The effect of changing haylages of differing chemical composition on the equid metabonome

ABSTRACT: Rapid changes between feeds can cause dysbiosis and colic. The metabolic consequences of changing between haylages is currently unknown. Objectives Characterise urinary and faecal metabonomics in ponies transitioned between haylages varying in botanical composition and physiological age and to determine the speed of metabolic adaptation. Study Design: Repeated Latin Square with 8 Welsh Mountain ponies Methods: Ponies fed four haylages in four x 15-day periods; structured three-day changeover old: new 70: 30; 50.50; 30:70; on days 13,14,15. Day 1 was 100% new haylage. Apparent digestibility determined by multivatiate mixed effects model, from total faecal collections on days 10,11,12. Urinary and faecal collections on day 0, 5, 12 and 14. Metabolic profiling using 1H NMR spectroscopy in urine and faeces with PCA and OPLS-DA to identify diet-induced metabolic shifts. Alignment and normalisation (total quotient method) by Mathworks Matlab R2014a.. Results Ponies achieved metabolic adaptation within five days. Metabonomics were functionally stable at mid changeover (day 14) for most haylage changes. Metabolic responses were driven by forage chemical composition rather than haylage category. Physiologically young haylage R1 produced the greatest shifts, including elevated urinary glycine and altered faecal short-chain fatty acid and aromatic amino acid metabolites, reflecting higher protein bioavailability and rapid microbial reconfiguration. Main limitations Ponies were on all forage diets with no complementary feed. Results may not reflect more abrupt changes between haylages or between different forage types. Conclusions. Metabolic adaptation to new haylages occurred within the first 5 days, were shaped by forage composition, and low fibre haylage altered outputs compared with fibrous mature forages. Metabolism was stable during diet mixing. Metabonomics provides a sensitive, non invasive tool and is discriminatory between forages for nutrient availability and hindgut function. Vigilance should be recommended in the first 5 days of introducing a new forage for horses at risk of diet related gastrointestinal disturbance.

INSTRUMENT(S): Nuclear Magnetic Resonance (NMR) -

PROVIDER: MTBLS15865 | MetaboLights | 2026-09-29

REPOSITORIES: MetaboLights