Effects of temperature and fatigue on the metabolism and swimming capacity of juvenile Chinese sturgeon (Acipenser sinensis)

Abstract

Chinese sturgeon (Acipenser sinensis) is a critically endangered species. A flume-type respirometer, with video, was used to conduct two consecutive stepped velocity tests at 10, 15, 20, and 25 °C. Extent of recovery was measured after the 60-min recovery period between trials, and the recovery ratio for critical swimming speed (U ) averaged 91.88% across temperatures. Temperature (T) effects were determined by comparing U, oxygen consumption rate (MO ), and tail beat frequency (TBF) for each temperature. Results from the two trials were compared to determine the effect of exercise. The U occurring at 15 °C in both trials was significantly higher than that at 10 and 25 °C (p < 0.05). The U was plotted as a function of T and curve-fitting allowed calculation of the optimal swimming temperature 3.28 BL/s at 15.96 °C (trial 1) and 2.98 BL/s at 15.85 °C (trial 2). In trial 1, MO increased rapidly with U, but then declined sharply as swimming speed approached U . In trial 2, MO increased more slowly, but continuously, to U . TBF was directly proportional to U and the slope (dTBF/dU) for trial 2 was significantly lower than that for trial 1. The inverse slope (tail beats per body length, TB/BL) is a measure of swimming efficiency and the significant difference in slopes implies that the exercise training provided by trial 1 led to a significant increase in swimming efficiency in trial 2.

Repeat UCrit and endurance swimming in juvenile shortnose sturgeon (Acipenser brevirostrum)

“…As the success rate for migration through and/or over various fish barriers is likely limited by a fish's swimming performance, it is highly plausible that fish, including sturgeon, may require multiple attempts to traverse a fish passage structure (Cai et al ., ; Yuan et al ., ). Shortnose sturgeon, a relatively poor performing fish relative to other fish species, might not show consistent swimming performance patterns if they are forced to undergo multiple fatigue–recovery cycles.…”

“…Cai et al (2014) found that the critical swimming (UCrit) speeds of sturgeon decreased~32% with successive recoveries from fatigue over four cycles (~19-20 C; trials were separated by 20 min). More recently, however, Yuan et al (2017) found that there were no differences in UCrit between swim trials 1 and 2 (separated by 60 min) across temperatures (10-25 C) for Chinese sturgeon. Thus, these differences suggest that the effects of repetitive swimming on the metrics of swimming performance are not clear, at least for sturgeon species, and further research is required.…”

“…It has been shown that swimming ability among fishes can vary with differences in anatomy ( e.g ., tail and fin morphology and position; Webb, ; Blake, ), physiology and behaviour (Kieffer et al ., ; May & Kieffer, ). Most research on swimming performance of fish has been conducted on salmonids, but more recent work has focused on nonsalmonids such as Acipenseridae (sturgeons; Kieffer et al ., ; Verhille et al ., ; Thiem et al ., ; Deslauriers et al ., ; Downie & Kieffer, ; Schumann et al ., ; Cai et al ., ; Yuan et al ., ; Katopodis et al ., ).…”

“…As the success rate for migration through and/or over various fish barriers is likely limited by a fish's swimming performance, it is highly plausible that fish, including sturgeon, may require multiple attempts to traverse a fish passage structure (Cai et al, 2014;Yuan et al, 2017).…”

Effects of temperature on growth, hematology, and immune responses of subadult Chinese sturgeon (Acipenser sinensisGray 1835) under different ammonia nitrogen conditions in recirculating aquaculture system

“…In an RAS, water temperature and ammonia nitrogen are two important environmental factors that affect the growth of the Chinese sturgeon (Du et al, ; Yuan et al, ). It is found that higher water temperatures (up to 20°C) may have beneficial effects in maximizing growth and improving the immunological capacity of juvenile shortnose sturgeon ( Acipenser brevirostrum ) compared with a water temperature of 11°C, regardless of fish size (Gradil et al, ).…”