Nursing is rewarding for lactating rabbit does

Investigating affective experiences in animals is inherently challenging. However, the conditioned place preference (CPP) paradigm offers a valuable method for inferring internal states. Understanding the neural and hormonal mechanisms underlying emotions in animals is crucial for elucidating the biological basis of human emotions. CPP assesses an animal's preference for an environment associated with a rewarding or aversive stimulus. While extensively used to study drug effects, the CPP paradigm has been less frequently applied to investigate the effects of natural stimuli. Furthermore, most studies using this paradigm have been conducted with rodents. This study utilizes the CPP paradigm to investigate the rewarding properties of nursing in lactating rabbits, a unique mammalian behavior that occurs once daily. We found that nursing induced CPP in the lactating doe, which we interpret as a positive affective state-an event fulfilling a motivational drive that occurs only every 24 hours. The results of this study provide valuable insights into the affective state of this species and the neurobiological basis of motivation and reward in a natural context.