Grant: Discovery Grants Program - Individual

Zebrafish (Danio rerio) are a popular organism used in a variety of scientific disciplines, from basic biology to cancer research. They are also used in many pharmacology and toxicology studies that quantify specific changes in behaviour with tests of stress and anxiety levels. Pharmacological work may be investigating potential drugs to treat anxiety disorders, with findings relevant to treating human conditions. Toxicological work may be investigating the impact of an ecotoxin or ecotoxicant on the ecological fitness of the fish, which has implications for environmental sustainability. Despite their prevalence, we lack a fundamental understanding of exactly how well these tests of anxiety-like behaviour work, what is occurring at a neurological level, as well as the personality type defined as `shy' or `anxious'. Often, the procedures across laboratories are similar, but not identical, which may account for discrepancies between results. The long term objective of my research program is to better understand the cognitive and neural mechanisms responsible for stress and anxiety in zebrafish. This proposal will investigate three objectives: 1) the reliability (determine whether commonly used anxiety tests in zebrafish are equivalent) and validity (identify the relationship between anxiety and locomotion); 2) the consistency of anxiety traits across a fish's lifespan (learn if a highly anxious juvenile fish is always relatively anxious compared to its mates across a lifespan); and 3) the role of genetic traits in anxiety-like behaviour (determine if selective breeding can be used to generate high and low anxiety fish and if so, what find out what has changed in the brains of these fish). The results of these experiments will allow researchers to gain a clearer understanding of anxiety-like behaviour and whether personality type persists throughout a zebrafish's lifespan and over multiple generations. This is critical for proper interpretation of the many past, current, and future studies that examine anxiety-like behaviour in zebrafish using the common tests employed in this research program. This research program also aims to produce reliable `high anxiety' and `low anxiety' zebrafish for a number of research questions related to how extremes of a fish population respond to pharmacological (e.g., drugs in wastewater effluent) and toxicological (e.g., environmental contamination) compounds. We will also investigate the brain differences of high and low anxiety zebrafish to better understand the neurological underpinnings of anxiety-like behaviour in fish.