Larval performance and skeletal deformities in farmed gilthead sea bream (Sparus aurata) fed with graded levels of Vitamin A enriched rotifers (Brachionus plicatilis)

Abstract

Several nutritional studies have found a direct effect of several vitamins in chondrogenic and osteogenic development during early life stages of marine fish species. In the present study, the effect of vitamin A (VA) in gilthead sea bream skeletogenesis was evaluated by means of four different dietary regimes (enriched rotifers) containing increasing levels of total VA (75, 109, 188 and 723 ng total VA mg − 1 DW). Dietary treatments were offered to larvae during the rotifer-feeding phase (4-20 days after hatching), while later all groups were fed with Artemia nauplii and weaned onto the same inert diet. Different dietary doses of VA affected gilthead sea bream larval growth, survival, performance (maturation of the digestive system) and quality (incidence of skeletal deformities). Higher levels of dietary VA than those included in the commercial emulsion for rotifer enrichment led to different levels and typologies of skeletal deformities, indicating that gilthead sea bream larvae were very sensitive to small increases in dietary VA. The degree of ossification was affected by the level of VA in enriched rotifers: the higher amount of VA in the diet, the higher number of skeletal pieces ossified (R = 0.585, P = 0.04). Dietary VA affected the normal process of bone formation and skeletogenesis, the skeletal structures mostly affected by high amounts of dietary VA were those from the cranial skeleton (splanchnocranium), vertebral centrums and caudal fin complex. The premaxilla, maxilla and dentary bones were the cranial structures affected by dietary VA levels, resulting in a large incidence of animals with compressed snout. Dietary VA also affected the normal development of the opercular complex, and a dose-response dependant effect was observed in relation to the incidence of specimens with incomplete operculum. Body shape was also affected by the level of dietary VA, increasing the incidence of specimens with lordosis, kyphosis and/or scoliosis with the dose of VA, being the prehaemal and caudal vertebrae the most affected regions of the vertebral column with this kind of abnormalities. The caudal fin complex was the most affected region of the skeleton affected by dietary treatments as seen by the high incidence of skeletal deformities in fish fed different doses of dietary VA. Deformities affected all skeletal elements composing the caudal fin, although the most affected ones were, in order of importance, the epurals, hypurals, parahypural, neural arch and uroneurals. Differences in sensitivity to dietary VA amongst caudal fin skeletal elements might be due to their differential ontogenetic development and differences in the exposure time to VA. An excess of dietary VA also accelerated the intramembranous ossification process of vertebral centrums leading to one or two supranumerary vertebrae, and a high incidence of fused and compressed vertebral centrums. The sensibility of the developing skeletal structures to dietary VA levels should incline us to test lower doses of VA in live preys enrichments during ear...

Development of the Vertebral Column and Caudal Skeleton in Prochilodus lineatus Larvae under Laboratory Conditions

“…This causes a negative effect on fish productivity due to the morphological alterations reached at commercialization stage. Finally, the economic value of the final product decreased (Boglione et al;Fernández et al, 2008). This paper describes, for the first time, the development of the vertebral column and caudal skeleton in sabalo larvae under culture conditions as being similar to that described in other teleostean fishes with some peculiarities that differentiate it from other groups (Hernández et al, 2012).…”

“…Furthermore, this information represented an important contribution to the morphology of P. lineatus and provides the basis for future studies of skeletal malformations associated with larviculture systems and nutrition (Koumoundouros et al, 1999;Kuzir et al, 2009). We also provide relevant results aiming the definition of feeding strategies that may decrease the incidence of bone malformations during specific time-windows, associated with levels of certain nutrients in the diet that affect normal physiological processes during skeletogenesis phase (Fernández et al;Darias et al, 2011 …”

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

“…Las malformaciones inciden negativamente sobre la productividad de los establecimientos de piscicultura (Fernández et al, 2008), observándose crecimiento reducido, aumento de la susceptibilidad a enfermedades y altos porcentajes de mortandad (Boglione et al, 2001;Koumoundouros et al, 2002;Lewis & Lall, 2006). A pesar de ello, muchos peces con alteraciones morfológicas llegan a la etapa de comercialización desmejorando el valor económico del producto (Boglione et al, 2001;Fernández et al, 2008).…”

“…A pesar de ello, muchos peces con alteraciones morfológicas llegan a la etapa de comercialización desmejorando el valor económico del producto (Boglione et al, 2001;Fernández et al, 2008). Así, Lewis & Lall (2006) proponen el examen temprano de las características merísticas involucradas con el número de vértebras o elementos esqueléticos como una herramienta para detectar precozmente las condiciones de cría inadecuadas.…”

“…Uno de los problemas referido al uso de microdietas se encuentra relacionado con la escasa información de los requerimientos nutricionales para una especie determinada y fase de crecimiento (Fernández et al, 2008), resultando en la utilización de raciones desequilibradas, deficientes o inapropiadas (Cahu et al, 2003;Roo et al, 2009Roo et al, , 2010. 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).…”