The effects of novelty on food consumption in male and female rats

•Hungry rats were fed novel and familiar foods in a familiar or new environment.•On initial exposure rats in a familiar context consumed small amounts of novel food.•On initial exposure rats in a novel context consumed small amounts of both foods.•Males tested in novel context habituated to novel food faster than other groups.•Females tested in novel context ate small amounts of both foods throughout testing. Novelty powerfully impacts feeding behavior and can override homeostatic and hedonic drives, because consumption of a new food could lead to illness or even death. New foods and new feeding environments can decrease or inhibit feeding, but how the two interact and whether there are sex differences has not been determined. The current study examined consumption of a palatable (high sucrose) novel food compared to a familiar food in adult male and female rats that were fed in a familiar or a novel environment. Rats were deprived of food for 20 h prior to each of eight tests. During the first test, male and female rats that were tested in a familiar environment showed robust taste neophobia, as they mainly consumed familiar food. Across repeated tests, these rats increased consumption of the novel food, which indicated that they habituated to the novel taste and developed a preference for the novel food. In contrast, all rats tested in a novel feeding environment ate very little of both foods during the initial test. Across repeated tests, male rats habituated to the novel food faster than females and by the fourth test ate more of the novel than familiar food. In contrast, females showed sustained, suppressed consumption across habituation tests. These results demonstrated robust differences in feeding behavior depending whether rats were fed at home or in a novel feeding environment, and robust sex differences in habituation to eating in a new environment. These findings suggest that novel context has a greater impact on female consumption than male consumption. This difference may be relevant to sex differences in avoidant behaviors in maladaptive circumstances and the development of psychopathology. Therefore, the behavioral profile outlined in this study for consumption under novelty provides an important starting point for investigation of the underlying neural substrates of novelty processing.