) herbage yield of each paddock was determined, and paddock length adjusted on day 1 to provide 1.5% of individual pony BW as herbage DM daily, for 28 days. There were four ponies per treatment. Treatments were: total paddock area (TA) and strip grazing treatments, SG1 and SG2. SG1 had a ‘lead’ fence spanning the paddock width being moved a set distance along the paddock length daily to provide 1.5% of pony BW as fresh pasture DM (as determined on day -1). SG2 also had a ‘back fence’ 7-12m behind the ‘lead’ fence which was moved the same distance as the lead fence daily. Dry matter intakes, and changes in BW, cresty neck score (CNS), body condition score (BCS), heart girth (HG), belly girth (BG), and rump width (RW) were compared between treatments.

Results: Mean (±SD) calculated pasture DM intakes (as % BW/d) by TA ponies were 2.33±0.501, being significantly higher (P<0.05) than 1.82±0.429 (SG1) and 1.52±0.423 (SG2). Mean percentage BW changes were higher (P<0.05) for TA ponies at 4.82±1.355 vs. 1.16±0.389 (SG1) and 1.54±1.345(SG2). SG1 and SG2 pony BW changes were not significantly different. TA, but not SG1 or SG2 animals showed significant (P<0.05) increases in BCS (0.94±0.32), CNS (0.5±0), RW (2.11±3.6) and BG (4.15±2.29). SG1 and SG2 ponies showed significant (P<0.05) decreases in HG (-0.05±2.12) and BG (-5.53±4.89) respectively.

Main limitations: Small sample size.

Conclusions: Strip grazing limited pony bodyweight gains and upward changes in morphometric parameters.