Effects of dietary protein and lipid level, and water temperature, on the post-feeding oxygen consumption of Atlantic cod and haddock |
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| Authors: | Juan C Pérez-Casanova Santosh P Lall & A Kurt Gamperl |
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| Institution: | Ocean Sciences Centre, Memorial University of Newfoundland, St John's, NL, Canada;
Institute for Marine Biosciences, National Research Council Canada, Halifax, NS, Canada |
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| Abstract: | Tank respirometry was used to study the interactive effects of protein:lipid level (55%:11% vs. 42%:16%; both diets isoenergetic) and temperature (11, 6 and 2 °C) on the magnitude and duration of specific dynamic action (SDA) in juvenile Atlantic cod and haddock. The protein:lipid level did not affect any measured variable. However, numerous temperature and species effects were observed. For example, although the maximum post-feeding oxygen consumption (30–50% above routine metabolic rate; RMR) and SDA duration (～55–85 h; SDADUR) were not affected by temperature, SDADUR g?1 of food increased from 11 to 2 °C (from ～3 to 12 h g food?1). While absolute SDA (mg O2) decreased by ～60–65% in cod and ～75% in haddock from 11 to 2 °C, due to a concomitant decrease in food consumption from ～2.0% to 0.6% body mass, SDA comprised between 3.3% and 5.2% of the dietary energy content at all temperatures. Finally, RMR at 11 and 2 °C and SDADUR at 2 °C were 25–35% and 25% greater in cod, respectively, as compared with haddock. These results suggest that feeding reduced protein diets at low water temperatures is unlikely to improve the growth of these species. |
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| Keywords: | specific dynamic action temperature diet Atlantic cod haddock |
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