Straw as an Alternative to Grass Forage in Horses-Effects on Post-Prandial Metabolic Profile, Energy Intake, Behaviour and Gastric Ulceration.
Authors: Jansson Anna, Harris Patricia, Davey Sara Larsdotter, Luthersson Nanna, Ragnarsson Sveinn, Ringmark Sara
Journal: Animals : an open access journal from MDPI
Summary
# Editorial Summary Swedish researchers investigated whether wheat straw could safely replace half of the grass forage in equine rations, prompted by earlier field observations suggesting straw was linked to increased gastric ulcer risk. Using a crossover design with six horses, they compared a control diet of 100% grass forage against an iso-energetic test diet comprising 50% grass hay and 50% wheat straw (on a dry matter basis), performing gastroscopy at baseline and day 21 whilst collecting blood samples and recording behaviour throughout. Neither squamous nor glandular gastric ulcer scores differed between diets, contradicting previous field-based concerns; however, horses on the straw diet spent significantly longer eating, consumed less overall energy and showed substantially reduced plasma insulin concentrations (p < 0.0001), with serotonin levels showing a trend towards elevation. For practitioners managing overweight or metabolically compromised horses, this work suggests that good-quality wheat straw can comprise up to 50% of the forage ration without gastric ulceration risk whilst providing the dual benefits of extended chewing time and favourable metabolic responses—though the relatively small sample size warrants cautious interpretation and consideration of individual horse responses, particularly regarding straw quality and hygiene.
Read the full abstract on PubMed
Practical Takeaways
- •Wheat straw of good hygienic quality can safely replace up to 50% of grass forage without increasing gastric ulcer risk, contrary to previous field study findings
- •Straw-based diets extend eating time and reduce caloric intake and insulin response—valuable for managing overweight horses or those prone to metabolic syndrome
- •Straw can be a cost-effective and practical roughage option for horses with lower energy requirements, provided forage quality is maintained
Key Findings
- •Replacing 50% of grass forage with wheat straw did not increase gastric ulcer scores (squamous or glandular) over 21 days
- •Straw diet extended feeding time (p < 0.05) and significantly reduced energy intake and plasma insulin concentrations compared to grass-only diet (p < 0.0001)
- •Plasma serotonin concentrations tended to be higher on straw diet (p = 0.05), suggesting potential behavioural or metabolic benefits
- •Good quality wheat straw can safely comprise up to 50% of forage-only rations and promotes a metabolic profile suited to overweight or easy-keeper horses