A study of horses with equine metabolic syndrome showed that weight loss, managed by their owners at home, reduced insulin resistance and susceptibility to laminitis.
The researchers said recent research provided proof that conscientious owners really can help reduce the risks posed by obesity in ponies.
Clinical studies have already identified that calorie restriction and increased exercise are the mainstays of treatment for the syndrome. However, there is potential for poor owner compliance, which has historically made it difficult to accurately monitor the effects of owner-managed weight loss.
The new study, published in the Equine Veterinary Journal and one of the subjects of the journal’s latest podcast, has shown that owners of ponies with equine metabolic syndrome were able, with veterinary support, to implement highly effective weight loss programmes and thus improve insulin sensitivity and reduce the risk of laminitis.
Equine metabolic syndrome is a complex condition, defined by clinical consensus as obesity, insulin resistance and an increased susceptibility to laminitis. Insulin resistance or dysregulation is the underlying symptom, probably underpinned by genetic predisposition and driven by obesity, ultimately resulting in laminitis.
The study, “Treatment of equine metabolic syndrome: a clinical case series”, was conducted by vets at the universities of Liverpool and Edinburgh to determine whether significant weight loss and improvements in insulin sensitivity can be achieved in horses and ponies with the syndrome, managed by their owners at home under veterinary guidance.
A total of 19 horses and ponies either suspected to have the syndrome and/or a history of laminitis were included in the study. They underwent a clinical examination, as well as basal and dynamic endocrine testing.
Owners were then given individually tailored diet and exercise programmes to follow for between three and six months.
They were given daily support from vets throughout the period.
After the treatment, clinical examination and endocrine tests were repeated and results compared to the initial assessment. All but one showed a significant reduction in weight, accompanying reductions in insulin levels and thus reduced susceptibility to laminitis.
Project co-ordinator Ruth Morgan, based at the University of Edinburgh said her team used the combined glucose-insulin test to monitor horses in her study. This was a very accurate way to assess insulin function, but required intravenous catheter placement and multiple blood samples.
As alternatives to help identify ponies at risk of laminitis and monitor and manage them more effectively at home, vets can also use in-feed oral glucose and oral sugar tests. These relatively new tests can be used to assess insulin sensitivity, simply by feeding a specified level of glucose or corn syrup and then taking a single blood test.
Recent research, also published in Equine Veterinary Journal and discussed in the podcast by Sarah Smith of the Royal Veterinary College, indicates that the two tests agreed in most cases but further research is required to identify the most appropriate test.
Morgan said: “Our weight loss work shows that if owners are educated, informed and encouraged by their vets they can effectively induce weight loss and improve insulin resistance. We found that the key to compliance is the individual tailoring of a weight loss programme for each horse.
Smith said: “Our work will help provide vets and owners with simple and practical methods to assess horses’ insulin function and monitor the impact of diet and exercise programmes.
“At the moment, we cannot say one oral test is more appropriate than the other, the key thing is to use the same test repeatedly if an individual horse is monitored over time.”
Equine Veterinary Journal editor Celia Marr continued: “We know that most owners are keen to do the best for their horses but sometimes they lack the knowledge or facilities to implement a weight loss programme easily. This study has shown how consistent, responsive support from a vet, coupled with innovative individual methods for weight loss can make all the difference.”
Morgan’s weight loss tips:
- Ask your vet for advice before embarking on a weight loss programme.
- Restrict overall intake and take account of everything the horse eats – for example, feed hay at 1.5 percent of bodyweight, feeding at least twice a day.
- Have forage analysed – you need hay with a low sugar (water-soluble cardohydate) content.
- If the water-soluble cardohydate is high, soak the hay to reduce water soluble carbohydrate content, but you may need to increase the bulk of the diet to up to 2 percent bodyweight if the hay is soaked.
- Cut out all treats and additional feeds but do use a high quality balancer.
- As long as the horse is sound, provide daily exercise, regularly increasing the horse’s heart rate to 100-150 beats per minute if you can, which will burn calories. This will mean trotting and cantering to induce puffing and sweating rather than just walking.
Treatment of equine metabolic syndrome: a clinical case series RA Morgan, JA Keen and CM McGowan DOI: 10.1111/evj.12445
Comparison of the in-feed glucose test and the oral sugar test S Smith, PA Harris and NJ Menzies-Gow DOI: 10.1111/evj.12413
The August Equine Veterinary Journal podcasts are available free online here.