Les classes danse : fécondité et devenir d’un programme interdisciplinaire de danse au collège

L’entretien est conduit avec une professeure de français qui met en œuvre des projets chorégraphiques avec des élèves de collège depuis 2009. Après l’obtention d’un doctorat en littérature (sur le thème « Danse et Littérature »), cette enseignante commence sa carrière en 2009 au collège Romain Rolland à Clichy-sous-Bois, classé dans le domaine de l’éducation prioritaire (REP). Elle initie d’emblée des projets chorégraphiques en partenariat avec le Centre national de la danse (CND) et le département de la Seine-Saint-Denis. Le projet est reconduit tous les ans entre 2009 et 2018 au collège Romain Rolland, puis, à partir de 2018 au collège La Neustrie à Bouguenais, en Loire-Atlantique. Il associe différents enseignements, non seulement le cours de français, mais aussi les arts plastiques, la musique, l’EPS, et parfois l’histoire. Il comprend l’intervention d’artistes chorégraphiques (ateliers et rencontres), des sorties au spectacle et des présentations publiques.The interview is conducted with a French teacher who coordinates choreographic projects each year with High School pupils. After receiving a doctorate in Literature, she begins her career in Romain Rolland High School in Clichy-sous-Bois (Paris region) and initiates dance projects in partnership with the Centre national de la danse (French National dance center). The project is renewed each year in Clichy-sous-Bois, then in the La Neustrie High School in the West of France (from 2018 until 2021-2022). It involves many subjects and teachers: not only literature but also visual arts, music, sport and history. It implies workshops animated by dancers and performances

Early weaning of seabass larvae, Dicentrarchus labrax: the effect on microbiota, with particular attention to iron supply and exoenzymes

International audienc

Algal addition in sea bass (Dicentrarchus labrax) larvae rearing : effect on digestive enzymes

National audienc

Effect of nature of dietary lipids on European sea bass morphogenesis: implication of retinoid receptors

International audienceThe effect of the nature and form of supply of dietary lipids on larval development was investigated in European sea bass larvae, by considering the expression of several genes involved in morphogenesis. Fish were fed from 7 to 37 d post-hatch with five isoproteic and isolipidic compound diets incorporating different levels of EPA and DHA provided by phospholipid or neutral lipid. Phospholipid fraction containing 1·1 % (PL1 diet) to 2·3 % (PL3 diet) of EPA and DHA sustained good larval growth and survival, with low vertebral and cephalic deformities. Similar levels of EPA and DHA provided by the neutral lipid fraction were teratogenic and lethal. Nevertheless, dietary phospholipids containing high levels of DHA and EPA (PL5 diet) induced cephalic (8·5 %) and vertebral column deformities (35·3 %) adversely affecting fish growth and survival; moreover, a down-regulation of retinoid X receptor α ( RXRα ), retinoic acid receptor α , retinoic acid receptor γ and bone morphogenetic protein-4 genes was also noted in PL5 dietary group at day 16. High levels of dietary PUFA in neutral lipid (NL3 diet) first up-regulated the expression of RXRα at day 16 and then down-regulated most of the studied genes at day 23, leading to skeletal abnormalities and death of the larvae. A moderate level of PUFA in neutral lipids up-regulated genes only at day 16, inducing a lesser negative effect on growth, survival and malformation rate than the NL3 group. These results showed that retinoid pathways can be influenced by dietary lipids leading to skeletal malformation during sea bass larvae development

Moderate hypoxia but not warming conditions at larval stage induces adverse carry-over effects on hypoxia tolerance of European sea bass ( Dicentrarchus labrax ) juveniles

Environmental conditions, to which organisms are exposed during all their life, may cause possible adaptive responses with consequences in their subsequent life-history trajectory. The objective of this study was to investigate whether ecologically relevant combinations of hypoxia (40% and 100% air saturation) and temperature (15° and 20 °C), occurring during the larval period of European sea bass larvae (Dicentrarchus labrax), could have long-lasting impacts on the physiology of resulting juveniles. Hypoxic challenge tests were performed over one year to give an integrative evaluation of physiological performance. We revealed that juvenile performance was negatively impacted by hypoxia but not by the thermal conditions experienced at larval stage. This impact was related to the prevalence of opercular abnormalities. The present study indicates that exposure to a moderate hypoxia event during larval stage may have adverse carry-over effects, which could compromise fitness and population recruitment success

Early exposure to chronic hypoxia induces short- and long-term regulation of hemoglobin gene expression in European sea bass (Dicentrarchus labrax)

WOS:000408631800021International audienceEuropean sea bass (Dicentrarchus labrax) inhabits coastal waters and may be exposed to hypoxia at different life stages, requiring physiological and behavioral adaptation. In the present study, we attempted to determine whether regulation of hemoglobin (Hb) gene expression plays a role in the physiological response to chronic moderate hypoxia in whole larvae and hematopoietic tissues (head kidney and spleen) of juveniles. We also tested the hypothesis that hypoxia exposure at the larval stage could induce a long-term effect on the regulation of Hb gene expression. For this purpose, D. labrax were exposed to a non-lethal hypoxic condition (40% air saturation) at the larval stage from 28 to 50 days post-hatching (dph) and/or at the juvenile stage from 196 to 296 dph. Data obtained from larvae indicate that hypoxia induced a subtype-specific regulation of Hb gene expression, with a significant decrease of MN-Hba3, MN-Hb beta 4 and MN-Hb beta 5 and increase of MN-Hb alpha 2, LA-Hb alpha 1 and LA-Hb beta 1 transcript levels. Hypoxia did not induce regulation of Hb gene expression in juveniles, except in the head kidney for those that experienced hypoxia at the larval stage. The latter exhibited a significant hypoxia-induced stimulation of MN-Hba2, LA-Hba1 and LA-Hb beta 1 gene expression, associated with stimulation of the PHD-3 gene involved in the hypoxia-inducible factor oxygen-sensing pathway. We conclude that subtype-and stage-specific regulation of Hb gene expression plays a role in the physiological response of D. labrax to cope with hypoxia and that early exposure to low oxygen concentration has a long-term effect on this response

Exposure to chronic moderate hypoxia impacts physiological and developmental traits of European sea bass (Dicentrarchus labrax) larvae

Since European sea bass (Dicentrarchus labrax) larvae occurred in coastal and estuarine waters at early life stages, they are likely to be exposed to reduced dissolved oxygen waters at a sensitive developmental stage. However, the effects of hypoxia at larval stage, which depend in part on fish species, remain very poorly documented in European sea bass. In the present study, the impacts of an experimental exposure to a chronic moderate hypoxia (40 % air saturation) between 30 and 38 days post-hatching on the physiological and developmental traits of European sea bass larvae were assessed. This study was based on the investigation of survival and growth rates, parameters related to energy metabolism [Citrate Synthase (CS) and Cytochrome-c Oxidase (COX) activities], and biological indicators of the maturation of digestive function [pancreatic (trypsin, amylase) and intestinal (Alkaline Phosphatase "AP" and Aminopeptidase-N "N-LAP") enzymes activities]. While condition of hypoxia exposure did not induce any significant mortality event, lower growth rate as well as CS/COX activity ratio was observed in the Hypoxia Treatment group. In parallel, intestinal enzyme activities were also lower under hypoxia. Altogether, the present data suggest that sea bass larvae cope with moderate hypoxia by (1) reducing processes that are costly in energy and (2) regulating mitochondria functions in order to respond to energy-demand conditions. Both these effects are associated with a delay in the maturation of the digestive function

Effects of dietary tannin on growth, feed utilization and digestibility, and carcass composition in juvenile European seabass ( Dicentrarchus labrax L.)

Plant-based products in fish diets are valuable protein alternatives to fishmeal for the aquafeed industry. Many plant feed ingredients contain polyphenolic compounds, including tannins, which can have beneficial or adverse effects. The tolerable threshold of ingested tannins is unknown for marine carnivorous fishes. We studied the effects of tannic acid (TA) supplementation to the diet of juvenile European seabass (Dicentrarchus labrax) by measuring growth, feed utilization and digestibility, and carcass composition. We randomly allocated groups of fish (initial mean body weight of 10.2 ± 0.7 g; n = 40 fish per tank) to 12 replicate cylindrical-conical tanks (three per treatment). The fish were assigned to one of four dietary treatments for five weeks: control diet (C) with tannin-free protein sources (mostly fishmeal as the base diet, containing 55.7% dry matter (DM) crude protein, gross energy 22.3 kJ g−1 DM) and three experimental diets supplemented with 10, 20, or 30 g TA kg−1 (called TA1, TA2, and TA3, respectively). Tannin ingestion resulted in significantly decreased cumulative feed intake, growth, feed and protein efficiencies, apparent digestibility coefficients, hepatosomatic index, and carcass lipids. The protein digestibility in fish fed the 10 g kg−1 tannin-containing diet was significantly lower than that in fish fed the control diet. This threshold should be taken into account when using novel terrestrial and aquatic plant ingredients for temperate marine fishes

Metabolic response to hypoxia in European sea bass (Dicentrarchus labrax) displays developmental plasticity

WOS:000417657800001International audienceSeveral physiological functions in fish are shaped by environmental stimuli received during early life. In particular, early-life hypoxia has been reported to have long-lasting effects on fish metabolism, with potential consequences for fish life history traits. In the present study, we examine whether the synergistic stressors hypoxia (40% and 100% air saturation) and temperature (15 degrees and 20 degrees C), encountered during early life, could condition later metabolic response in European sea bass (Dicentrarchus labrax) juveniles. Growth rate and metabolic parameters related to carbohydrate and lipid metabolism in the liver were investigated at the juvenile stage under normoxic and chronic hypoxic conditions. Juvenile growth rates were significantly lower (p \textless 1 x 10(-6)) under hypoxic conditions and were not improved by prior early-life exposure to hypoxia. Growth was 1.3 times higher (p \textless 5 x 10(-3)) in juveniles reared at 15 degrees C during the larval stage than those reared at 20 degrees C, suggesting that compensatory growth had occurred. Early-life exposure to hypoxia induced higher (p \textless 2 x 10(-6)) glycogen stores in juveniles even though there was no apparent regulation of their carbohydrate metabolism. In the liver of juveniles exposed to chronic hypoxia, lower glycogen content combined with stimulation of phosphoenolpyruvate carboxykinase gene expression and higher lactate concentration indicated a stimulation of the anaerobic glycolytic pathway. Furthermore, hypoxia only induced lower (p \textless 1 x 10(-3)) lipid content in the liver of juveniles that had experienced 15 degrees C at the larval stage. The present study provides evidence that environmental conditions experienced during early life shape the metabolic traits of D. labrax with potential consequences for juvenile physiological performance