Ovarian steroid glucuronides function as sex pheromones for male zebrafish, <i>Brachydanio rerio</i>

Abstract

Female zebrafish become attractive to male conspecifics by means of a specific sex attractant secreted by the ovaries. This sex attractant consists of steroid glucuronides; most likely a mixture containing oestradiol-17β- and testosterone glucuronide. Anosmic males are not attracted by the female pheromones and fail to court females with ovulated eggs in the abdomen. Male zebrafish thus detect the ovarian sex attractant, which motivates them to start a series of courtship actions, by olfaction.