Island Whirl Equine Colic Research Laboratory, Department of Large Animal Clinical Sciences, University of Florida, College of Veterinary Medicine, Gainesville, FL, USA.
Department of Large Animal Medicine, College of Veterinary Medicine, University of Georgia, Athens, GA, USA.
Equine Vet J. 2021 Jan;53(1):117-124. doi: 10.1111/evj.13259. Epub 2020 Mar 30.
Measurements of water consumed by fed healthy horses might not apply to horses that are unwilling or unable to drink or are not fed for any reason.
To examine the effects of feed deprivation on voluntary water consumption compared with fed conditions.
In vivo experiment.
Eight healthy adult Thoroughbred geldings were used in a randomised crossover design so that each horse served as its own control for fed vs feed-deprived conditions. Water intake, bodyweight, physical findings and vital signs were measured during 4 days of feeding and 4 days of feed deprivation. Daily measurements during the trial periods were PCV, TPP, electrolytes, osmolality and triglycerides. Plasma and extracellular fluid volumes were measured in the last 8 hours of the trial periods. Data were analysed with a two-way analysis of variance with repeated measures, and statistical significance was P ≤ .05.
Feed deprivation immediately and persistently reduced water consumption to ~16% of fed values, with laboratory evidence of mild dehydration on day 4.
Changes in total body water and in water and electrolyte excretion or conservation through faeces and urine were not measured.
Feed consumption has a marked effect on water requirements in healthy horses. Because current guidelines for water needs were obtained in the fed state, they might not apply to horses that are denied feed for any reason or have reduced feed intake. This study provides new information on water consumption in horses that should apply to this essential nutrient in health and disease.
对于不愿或无法饮水或因任何原因未进食的马匹，其摄入的水量可能与健康进食的马匹不同。
研究与进食状态相比，禁食对马自发性饮水的影响。
体内实验。
8 匹健康成年纯血种公马采用随机交叉设计，使每匹马都可作为自身对照，进行进食与禁食状态的比较。在 4 天的进食期和 4 天的禁食期内，分别测量水摄入量、体重、体况和生命体征。试验期间，每日测量红细胞压积、总蛋白、电解质、渗透压和甘油三酯。在试验期的最后 8 小时测量血浆和细胞外液容量。采用重复测量双向方差分析进行数据分析，P≤.05 为有统计学意义。
禁食即刻并持续减少水摄入量至进食量的 16%左右，第 4 天出现实验室证实的轻度脱水。
未测量全身总水量以及通过粪便和尿液排泄或保留的水和电解质的变化。
马的摄食量对水的需求有显著影响。由于目前的水需求指南是在进食状态下获得的，因此它们可能不适用于因任何原因禁食或摄食量减少的马。本研究为健康和疾病中马的水消耗提供了新的信息，这些信息应适用于这种必需营养素。
