Objective: To compare health, hydration status, and management of stabled pregnant mares provided drinking water continuously or via 1 of 3 intermittent delivery systems.
Animals: 22 Quarter Horse (QH) or QH-crossbred mares and 18 Belgian or Belgian-crossbred mares (study 1); 24 QH or QH-crossbred mares and 18 Belgian or Belgian-crossbred mares (study 2).
Procedure: Stabled horses were provided water continuously or via 1 of 3 intermittent water delivery systems in 2 study periods during a 2-year period. Body temperature, attitude, appetite, water intake, and urine output were recorded daily. Hygiene of each horse and the stable were assessed weekly. Clinical and biochemical measures of hydration were determined 3 times during each study. Clinical measures of hydration included skin turgor, gum moisture, capillary refill time, and fecal consistency. Biochemical measures of hydration included PCV, plasma total protein concentration, serum osmolality, plasma vasopressin concentration, urine specific gravity, and urine osmolality.
Results: All horses remained healthy. Stable hygiene was worse when horses had continuous access to water. Clinical and biochemical measures of hydration did not differ among water delivery systems.
Conclusions and clinical relevance: Various continuous and intermittent water delivery systems provided adequate amounts of water to stabled horses to maintain health and hydration status. Providing intermittent access to water may be preferable on the basis of stable hygiene.