Research has confirmed that different horse breeds have different capacities for weight loss, with standardbred horses in a study losing condition much more readily than Andalusians or ponies.
Further work is planned to find out whether these breed variations are related to insulin sensitivity or other hormonal differences.
The findings in the study, Comparison of weight loss, with or without dietary restriction and exercise, in Standardbreds, Andalusians and mixed breed ponies, will help to improve the effectiveness and safety of equine weight loss programmes in the future.
The research was conducted by the University of Melbourne’s Faculty of Veterinary Science in Australia, in collaboration with the Waltham Equine Studies Group.
It will be presented at the Equine Science Symposium, New Mexico in May 2013.
Twelve obese animals, comprising four standardbreds, four ponies and four Andalusians, all with body condition scores of 7 to 9 out of 9, were initially kept on ad lib hay for 20 weeks and then fed individually on a restricted diet of 1.25 per cent bodyweight of hay for up to 12 weeks.
Two from each breed group were exercised daily on a horse walker.
Dietary restriction was stopped when each horse reached a body condition score of 5, which occurred between 4-6 weeks in the standardbred group.
However, even after the full 12 weeks of dietary restriction, the ponies only dropped from a body condition score of 7.1 to 5.9 and the Andalusians from 6 to 5.2.
Nutritionist Clare Barfoot and the research and development manager at equine nutrition firm Spillers said: “The ponies and Andalusians retained condition on ad-libitum hay and were relatively resistant to body fat loss even when hay was reduced to 1.25 per cent body weight.
“Daily exercise also didn’t have much impact on these two groups. However, the standardbreds lost significant amounts of weight and body condition when maintained just on ad-lib hay and subsequently lost weight much more rapidly on the restricted diet.
Comparison of weight loss, with or without dietary restriction and exercise, in Standardbreds, Andalusians and mixed breed ponies: S.J. Potter, N.J. Bamford, and S.R. Bailey, Faculty of Veterinary Science, The University of Melbourne, Victoria, Australia, P.A. Harris, Equine Studies Group, Waltham Centre for Pet Nutrition, Leicestershire, UK