External supporting research Gastric health, diet & performance Peer reviewed EXT-S11 ``` :chatgpt-content-reference{index="0"} ### Science hero image ```text Leave blank

Low-Starch Diet, Gastric Disease & Ridden Pain in Sport Horses

A prospective study of nine show-jumping Warmbloods found significant improvements in gastric disease and ridden pain scores after 12 weeks following a change from a high-sugar, high-starch pelleted feed to a cooked, muesli-type low-starch diet.

Original study title

Improvement of gastric disease and ridden horse pain ethogram scores with diet adaptation in sport horses

Equine gastric disease Gastric ulcers Low-starch diet Starch Sport horses Ridden horse pain Horse behavior Performance Equine welfare

Study at a glance

Year 2024

Study type Prospective observational cohort study

Sample 9 horses

Duration 12 weeks

Population Nine actively competing show-jumping Warmbloods from a single professional stable: 4 mares, 3 stallions and 2 geldings, with a mean age of 7 years and mean body weight of approximately 604 kg

Publication Peer-reviewed journal article

EquiNectar tested? No

Peer reviewed Yes

Open access Yes

Relationship External supporting research

89%

Horses with gastric disease at baseline

Show-jumping Warmbloods studied

4 to 1

Median Equine Gastric Disease score

6 to 3

Median Ridden Horse Pain Ethogram score

Research question

What did the researchers want to understand?

Does changing the diet of actively competing sport horses from a high-sugar, high-starch pelleted feed to a lower-starch muesli-type feed influence gastric disease, ridden pain-related behavior and physiological or locomotor responses during exercise?

Researchers

Study authors

Emmanuelle van Erck-Westergren

Equine Sports Medicine Practice

Victor Westergren

Université Libre de Bruxelles

Sandrine Hanne-Poujade

CWD, Lim group

Camille Hébert

CWD, Lim group

Margaux Vernant

Lambey SAS

Sandrine Lambey

Lambey SAS

Félicie Julien

Lambey SAS

Fe ter Woort

Equine Sports Medicine Practice

Violaine Pineau

Equine Sports Medicine Practice

Research organizations

Research institutions

Université Libre de Bruxelles

University
Belgium

CWD, Lim group

Equestrian equipment company
France

Lambey SAS

Equine nutrition company
France

Equine Sports Medicine Practice

Equine veterinary practice
Belgium

Methodology

How the study was conducted

Study design

This was a prospective observational before-and-after cohort study involving nine show-jumping Warmbloods from one professional stable.

The horses were actively training and competing in FEI show-jumping competition.

At baseline, horses were receiving a pelleted concentrate diet containing more than 30% sugar and starch.

Their concentrate feed was changed to a cooked, muesli-type feed containing 11% starch for 12 weeks.

Forage distribution and general management were maintained during the study, with 8 to 12 kg of forage provided in hay nets two to four times daily.

At baseline and after 12 weeks, horses completed a standardized exercise test. Ridden behavior was assessed using the Ridden Horse Pain Ethogram by two blinded observers.

Gastroscopy was performed the following day and gastric lesions were scored blindly.

Clinical examinations, blood analyses and selected exercise and locomotor measurements were also repeated.

There was no separate untreated or unchanged-diet control group.

What was measured

The researchers evaluated gastric health, ridden behavior, physiological responses to exercise and selected locomotor and jumping variables.

Each horse was examined at baseline and again after 12 weeks following the dietary change.

Gastroscopy was performed and gastric lesions were scored by blinded assessors. Squamous gastric disease, glandular gastric disease and total Equine Gastric Disease scores were evaluated.

Horses completed a standardized exercise test using the same rider. The test included a warm-up, incremental canter work and two consecutive courses of seven jumps.

Ridden behavior was assessed from video recordings using the 24-point Ridden Horse Pain Ethogram. Two blinded observers evaluated the recordings.

Exercise measurements included speed, heart rate and blood lactate.

Jumping and locomotor variables were recorded using the iJUMP instrumented saddle and included measures such as approach to the jump, take-off, flight phase, energy expenditure and recovery of balance after landing.

Blood testing included hematology, serum biochemistry and antioxidant-related measurements.

The researchers also examined correlations between gastric disease severity and Ridden Horse Pain Ethogram scores.

Study findings

Key results

• Nine actively competing show-jumping Warmbloods were evaluated at baseline and again after 12 weeks following a dietary change.

• The original pelleted concentrate contained more than 30% sugar and starch.

• The replacement cooked, muesli-type feed contained 11% starch.

• Eight of nine horses, 89%, had gastric disease at baseline.

• Median total Equine Gastric Disease score decreased from 4 at baseline to 1 after 12 weeks, P < 0.01.

• All squamous gastric lesions observed at baseline were healed at the 12-week assessment.

• Equine glandular gastric disease was present in 8 of 9 horses at baseline and 4 of 9 horses after 12 weeks.

• Median Ridden Horse Pain Ethogram score decreased from 6 at baseline to 3 after 12 weeks, P < 0.01.

• Squamous gastric disease, glandular gastric disease and total gastric disease scores were positively correlated with ridden pain scores.

• Total gastric disease showed a strong positive correlation with RHpE score, r = 0.867, P < 0.01.

• Average speed, heart rate and blood lactate during standardized exercise testing did not differ significantly between baseline and 12 weeks.

• Some jumping variables improved, but improvements were specific to individual jumps rather than consistently observed throughout the exercise test.

• No gastric ulcer medication was administered as part of the study intervention.

• The study had no separate control group, and the complete concentrate feed changed, preventing the effects from being attributed specifically to starch reduction alone.

Interpretation

What do the findings mean?

This study found that gastric disease severity and ridden pain-related behavior improved over 12 weeks following a substantial dietary change in nine actively competing show-jumping horses.

At baseline, 8 of 9 horses had gastric disease. Median total Equine Gastric Disease score decreased from 4 to 1 after 12 weeks, while median Ridden Horse Pain Ethogram score decreased from 6 to 3.

All squamous gastric lesions observed at baseline had healed by the 12-week assessment. Glandular disease was present in 8 of 9 horses at baseline and in 4 of 9 horses after 12 weeks.

Gastric disease scores were also positively correlated with ridden pain scores, with the strongest relationship observed between total gastric disease and RHpE score.

These findings support a relationship between gastric health and expression of discomfort during ridden exercise.

However, the study was a small uncontrolled before-and-after observational study. Because the complete feed changed, the results cannot isolate starch reduction from changes in feed processing, texture or other ingredients.

The results therefore provide useful evidence that overall dietary adaptation may influence gastric health and ridden comfort in sport horses, while further controlled studies are needed to establish which components of the dietary change were responsible.

In practice

Why this research matters

The study highlights the potential importance of feeding management when gastric disease, discomfort or changes in ridden behavior are being investigated in sport horses.

Eight of the nine horses had gastric disease at baseline despite being active competition horses considered healthy enough to train and compete.

After 12 weeks following a dietary change from a high-sugar, high-starch pelleted feed to a lower-starch muesli-type feed, gastric disease scores and ridden pain scores both improved significantly.

The findings are particularly relevant to performance horses because gastric discomfort may not always present as an obvious digestive problem. Changes in willingness to work, ridden behavior or apparent discomfort may form part of the clinical picture.

The study also reinforces the importance of looking beyond a single nutrient. The replacement diet differed in starch content, feed structure and several ingredients, so the findings support reviewing the overall ration rather than assuming that one dietary component explains every case.

Persistent changes in behavior, performance or suspected gastric discomfort require veterinary assessment. Gastroscopy remains necessary to diagnose gastric disease rather than attempting to identify ulcers from behavior alone.

Research transparency

Study limitations

The study included only nine horses, resulting in limited statistical power.

All horses were high-level show-jumping Warmbloods from a single professional stable, limiting how confidently the findings can be generalized to other breeds, disciplines and management systems.

There was no separate control group. Each horse was compared with its own baseline measurements before and after the dietary change, so changes over the 12-week period cannot be attributed exclusively to the new diet.

The intervention changed the complete concentrate feed rather than starch alone. The replacement feed differed in starch and sugar content, physical form and ingredients, including alfalfa chaff, prebiotics, probiotics and clay. It is therefore not possible to determine which dietary component or combination of components contributed to the observed improvement.

The study was funded by Lambey SAS, which supplied the tested feed, and three authors were employees of Lambey SAS. Two additional authors worked for the company that supplied the iJUMP saddle.

The study used a proprietary gastric disease scoring system combining aspects of squamous and glandular disease. The authors noted that this approach may have influenced the apparent prevalence of gastric disease.

Baseline squamous disease was relatively mild, with a median ESGD grade of 1, so the clinical relevance of the improvement in squamous scores may be limited.

Equine glandular gastric disease remains incompletely understood, and the authors noted that existing evidence concerning the influence of diet on EGGD is conflicting.

The findings demonstrate changes observed over time in this group of horses but do not establish that a low-starch diet alone caused gastric healing or improvements in ridden behavior.

EquiNectar context

How this research relates to EquiNectar

This research did not test EquiNectar and was conducted independently of Tharos Ltd.

Its relevance to the EquiNectar Science Center lies in the wider relationship between dietary starch, digestive health and the comfort of performance horses.

The study followed nine show-jumping Warmbloods after their concentrate feed was changed from a pelleted diet containing more than 30% sugar and starch to a cooked, muesli-type diet containing 11% starch. After 12 weeks, gastric disease scores and ridden pain ethogram scores were significantly lower.

The study provides independent evidence that dietary composition can be associated with measurable changes in gastric health and ridden behavior in sport horses.

However, the dietary intervention involved more than a reduction in starch. The replacement feed differed in physical form and contained components including alfalfa chaff, prebiotics, probiotics and clay. The study therefore cannot establish that reducing starch alone produced the observed changes.

EquiNectar was not included in either diet, and the study provides no evidence that EquiNectar prevents or treats equine gastric disease.

Tharos / EquiNectar involvement

None. This study was conducted independently of Tharos Ltd and EquiNectar. EquiNectar was not evaluated in the study.

EquiNectar evaluated No

Transparency

Funding & competing interests

Funding statement

Financial support for the study was provided by Lambey SAS.

Competing interests

Félicie Julien, Margaux Vernant and Sandrine Lambey were employees of Lambey SAS, which provided the feed evaluated in the study. Camille Hébert and Sandrine Hanne-Poujade worked for Lim group, which provided the iJUMP saddle used in the study.

Source record

Publication details

Journal

Journal of Veterinary Internal Medicine

Publisher

Wiley Periodicals LLC

Year

2024

Volume

Issue

Pages / article

3297-3308

DOI

10.1111/jvim.17223

PMID

39465968

Species

Horse

Population

Nine actively competing show-jumping Warmbloods from a single professional stable: 4 mares, 3 stallions and 2 geldings, with a mean age of 7 years and mean body weight of approximately 604 kg

Sample

9 horses

Duration

12 weeks

Setting

A single professional show-jumping stable, with horses training and competing in FEI show-jumping competition

License

CC BY-NC-ND 4.0

View original source ↗ Read full text ↗

Recommended citation

Pineau V, ter Woort F, Julien F, Vernant M, Lambey S, Hébert C, Hanne-Poujade S, Westergren V, van Erck-Westergren E. Improvement of gastric disease and ridden horse pain ethogram scores with diet adaptation in sport horses. Journal of Veterinary Internal Medicine. 2024;38(6):3297-3308. doi:10.1111/jvim.17223.

Low-Starch Diet, Gastric Disease & Ridden Pain in Sport Horses

What did the researchers want to understand?

Study authors

Emmanuelle van Erck-Westergren

Victor Westergren

Sandrine Hanne-Poujade

Camille Hébert

Margaux Vernant

Sandrine Lambey

Félicie Julien

Fe ter Woort

Violaine Pineau

Research institutions

Université Libre de Bruxelles

CWD, Lim group

Lambey SAS

Equine Sports Medicine Practice

How the study was conducted

Key results

What do the findings mean?

Why this research matters

Study limitations

How this research relates to EquiNectar

Funding & competing interests

Funding statement

Competing interests

Publication details

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