The suckling pheromone

Mammalian females can stimulate and guide their newborns to their mammae, and newborns respond efficiently with coordinated motions of the head and suckling, but how this behavior is controlled has been unclear. Maternal odors have been suggested to play a role, but the precise identity of the signals has remained elusive. In the July 3 Nature, Benoist Schaal and colleagues from Centre Européen des Sciences du Goût present a complete chemical and behavioral description of a rabbit mammary pheromone that can induce suckling (Nature, 424:68-72, July 3, 2003).

Schaal et al. extracted the volatiles from rabbit milk using a gas chromatograph equipped with a sniffing device that allowed concurrent detection by neonatal rabbits and a flame ionization detector. They observed that one volatile, 2-methylbut-2-enal (2MB2), triggered a considerably greater response in the neonatal rabbits compared with any of the other volatiles and with the solvent alone. In addition,...