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Abstract

The effects of feeding frequency on the specific dynamic action of the juvenile snakehead were examined. The fish were fed at four different frequencies with the same total meal intakes (4% body mass), and the postprandial oxygen consumption rate and ammonia excretion rate were determined for two days. The durations of oxygen consumption and ammonia excretion significantly increased with increasing feeding frequency. The specific dynamic action coefficient did not significantly change as the feeding frequency increased. The net energy gain of the fish fed 4 meals daily was lower than the fish fed at the other frequencies. No significant change was found for the post feeding ammonia quotient as the feeding frequency increased. The total post feeding ammonia excretion and its ratio to the total nitrogen intake of the fish fed 4 meals daily were higher than those of the fish fed at any other frequency. These results suggest that frequent feedings result in a prolonged digestion process and reduce net energy gain and dietary protein efficiency, and very frequent feedings with smaller meals may be less beneficial for food energy utilization in the sedentary ambush foraging snakehead fish.

Lophiosilurus alexandri, a sedentary bottom fish, adjusts its physiological parameters to survive in hypoxia condition

“…Hypoxia conditions did not alter the plasma cholesterol concentrations of juvenile L. alexandri, compared to the normoxia treatment. This nding differs from other studies that found an increase or decrease in this metabolite in blood of sh also submitted to hypoxia (Bera et al 2017;Kuppitayanant et al 2011), feed restriction (Assis et al 2020;Favero et al 2019) or low water temperature (Costa et al 2016;Favero et al 2019;He et al 2015) and may be related to increased energy consumption (He et al 2015) and decreased synthesis of endogenous cholesterol by sh during stress situations. According to Costa et al (2019), exposure to stressors and the intensity of stress can lead to increased plasma protein concentrations in sh, as the energy need of these animals increases under such conditions.…”

Does air-breathing meet metabolic demands of the juvenile snakehead,Channa argusin multiple conditions

“…It has been reported that the oxygen consumption rate (MO 2 ) of the snakehead in water increases markedly when the temperature increases by Q 10 values ranging from 1.31 to 4.00 (Xie et al, 2017) and increases after both feeding and exhaustive exercise (Wang et al, 2012; He et al, 2015). When the fish is out of the water, the imbalance between oxygen supply and demand may be more significant.…”