Effect of nutritive and bulk intake on the suppression of food-deprivation polydipsia in the gerbil.

Gerbils which become polydipsic when food-deprived, were refed with mixtures of Laboratory Chow and a non-nutritive material (Sterolit) after 2 days of food deprivation. Suppression of polydipsia was not related to bulk of material ingested. Instead, when the intake of Chow in the mixture reached 6 g, suppression appeared precipitously suggesting the existence of a threshold for suppression. It was concluded that nutritional, rather than stomach fill, factors were primary in suppressing polydipsia on the refeeding day.