The influence of flavour on voluntary water intake in horses

The equine athlete is subject to increasing demands on its physiology; more efficient transport means we are able to travel horses for further and longer, as well as competing them in more challenging conditions. As with humans, the industry surrounding maintenance and recovery of athletes is ever growing, with more and more products being developed in order to gain a competitive edge. Prolonged transport can result in dramatic losses in bodyweight and therefore dehydration, caused by excessive sweating and increased faecal output; this can have a dramatic effect on performance, as electrolyte derangements cause a range of issues such as muscle degeneration and impaction colic. In this study, two synthetic variations of flavours, banana and cherry, were selected to be added to water to determine if they encouraged a greater voluntary water intake compared with plain water and might therefore be a mechanism for mitigation of dehydration in horses. Two trials were carried out using Latin square and Randomised Block designs. Trials 1a and 1b used 6 horses and three different concentrations of each flavour with the aim to ascertain the preferred concentration for both flavours. Trial 2 consisted of 12 horses and tested the palatability of the flavours when offered alongside plain water. Each trial consisted of 3 repetitions in order to eliminate bucket location bias. All horses were without water for 1 hour before each trial period and underwent a standardised exercise test before being offered the waters. Trials 1a and 1b showed no preferred concentration for either flavour. There was a tendency, albeit weak for a preference for the medium concentration of banana and weak concentration of cherry thus those concentrations were chosen for Trial 2. The results from Trial 2 showed that plain water was preferred when offered alongside the 2 flavoured waters, average voluntary fluid intake for plain water was 5.33 litres, which was more than double that of the flavoured waters with average intake for banana of 2.07 litres and cherry of 2.19 litres. In summary, adding banana and cherry flavour to water did not encourage an increase in voluntary fluid intake, and as such cannot be used as a method for mitigating dehydration in horses. Further research is required to ascertain if other flavours, are preferred in water, as this could be added to electrolyte solution in order to make them more palatable and so encourage drinking