Abstract

During prolonged periods of starvation, the respiration of copepods decreases to a basal metabolic rate. This is thought to enhance the survival probability by reducing the energy expenditure. The purpose of the present study was to investigate the recovery of the metabolism of Acartia tonsa from starvation. The respiration rate of nonstarved female A. tonsa was 0.95 +/- 0.17 nl O-2 individual(-1) min(-1) (mean S.E.). Starvation reduced the respiration rate to an average of 0.4 nl O-2 individual(-1) min(-1). Within a few hours after reintroduction to food, all starved individuals showed a hunger response in which their respiration rate not only increased to the respiration rate of those feeding constantly but also transiently rose above it. Thus, the maximal respiration rate of the starved individuals was 160% of the nonstarved rate. The duration of the hunger response depended on the duration of the preceding starvation period. The approximate amounts of oxygen respired in excess of the average nonstarved rate was 10 nl O-2 individual(-1) in copepods starved for 12 h, 60 nl O-2 individual(-1) in copepods starved for 24 h, and 150 nl O-2 individual(-1) in copepods starved for 36 h. The augmented respiration rates were probably induced to cover an increased energy demand for a "catch up" biosynthesis of gut cells and digestive enzymes during recovery. (C) 2003 Elsevier Science B.V. All rights reserved.

Keywords

copepod; Acartia tonsa; respiration; starvation; hunger response

Published in

Journal of Experimental Marine Biology and Ecology
2003, Volume: 283, number: 1-2, article number: PII S0022-0981(02)00473-2
Publisher: ELSEVIER

UKÄ Subject classification

Ecology


Publication identifier

DOI: https://doi.org/10.1016/S0022-0981(02)00473-2

Permanent link to this page (URI)

https://res.slu.se/id/publ/120104