The lsraeli Joumal of Aquaculture - Bamidgeh 49(4), 1997, 199-204

THE EFFECT OF FEED TYPES ON SURVIVAL AND TRYPSIN ACTIVITY
IN TEMORA LONGICORNIS (CRUSTACEA:COPEPODA)


Metin Kumlu

Faculty of Fisheries, University, Çukurova, 01330 Balcali, Adana, Türkyie.
Fax: 90 (322) 3386439

(Received 29.3.97. Accepted 17.11.97)

Abstract

In this study, the effects of different diets on the survival and trypsin-like activity of a calanoid copepod Temora longicornis were investigated in the laboratory. The animals were starved or fed live algae (Diet A), a microeneapsulated diet (Diet B), or the microencapsulated diet plus frozen algal cells (Diet C) for 10 days.

The highest survival (69%) was obtained with those fed Diet A, whereas the lowest (11%) with the starved control (p<0.05). At the end of the experiment, animals fed Diet C displayed a significantly better survival (53%) than those fed Diet B (32%; p<0.05). Measurement of trypsin-like activity revealed that the animals adapted their digestive enzymes to live or dead algal cells more rapidly (within 24 h of feeding) than to formulated diet particles (after 5 days of feeding). The animals fed Diet A had the highest trypsin-like activity (p<0.05). Addition of frozen algal cells into the culture (Diet C) induced a significantly high ertrypsin-like activity over Diet B fed animals (p<0.05). It seems that proteolylio enzymes of copepods feeding on artificial or live feeds have similar responses to other planktonie decapod crustaceans feeding at the primary consumer level.


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