Meeting Abstract
Exposure to crude oil and hypoxia in fishes affects physiological processes and leads to behavioral impairment such as increased anxiety and aggression. The effects of the combination of hypoxia and oil parental exposures on the F1 generation remain poorly understood. We quantified behavioral effects in larval zebrafish offspring of parents exposed to: 1) Control (normoxia, control diet); 2) Hypoxia (~60% air saturation, control diet); 3) Oil (normoxia, oil-loaded diet); and 4) Hypoxia+Oil (~60% air saturation, oil-loaded diet). After exposure, all adults were bred at either 0 or 30 days post exposure (dpe) to determine if transgenerational effects wash in or out over time. Additionally, brain morphology of exposed parents was assessed. Tests of sociability and boldness were performed in clean, normoxic water on F1 larvae 19 days post fertilization. Sociability tests examined swimming speed, distance traveled, and time spent close to conspecifics. Boldness was assessed by introducing a focal fish to a novel object and determining time and distance spent around the object. Adult brains dissected at 0 and 30 days dpe showed differences in lobe volume between treatments. Social behavior such as time spent near conspecifics of F1 larvae from parents exposed to hypoxia, oil, and hypoxia+oil, was decreased up to ~75% compared to control F1 groups. However, time to initially locate conspecifics did not differ. Because the brain plays a vital role in regulating behavior, future and ongoing experiments are aimed at understanding the mechanistic underpinnings of altered behavior, its transgenerational transfer, and fitness consequences.
