Methyl Ketone Production in Juvenile Red-Sided Garter Snakes

The skin lipids of female red-sided garter snakes contain a series of methyl ketones which function as a sexual attractiveness pheromone. The pheromone is likely regulated by oestrogen. As previous studies have focused mainly on adult females, it is unknown whether juvenile garter snakes produce methyl ketones. The current study was designed to determine whether (1) juvenile female garter snakes are physiologically capable of producing methyl ketones and (2) oestrogen initiates or enhances methyl ketone production in juveniles. Snakes were injected with either oestradiol or an oil vehicle, or received no injection. Subsequent chemical analyses of skin lipid samples clearly demonstrated that juveniles were able to produce methyl ketones regardless of treatment. However, we were unable to demonstrate that oestradiol affected methyl ketone production at this stage in the female life cycle.