The effect of food on the respiration rates of Daphnia magna using a flow-through system

• Main Authors: Claire Schmoker, Santiago Hernández-León
• Format: Article
• Language: English
• Published: Consejo Superior de Investigaciones Científicas 2003-09-01
• Series: Scientia Marina
• Subjects: zooplankton; metabolism; feeding
• Online Access: http://scientiamarina.revistas.csic.es/index.php/scientiamarina/article/view/486

Respiration rates and gut fluorescence of the cladoceran Daphnia magna were studied using a flow-through system. This open system has the advantage of introducing food or producing a starvation effect during the course of the experiment. Severe variations in respiratory rates were observed in relation to the presence or absence of food, indicating short-term variability. Organisms kept starved or at low food for a long period (15-20 h) responded to a sudden increase in food by increasing their respiration rates three- to four-fold in parallel with their gut content. A significant relationship between gut fluorescence and respiration rates was observed, suggesting that feeding and the related swimming activity were responsible for the observed metabolic variability.