The effect of changing diet on gastric ulceration in exercising horses and ponies following cessation of omeprazole treatment was conducted by Nanna Luthersson (Hestedoktoren, a private practice in Denmark) and Coby Bolger (Horse1 Spain), with colleagues from the University of Madrid and Glasgow, in collaboration with Spillers and the Waltham Equine Studies Group.
The study evaluated the effect of dietary change in combination with omeprazole treatment and after the cessation of treatment.
The 32 horses in this part of the trial had been diagnosed with significant equine squamous gastric disease (ESGD) and were in hard work.
On a random basis one of each pair was assigned to a specified low starch, fibre-based diet consisting of their own forage alongside a restricted starch, high fibre, high energy cube (Spillers HDF Power Cubes, which are commonly used in racing yards) and a high oil, low starch, chopped alfalfa based feed (Winergy Equilibrium Growth) and the other stayed on their original diet. All animals were scoped before, after the recommended course of omeprazole treatment and then six weeks after the omeprazole finished.
The horses in the no diet change group improved significantly with the omeprazole but when the treatment was stopped many regressed. Overall, by the end of the trial they were not significantly different to when they had started.
However, the horses in the dietary change group overall showed significantly improved ESGD scores, not only following the omeprazole treatment but also after the treatment had stopped. This showed that a change in diet was able to help maintain the beneficial effect of omeprazole even after the omeprazole was removed.
The study achieved an award in 2016 for research in horse welfare from the Fundación para la Promoción del Deporte Ecuestre, Spain.
Clare Barfoot RNutr, the research and development manager at Spillers, said: "This exciting work confirms what we suspected; that whilst appropriate dietary change can provide additional support to medical treatment for EGUS most importantly it can help maintain better gastric health post medical treatment."
Last year the British Equestrian Trade Association, in consultation with the Veterinary Medicines Directorate, introduced a new feed approval mark to help owners identify feeds suitable for horses and ponies prone to equine gastric ulcer syndrome (EGUS).
Currently six feeds in the UK carry the BETA Equine Gastric Ulceration Syndrome (EGUS) Certification Mark including Winergy Equilibrium Growth and Spillers Alfalfa Pro Fibre.
The first, carried out by Nanna Luthersson and colleagues and published online in the Journal of Equine Veterinary Science in March, evaluated the laminitis risk factors in a group of Danish horses and ponies.1 It confirmed that Cold-blooded type animals <149cm, such as certain native ponies, as well as those being kept on high quality pasture were at an increased risk of developing laminitis for the first time. It also highlighted the important role that a change in grass intake, in terms of both type and amount, may play at any time of the year not only the spring as commonly thought.
The second study, funded in part by the PetPlan Charitable Trust, British Veterinary Association Animal Welfare Foundation Norman Hayward Fund and the Laminitis Trust, was undertaken in conjunction with Nicola Menzies-Gow (Royal Veterinary College) and published online in the Equine Veterinary Journal (EVJ) in August. The study evaluated the risk factors for the development of laminitis prior to the occurrence of the disease.2 It identified that low concentrations of the adipose tissue derived hormone adiponectin, together with high serum insulin concentrations (at rest and as part of a diagnostic test for PPID) may predict an increased risk of future pasture-associated laminitis.
It is hoped that future studies will be able to generate more robust cut off values, which will more accurately predict future laminitis development in an individual animal.
The RVC in collaboration with Waltham is now taking this forward through a study in which these markers are measured regularly, in conjunction with a detailed management assessment, in a group of ponies with no known history of laminitis at the start.
Clare Barfoot RNutr and the research and development manager at Spillers said: "The Danish study gives us important practical facts about the susceptibility of cold-blooded types, and is particularly applicable to natives in the UK. The second study gives hope that there may soon be a test or series of tests that will help predict those at an increased risk of suffering from pasture associated laminitis in the future thereby reducing the number of animals affected by this debilitating condition. In the meantime until we fully understand the condition it is sensible to manage all the risk factors we currently know about, in particular keeping your horse at a healthy weight."
References
The Waltham Equine Studies Group has published new research which highlights the effectiveness of grazing muzzles as a tool to help with weight management in ponies.
The research, which was conducted in collaboration with Dr Annette Longland of Equine and Livestock Nutrition Services (ELNS) in Wales2, also showed that longer grass can be more difficult for muzzled ponies to graze, and can cause frustration-related behaviour in some individuals.
According to Waltham, grazing muzzles have already been shown to reduce the pasture intake of ponies by around 80% by significantly reducing bite size and intake.1 Ponies fitted with grazing muzzles may spend more time engaging in foraging and eating than their non-muzzled counterparts, yet the majority either lose weight or retain their body condition. This in turn helps reduce susceptibility to obesity and related disorders, such as insulin dysregulation and laminitis.
Four mature ponies were selected for the study. Their dry matter (DM) and water-soluble carbohydrate (WSC) intakes were measured in spring, summer, and autumn pastures on four, three-hour occasions per pony per season when fitted with or without a grazing muzzle. In addition ponies, with and without muzzles, were allowed to take 10 bites of swards maintained at different heights.
When wearing grazing muzzles pasture intake was reduced by 77% during spring and summer and by 83% during the autumn. Without muzzles the ponies generally reduced the sward length by half with the first bite but when muzzled the reduction was variable and the ponies appeared to experience greater difficulty in accessing the longer versus the shorter swards.
The short (less than 10cm), upright, grass appeared to be the easiest to eat, as leaf blades and stems protruded through the holes in the muzzle. The medium and long swards proved more difficult. They bent under the pressure of the muzzle and became flattened, causing the ponies to adopt various strategies to access the grass. In some cases they pawed the ground to unearth the sward and access it through the muzzle. Alternatively they rammed the solid base of the muzzle hard onto the grass, causing it to buckle and make some blades or stems accessible. These were then yanked vigorously often causing the entire plant to be uprooted and eaten.
Water soluble carbohydrate levels in the sward were similar across the seasons although they were slightly higher in autumn. However, once muzzled the ponies’ intake of WSC wasn’t significantly different across the seasons; strengthening the evidence that the use of grazing muzzles is effective.
Clare Barfoot RNutr and the research and development manager at Spillers said: "While the frustration displayed when the muzzled ponies were on longer grass swards indicates that care should be taken to provide an accessible grass length, grazing muzzles remain an effective weight management tool. They allow turnout over large areas, increasing exercise and allow slow “trickle” feeding, to control weight gain and reduce the risk of obesity-related disorders, without significantly compromising the natural behaviour and wellbeing."
Waltham says grazing muzzles must be used with care, should be properly fitted and horses and ponies should be adapted gradually to wearing them. Group and individual behaviour should be monitored closely to observe any potential concerns caused by changes to the herd dynamics. Ensure that muzzled ponies are confident in drinking and eating through their muzzles before turning them out for prolonged periods. Muzzles must not be used continuously (not more than 10 hours per day) and total exclusion muzzles are not advised. Regular weight monitoring is recommended as some individuals can still gain weight when muzzled.
The Waltham Equine Studies Group has announced the results of two pieces of research designed to improve understanding of the best nutritional support for older horses, whether they are healthy or diagnosed with Pituitary Pars Intermedia Dysfunction (PPID or Cushing's).
The first study: A comparison of nutrient digestibility between adult and aged horses, conducted by the Department of Large Animal clinical Sciences and Animal Science, Michigan State University and The Waltham Equine Studies Group, confirmed (in contrast to earlier work) that there was no difference in digestibility between healthy adult and aged horses when fed a variety of common equine diets.1
In the second study: Characterisation of the faecal bacterial community in adult and elderly horses fed a high fibre high oil or high starch diet, the Institute of Biological Environmental and Rural Sciences, Aberystwyth University, The Waltham Equine Studies Group and Michigan State University used the same horses as the previous study but this time looked at their gut microflora. The results showed that although no significant differences in individual species of bacteria were found, ageing was, however, associated with a reduction in bacterial diversity. This, say the authors, may in part explain why older animals can be at increased risk of intestinal disturbances.2
An abstract that summarised part of the Waltham Equine Studies Group's work on the effect of additional supplementation on aged horses with and without PPID was presented at the 2nd Dorothy Havermeyer Geriatric Workshop in the USA last November.3 This work, carried out in conjunction with Dr Amanda Adams at the University of Kentucky showed that age is key in influencing inflammation and metabolism rather than whether the horse is PPID positive or not.
Professor Pat Harris, head of the Waltham Equine Studies Group, said: "For the parameters we monitored, the research showed that it is being old that is the issue, rather than having PPID."
Clare Barfoot RNutr and the research and development manager at Spillers said: “This should give us a better understanding of the effects of diet and age on metabolism in order to determine optimal nutrition for the senior horse. Preliminary work suggests that this new research may change the way we think of feeding the older horse. Waltham’s work continues to ensure that Spillers feeds remain at the forefront of equine nutrition, for the better health of horses everywhere.”