Evaluating the Effect of Age and Sex on Zebrafish (Danio rerio) Behavioral Response Towards a Binary Odorant Mixture

Sensory information coming from environments plays a crucial role in mediating animal behavior. An important sensory response for vertebrates is their sense of smell (olfaction) which plays an essential role in responding to environmental cues. Therefore, olfaction-mediated behaviors are crucial for survival as it enables activities such as foraging, avoiding predators, mating and homing. In the popular vertebrate model, the zebrafish (Danio rerio), olfactory information is received when odorants from the aquatic environment interact with the olfactory neurons in the olfactory epithelium (OE). Although these neurons can regenerate, its capacity to do so may decline as the organism ages. Along with this, these effects are seen to a greater degree in males than females. Taking into account the cellular effects from aging and sex on olfaction, it is important to consider the possibility of behavioral change in zebrafish. The aim of this study is to measure how age and sex effects olfactory-mediated behaviors elicited by zebrafish in response to a binary odorant mixture of L-cysteine and L-alanine. Zebrafish behavior will be observed using an avoidance-attraction trough. I predict that as the zebrafish age, a weaker response will be triggered towards the odorant mixture as the olfactory sensitivity may decrease. Along with this, I also predict that the aging-effects on zebrafish behavior will be weaker in males than females. This study will provide a better understanding on the olfactory-mediated behavioral responses that arise from exposure to a binary odorant mixture and how age and sex interplay with the response.