Development of temperature correction equations for bioelectrical impedance analysis models for brook trout Salvelinus fontinalis.

The objective of this study was to establish the relationships between bioelectrical impedance analysis (BIA) measures (resistance and reactance) and temperature and to determine if corrections improve BIA models for brook trout Salvelinus fontinalis when used over a wide range of temperatures. Both resistance and reactance significantly decreased as temperature increased. Application of temperature corrections to BIA models attempting to predict per cent dry mass reduced root-mean-squared error by an average of 32%. Researchers taking BIA measures on fishes in the field where temperature varies will need to correct resistance and reactance to the temperature at which the BIA model was developed for successful predictions of per cent dry mass to be possible. This study presents a clear description of methods that can be used to developed temperature correction equations so that future researchers can use BIA in any field setting and increase the accuracy of BIA-based estimates of per cent dry mass.