Physiological Responses of Yellow Perch to Hypoxia, Air Exposure, and Bleeding

Abstract

AbstractThe North American Yellow Perch Perca flavescens is a promising candidate species for aquaculture. To evaluate potential problems resulting from husbandry practices, we measured changes in the levels of blood glucose, pH, pO2, pCO2, hematocrit, Na+, K+, Ca2+, and Cl− in response to hypoxia, blood withdrawal, and exposure to air at five time intervals over 24 h. Results were examined against resting or baseline values. Hypoxic conditions induced significant decreases in blood pH, pO2, and Na+ concentration and increases in K+, blood glucose, and hematocrit. Bleeding led to significant decreases in blood Na+, Cl−, and hematocrit and a nearly five‐fold increase in blood glucose. Blood pH, pO2, and hematocrit decreased and pCO2, K+, and glucose decreased at 2 h after air exposure, were over‐compensated for at 6 h, and returned slowly to levels near baseline through 24 h; Na+ and Ca2+ concentrations decreased and remained low through 24 h. Further research defining responses to culture practices and correlations with growth rate, disease resistance, and other critical traits in Yellow Perch is warranted. Our findings suggest that commercial production would benefit from adoption of practices that minimize disturbance to cultured Yellow Perch, as well as development of culture stocks more tolerant of culture conditions.