The relationship among acceleration, metabolism, and tail beat frequency of channel catfish (Ictalurus punctatus) during critical swimming speed tests

Abstract

Accelerometers collect real-time, high-resolution data over extended time periods providing insight into behavior, movement, and physiology of free-swimming animals in captive or natural environments. In aquaculture settings, acceleration can also be used as a proxy for metabolism, providing useful information to inform bioenergetic models and indices of fish welfare. However, defining the acceleration-metabolic relationship for species of interest is a critical first step before information can be applied. Because catfish aquaculture has a large economic impact in the USA, examining the use of acceleration as a proxy for continuous measures of metabolism could prove beneficial. Here, accelerometers were used in channel catfish (Ictalurus punctatus) to examine the relationship between acceleration as measured by overall dynamic body acceleration (ODBA) and metabolism as measured by oxygen consumption (MO2), and how these variables changed with increasing water velocity during critical swimming speed tests. Tail beat frequency was used to validate ODBA measurements. There was a clear relationship between ODBA and water velocity, and metabolism and water velocity, with ODBA increasing 3.2-fold and metabolism increasing 2-fold as water velocity increased. Tail beat frequency also increased 1.5-fold with each increase in water velocity, validating our acceleration results. There was also a clear relationship between ODBA and metabolism, with metabolism increasing 1.1-fold as the ODBA values increased. Results in this study show accelerometers can act as a proxy for metabolic measures in channel catfish and provide the basis for further applications in bioenergetics or operational welfare to benefit the aquaculture industry.