Digestive enzymes of copepodids and adults of Calanus finmarchicus and C. helgolandicus in relation to particulate matter

• Main Author: Hirche, H.-J.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Institut für Meereskunde 1981
• Subjects: Calanus finmarchicus
• Online Access: https://oceanrep.geomar.de/id/eprint/56116/; https://oceanrep.geomar.de/id/eprint/56116/1/Hirche_HJ_1981.pdf

During spring and in summer the digestive enzymes trypsin and amylase of copepodids and adults of Calanus finmarchicus and C. helgolandicus were studied in a Swedish fjord in relation to various parameters of particulate matter. Regulation mechanisms of digestive enzymes varied with stage of development and physiological condition. In the stages studied three types of regulation were found: In copepodid stages Cl/II trypsin remained constant at a rather high activity irrespective of variations in amylase activity; in CIII-CV and males trypsin and amylase were strongly correlated; in females both enzymes varied independently of each other. Digestive enzymes of CV, females and males of the overwintering generation, were generally very low and did not correlate with any of the food parameters. The digestive enzyme activities were compared with concentrations of chlorophyll a, particulate carbon, nitrogen and carbohydrates at different depths. Amylase of stages CI-CV and adult males and trypsin of CIII-CV and males correlated significantly with carbohydrate concentrations. On the other hand amylase of adult females gave significant correlations with chlorophyll a and carbon. It is suggested that this difference between females and the other stages indicates different food selection.