Ontogenetic shift in the energy allocation strategy and physiological condition of larval plaice (Pleuronectes platessa)

Type Article
Date 2019-09
Language English
Author(s) Di Pane Julien1, Joly Lea1, Koubbi Philippe2, Giraldo Carolina1, Monchy Sébastien3, Tavernier Eric3, Marchal Paul1, Loots Christophe1
Affiliation(s) 1 : IFREMER, Channel and North Sea Fisheries Research Unit, Boulogne-sur-Mer, France
2 : UFR 918 « Terre, Environnement, Biodiversite´ », Sorbonne Universite´ , Paris, France
3 : LOG—Laboratoire d’Oce´anologie et Ge´osciences, Wimereux, France
Source Plos One (1932-6203) (Public Library of Science (PLoS)), 2019-09 , Vol. 14 , N. 9 , P. e0222261 (17p.)
DOI 10.1371/journal.pone.0222261
WOS© Times Cited 2
Abstract

Condition indices aim to evaluate the physiological status of fish larvae by estimating both the level of starvation and potential of survival. Histological indices reveal direct effects of starvation whereas biochemical indices such as lipid classes or RNA:DNA ratios are used as proxies of condition, giving information on the amount of energy reserves and growth rate, respectively. We combined these three indices to evaluate ontogenetic variations of growth performance, lipid dynamics and nutritional condition of plaice larvae caught in the field during winter 2017 in the eastern English Channel and the Southern Bight of the North Sea. RNA:DNA ratios showed that larvae at the beginning of metamorphosis (stage 4) had a lower growth rate than younger individuals (stages 2 and 3). A significant increase in the proportion of triglycerides also occurred at stage 4, indicating energy storage. Histological indices indicated that most of the larvae were in good condition, even younger ones with low lipid reserves. There was, however, an increase in the proportion of healthy individuals over ontogeny, especially with respect to liver vacuoles which were larger and more numerous for stage 4 larvae. Combined together, these condition indices revealed the ontogenetic shift in the energy allocation strategy of plaice larvae. Young larvae (stages 2 and 3) primarily allocate energy towards somatic growth. The decrease in growth performance for stage 4 was not related to poor condition, but linked to a higher proportion of energy stored as lipids. Since the quantity of lipid reserves is particularly important for plaice larvae to withstand starvation during metamorphosis, this could be considered as a second critical period after the one of exogenous feeding for larval survival and recruitment success.

Full Text
File Pages Size Access
Publisher's official version 17 1 MB Open access
Top of the page

How to cite 

Di Pane Julien, Joly Lea, Koubbi Philippe, Giraldo Carolina, Monchy Sébastien, Tavernier Eric, Marchal Paul, Loots Christophe (2019). Ontogenetic shift in the energy allocation strategy and physiological condition of larval plaice (Pleuronectes platessa). Plos One, 14(9), e0222261 (17p.). Publisher's official version : https://doi.org/10.1371/journal.pone.0222261 , Open Access version : https://archimer.ifremer.fr/doc/00514/62610/