Daily oxygen consumption rhythms of Senegalese sole solea senegalensis (Kaup, 1858) juveniles

Abstract

Senegalese sole is known to be a species with pronounced nocturnal feeding behaviour. However, as for most fish species, there is a lack of knowledge concerning the influence of such biological rhythm on metabolic rate. The aim of this study was to determine whether individual variation in routine and fed metabolic rate was affected by daily light-dark rhythms in juveniles of Senegalese sole. The individual oxygen consumption measurements in Senegalese sole juveniles were determined by flow-through respirometry, at fasted conditions and after the fish were fed a single meal, the meal time started at 0930 h and fish fed ad libitum for 30 min. The measurements were made during 22 h, of which 8 h was in the light and 14 h in the dark, and started immediately after transfer to the respiratory chambers at 1100 h. The results suggest an influence of light-dark cycles in routine metabolism. It was observed that oxygen consumption increased during the dark phase in fasted fish (FAST) but was higher during the light phase in fed fish (FEED). However, when feed is provided during the light phase, juveniles are capable of shifting oxygen consumption rhythms to respond to the energetic demands of digestion and growth. These results suggest that routine metabolism varies according to the species natural habits as Senegalese sole is known to be nocturnal. The findings of this study underline the importance of understanding the biological rhythms of the species under study before metabolic data are interpreted.

New developments and biological insights into the farming of Solea senegalensis reinforcing its aquaculture potential

“…) and a higher metabolic rate during the dark phase (Castanheira et al . ). However, broodstock appeared to habituate to husbandry routines and had the peak of activity during the day from 14:00 to 18:00, which coincided with feeding at 15:00 (Carazo et al .…”

Domestication and Welfare in Farmed Fish

“…Higher SMR of fast growers appears to be related to a greater investment in high-maintenance digestive tissue that supports rapid growth, which appears to compromise active metabolism [48]. Farmed Senegalese sole (Solea senegalensis) born from wild spawners are nevertheless capable of shifting their routine metabolism from naturally nocturnal to diurnal, responding to daylight feeding regimes [49].…”

The determination of standard metabolic rate in fishes

“…one (Wieser & Medgyesy, ), three (Crear & Forteath, ; McKenzie, ; Roche et al , ), five (Lefevre et al , ), six (Cruz‐Neto & Steffensen, ; Schurmann & Steffensen, ) or 10 (Norin & Malte, ; Boldsen et al , ; Svendsen et al , ). Recognizing the potential for aberrant low Ṁ O 2 values, others have used 10% of the values (Herrmann & Enders, ; Rosewarne et al , ), or all Ṁ O 2 values obtained during the quiet part of the daily cycle (Castanheira et al , ), or after a specific time since the beginning of the experiment (Cutts et al , ). Other variants integrate more data by averaging two quiescent periods (Cheng & Farrell, ), or averaging continuous readings into block means and taking the mean value of a given number of the lowest block means (Eliason et al , , ).…”