Schedule-induced polydipsia as a function of percent of body weight in the Mongolian gerbil.

Three male Mongolian gerbils displayed schedule-induced polydipsia on a fixed-time 3-min food reinforcement schedule at 85% body weight (BW). When the gerbils' body weights were gradually increased to ad lib levels, the polydipsia disappeared. When the gerbils were subsequently reduced to 85% BW again, the previous polydipsia levels of water intake were recaptured. These data replicate previous findings with rats, and suggest that schedule-induced polydipsia may be as robust in gerbils and other species, as it is with rats, once the optimal generating conditions are established.