Estrategias de alimentación y cultivo de la dorada (sparus aurata). Regulación endocrina y estado inmunopatológico.

Abstract

Aquaculture production of gilthead sea bream has largely increased over the past decade, and research in this sector is being directed towards the improvement of feeding practice. In this scenario, the most suitable approach for culturing fish would be the use of appropriate feeding standards aimed not only to improve economic returns, but also to develop a lasting cohabitation of sustainable aquaculture and a cleaner environment. In this way, available data indicate that the potential benefits of high-energy diets can be compromised in gilthead sea bream by unrestricted feeding. In addition, the growth hormone spurts of summer is concurrent with up-regulation of circulating levels of growth hormone (GH) and insulin-like growth factor-I (IGF-I). This endocrine arrangement provides an integrated signal for growth and perhaps immune status at times of increasing daylength and temperature. Furthermore, there is a direct evidences for the involvement of somatolactin (SL), a new member of GH and prolactin family. This hormone is up-regulated by the increase of ration size, and their rise and fall is a consistent event after the summer repletion of energy reserves. By other side, restricted feeding regime had lower percent mortality, lower prevalence of infection of the most of the detected parasites, less histopathological alterations than those fed under visual satiety, and seemed to be enhanced respiratory burst activity. Finally, molecular characterization of GH receptor in gilthead sea bream, genomic organization of this receptor in sea bream and turbot and season expression were focused.