12
Dietary B vitamins supplementation in microdiets for marine fish larvae: Can it bring advantages to performance and bone malformations? Michael Viegas, Jorge Dias, Luís Conceição, SPAROS, Paulo Gavaia, Vincent Laizé, Center of Marine Sciences of Algarve (CCMAR), Universidade do Algarve
Figure 1. Examples of skeletal malformations in Senegalese sole (Solea senegalensis) post-larvae (74 DAH).
The production output and profitability of the aquaculture industry is highly dependent on the rearing of healthy, fast-growing fish larvae and juveniles. Still, marine hatcheries face challenges that are often associated with variable results during larval and juvenile rearing, due to problems such as stress and disease susceptibility, size dispersion, sub-optimal growth and high incidences of skeletal malformations. Skeletal malformations (Fig. 1) are a major concern for marine hatcheries since most skeletal anomalies have their onset during bone development in early larval stages and can affect swimming competence and the
Hatchery Feed & Management Vol 8 Issue 4 2020
capability to compete for food. This reduces growth rates, increases mortality and significantly affects animal welfare. All together, these issues can result in relevant biological and economical losses. A dietary imbalance of certain micronutrients, such as vitamins, is known to impact fish larval ossification, consequently leading to an increase of skeletal anomalies and/or an imbalance in calcification. Also, dietary B-vitamins requirements have been suggested to be higher at larval stages when compared to juvenile and adult stages. Analysis of vitamins in fish eggs and natural live prey supports this assumption. Given the