Vasopressin receptor 1a, oxytocin receptor, and oxytocin knockout male and female mice display normal perceptual abilities towards non-social odorants.

Genetic knockouts of the vasopressin receptor 1a (Avpr1a), oxytocin receptor (Oxtr), or oxytocin (Oxt) gene in mice have helped cement the causal relationship between these neuropeptide systems and various social behaviors (e.g., social investigation, recognition, and communication, as well as territoriality and aggression).