Effects of Early Embryonic Ethanol Exposure on Adult Zebrafish Social Behavior

The purpose of this thesis was two-fold: 1) to investigate preferences for various aspects of social stimuli in adult zebrafish, and 2) to investigate whether low-dose embryonic alcohol exposure affected how zebrafish responded to these various social stimuli. Control fish were exposed to different behavioral paradigms to measure responses to and preferences for various social and predator stimuli. Both male and female fish were found to prefer all-male shoals to all-female and mixed shoals, and zebrafish were able to reliably discriminate between larger shoals when ratios of 2 vs. 1 were employed. Fish avoided a moving predator image, and an elongated image of a zebrafish, which resembles a predator, and did not display a preference for yellow or red coloured fish images over control images. To test for the effects of embryonic ethanol exposure, zebrafish eggs were submerged in low concentrations of ethanol for a period of 2 hours at 24 hours post-fertilization and were tested during adulthood (4 months old onwards). Control and alcohol-exposed fish were placed in different behavioral paradigms that measured their responses to social and predator stimuli. It was found that zebrafish exposed to low doses of ethanol at 24 hours post-fertilization do not demonstrate robust differences in comparison to non-exposed control fish for any of the behaviors measured. Overall, the findings present zebrafish responses to various social stimuli, and suggest that low-dose ethanol exposure does not robustly affect social responses.Ph.D.2019-07-11 00:00:0