Effects of ration size on preferred temperature of lake charr Salvelinus namaycush

Michael J. Mac

doi:10.1007/bf00000830

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Effects of ration size on preferred temperature of lake charr Salvelinus namaycush

Michael J. Mac

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Abstract

I tested the effects of different ration sizes on preferred temperatures of yearling lake charr, Salvelinus namaycush , by feeding them for about 2 weeks on one of four rations and then allowing them to thermoregulate in a temporal thermal gradient for 2 to 3 days. Selected temperatures and ration were directly and linearly correlated: the larger the ration, the higher the temperature selected. Mean preferred temperatures at different rations (shown in parentheses as percent of body weight per day) were as follows: 9.2°C (0.3); 10.6°C (0.8); 11.7°C (2.0); and 12.6°C (5.5). While the shift to lower temperature, under restricted ration, would maximize food conversion efficiency, previous growth studies indicate that even lower selected temperature would have been more beneficial.

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Michael J. Mac. 1985. Effects of ration size on preferred temperature of lake charr Salvelinus namaycush. https://doi.org/10.1007/bf00000830

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