Nitrate supplementation in thoroughbred racehorses: Addition of beetroot juice to the equine diet and effects on the gut metabolome

Beetroot juice (BJ), a source of nitrate, was added to the diet of thoroughbred racehorses for a four-week period. Analysis of nitrate/nitrite in plasma showed no significant differences between control and dosed groups. SIFT/MS (selected ion-flow tube/mass spectrometry) was used to analyse the faecal metabolome. The levels and types of volatile organic compounds (VOCs) were compared using headspace sampling of faeces from control and beetroot-supplemented equines, However, there were no significant differences apart from raised levels of acetonitrile in samples from the animals dosed with BJ. The conclusion was that racehorses appear not to have nitrate transporters and that addition of BJ to equine diets would not improve performance