How to improve fish robustness through nutritional supplementation in fish larvae

• Autor(a) principal: Dardengo, Gian Marco
• Data de Publicação: 2020
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.1/15220
• topic: Crescimento; Estado antioxidante; Extractos de plantas; Nutrição; Programação metabólica; Domínio/Área Científica::Ciências Naturais::Outras Ciências Naturais

The concept of nutritional programming began to arouse interest around larviculture sector due to the high metabolic plasticity of larvae. At this life stage, specific methabolic pathways of young organisms are more proned to be alterated with effects that may be propagated in the long terms. The aim of the present study was to assess the effect of dietary curcumin as promoter of both gut maturation and antioxidant status of gilthead seabream larvae (Sparus aurata). Curcumin was delivered through microdiet since mouth opening (4 Days After Hatching, DAH) in two levels of supplementation (LOW and HIGH) and the effects were compared with larvae fed on commercial diet (CTRL). Feeding plan consisted of a short period of co-feeding with live preys (rotifers and Artemia nauplii) and inert diet until 24 DAH, when larvae were weaned. Results on survival rate showed that, curcumin did not influence this paramenter. Key performance parameters did not reveal statistical differences between treatments, although a positive trend was detected in larvae fed on LOW curcumin supplementation. Proteolytic enzymes, such as trypsin and chymotrypsin, were positively influenced by curcumin being significantly higher in larvae fed on HIGH curcumin supplementation. Despite this, curcumin did not influence the activity of the remain digestive enzymes analysed (aminopeptidase, amylase, 4C and 18C-like lipases and alkaline phosphatase). Curcumin did not change the larval feeding habits or diet palatability; results revealed that weaning larvae at 24 DAH did not influence their feeding incidence. Overall, antioxidant status biomarkers (TG, TAC, PC and MOS) did not reveal significant differences between treatments. In summary, although results did not prove significant effects of curcumin on most of the parameters under investigation, some positive trends leave open the possibility of further investigations. These future trials may be addressed independently, or in combination, on both, early programming and new dietary additives, to test different curcumin concentrations.