Dietary levels of all-transretinol affect retinoid nuclear receptor expression and skeletal development in European sea bass larvae

Abstract

European sea bass larvae were fed different dietary vitamin A levels. Growth, skeletal development and the expression of genes involved in larval morphogenesis were evaluated. From 7 to 42 d post-hatching, larvae were fed five isoproteic and isolipidic compound diets with graded levels of retinyl acetate (RA; RA0, RA10, RA50, RA250 and RA1000, containing 0, 10, 50, 250 and 1000 mg RA/kg DM, respectively), resulting in an incorporation of 12, 13, 31, 62 and 196 mg all-trans retinol/kg DM. Larvae fed extreme levels of RA had weights 19 % and 27 % lower than those of the RA50 group. The RA1000 diet induced a fall in growth with an increase of circulating and storage retinol forms in larvae, revealing hypervitaminosis. High levels of RA affected maturation of the pancreas and intestine. These data indicated that the optimal RA level was close to 31 mg/kg DM. Inappropriate levels of dietary RA resulted in an alteration of head organisation characterised by the abnormal development of the splanchnocranium and neurocranium, and scoliotic fish. Of the larvae fed RA1000, 78·8 % exhibited skeletal abnormalities, whereas the RA50 group presented with 25 % malformations. A linear correlation between vitamin A level and malformation percentage was observed and mainly associated with an upregulation of retinoic acid receptor-g expression in the RA1000 group during the 2 first weeks after hatching. The expression of retinoid X receptor-a decreased during normal larval development when that of the retinoic acid receptors increased. This work highlights the involvement of retinoid pathways in the appearance of dietary-induced skeletal malformations during posthatching development in sea bass.Retinol: European sea bass: Skeletal malformations: Retinoic acid nuclear receptors (RAR, RXR): Growth factors (BMP-4, IGF-1)

Effects of dietary vitamin A on growth, hematology, digestion and lipometabolism of on-growing gibel carp (Carassius auratus gibelio var. CAS III)

“…Since fishes are not able to synthesize vitamin A themselves, they have to obtain it from food. Vitamin A deficiency symptoms have been reported in many fish, including high mortality, poor growth and feed efficiency, anorexia, exophthalmia, abnormal coloration and bone formation, hemorrhage in the anterior eye chamber and at the base of the fins, keratinization of epithelial tissue and increased erythrocyte osmotic fragility (Takeuchi et al, 1998;Halver, 2002;Moren et al, 2004;Villeneuve et al, 2005). Besides, excess symptoms of vitamin A have also been observed in fish, including slow growth, severe necrosis of the caudal fin, skeletal abnormalities, anemia and reduced body fat (Villeneuve et al, 2005;Ørnsrud et al, 2002NRC, 2011).…”

Crecimiento, supervivencia e incidencia de malformaciones oseas en distintos biotipos de Rhamdia quelen durante la larvicultura

“…Los autores consideran que el máximo nivel de la mezcla vitamínica utilizada en ese ensayo concuerda con los niveles medios o normales reportados en la literatura. Similares resultados fueron encontrados por Villeneuve et al (2005) y Hernández et al (2006. Bajo las condiciones experimentales del presente estudio, las larvas del biotipo NE alimentadas con DS adicionada con mezcla vitamínica-mineral al 6% (ver tabla de composición en Hernández et al, 2009), presentaron un elevado número de malformaciones respecto del biotipo AP, e inclusive del mismo biotipo alimentado con AV.…”

“…En los establecimientos piscícolas, un gran número de peces puede presentar alteraciones en el normal desarrollo esquelético durante el período larval manifestando diferentes tipos de malformaciones , a menudo asociadas a los sistemas de cría intensivos o tipo de alimentación (Boglione et al, 2001;Villeneuve et al, 2005;Sfakianakis et al, 2006;Sikorska et al, 2012).…”

“…De todos estos factores, los nutricionales juegan un rol esencial en la aparición de alteraciones esqueléticas durante los primeros estadios de vida (Cahu et al, 2003), viéndose incrementada su incidencia con el uso de microdietas (Kanazawa, 1981;Villeneuve et al, 2005;Sikorska et al, 2012).…”

“…En los últimos años, el uso de microdietas ha permitido evaluar el rol de los distintos factores alimentarios que determinan alteraciones esqueléticas (Engrola et al, 2009), ya que con presas vivas es muy difícil realizar experiencias precisas con determinados nutrientes (Villeneuve et al, 2005). En este sentido, Cahu et al (2003) y Lall & Lewis-McCrea (2007 revisaron el rol de diferentes nutrientes (minerales, vitaminas, lípidos, proteínas y sus interacciones) en la patogénesis de las deformidades esqueléticas.…”