A novel water additive increases voluntary water intake in healthy horses

Objective: To determine whether healthy horses would increase their voluntary water intake (VWI) when offered a novel water additive (NWA) compared to plain water (TAP) and water flavored with sweet feed, referred to as sweet tea (ST). Methods: 12 clinically healthy horses, aged 2 to 5 years old, were enrolled in the experimental crossover design. Four horses were assigned to each group for each of the 3 study weeks. The order that the horses were allocated to study groups was randomly assigned. All horses had access to 2 buckets filled to 16 L, one containing plain water (untreated bucket) and one containing TAP, ST, or NWA (study bucket). Bucket volume for both buckets was measured 3 times daily and refreshed at a minimum of once per day. Individual bucket volumes and total VWI (both buckets) were calculated daily. Manure production was documented twice daily. Each study week consisted of a 5-day assessment followed by a 1-week washout period. Results: Horses drank significantly more water per day (52.0 ± 6.7 L) when assigned to the NWA group versus TAP (30.1 ± 6.2 L) and ST (32.0 ± 5.8 L). The number of fecal piles was significantly greater for NWA compared to ST on day 4 (6.8 ± 1.8 compared to 4.8 ± 1.4, respectively). The horses did not experience any adverse effects during the study. Conclusions: Findings demonstrated that horses offered water containing NWA drank significantly more water compared to those offered TAP or ST. Clinical Relevance: Healthy horses presented with NWA had a statistically significant increase in VWI when compared to TAP or ST.