Models of alimentary dehydration and hyperhydration in a physiological experiment

Models of alimentary dehydration and hyperhydration have been used in physiological experiments for a long time and actively. They represent contrast influences on the water-salt homeostatic system. The model of alimentary dehydration consists of limiting animals’ access to water (water deprivation). The model of alimentary hyperhydration consists of keeping animals without access to food, while instead of water the 4% sucrose solution is offered to animals ad libitum. However, it would be interesting to consider how the physiological indicators, by which the physiological status of animal is usually assessed, change in animals exposed to such influences. This review examines the information available in the literature on such characteristics of the animal’s physiological status as body weight, physical activity, levels of “stress hormones” (corticosterone and (or) cortisol), the reaction of the sympatho-adrenal system, changes in water-salt balance during alimentary de- and hyperhydration of various duration. These data should help researchers to choose an experimental tactic, in particular the duration of water deprivation or hyperhydration, when using such models, taking into account the genetic and ecological characteristics of the animals, as well as the conditions in which they will be kept.