Stuck in a Bucket: The Effect of Confinement Stress on Cortisol Levels in Brook Trout (Salvelinus fontinalis)
Additional Funding Sources
This project was made possible by the NSF Idaho EPSCoR Program and by the National Science Foundation under Award No. OIA-1757324.
Abstract
In vertebrates, a primary physiological stress response is characterized by a rapid increase in circulating glucocorticoid levels. Repeated exposure to external stressors can have an impact on overall health, such as metabolism, growth, and immunity. Salmonids are a cold-water fish found in higher elevations; they are important both environmentally and recreationally. Brook Trout, Salvelinus fontinalis, prefer open, clean environments but are often exposed to stressful confinement in hatcheries. The goal of this study is to examine the primary stress response that fish experience during confinement. We investigated the effect of physical and visual stressors on cortisol levels in fingerling brook trout. Wild-caught fish were acclimated in a lab for 6 months. On the day of the experiment, we compared two different routes by which systemic cortisol levels could be collected: water-borne and plasma. On the day of the experiment, fish were held in a smaller confined bucket for one of the following time periods: 3, 5, 15, 30, or 60 mins and then a blood sample was obtained. Steroid samples will be extracted from both water and plasma through solid phase extraction using C18 columns and a vacuum manifold, and measured using an enzymeimmunoassay. We predict a steady increase in cortisol levels over the five-time points. These data will be important to determine the time frame of the stress response resulting from confinement stress and help assess other negative effects of chronic stress in salmonids.
Stuck in a Bucket: The Effect of Confinement Stress on Cortisol Levels in Brook Trout (Salvelinus fontinalis)
In vertebrates, a primary physiological stress response is characterized by a rapid increase in circulating glucocorticoid levels. Repeated exposure to external stressors can have an impact on overall health, such as metabolism, growth, and immunity. Salmonids are a cold-water fish found in higher elevations; they are important both environmentally and recreationally. Brook Trout, Salvelinus fontinalis, prefer open, clean environments but are often exposed to stressful confinement in hatcheries. The goal of this study is to examine the primary stress response that fish experience during confinement. We investigated the effect of physical and visual stressors on cortisol levels in fingerling brook trout. Wild-caught fish were acclimated in a lab for 6 months. On the day of the experiment, we compared two different routes by which systemic cortisol levels could be collected: water-borne and plasma. On the day of the experiment, fish were held in a smaller confined bucket for one of the following time periods: 3, 5, 15, 30, or 60 mins and then a blood sample was obtained. Steroid samples will be extracted from both water and plasma through solid phase extraction using C18 columns and a vacuum manifold, and measured using an enzymeimmunoassay. We predict a steady increase in cortisol levels over the five-time points. These data will be important to determine the time frame of the stress response resulting from confinement stress and help assess other negative effects of chronic stress in salmonids.