Effects of dietary arachidonic and eicosapentaenoic acids on common dentex (Dentex dentex Linnaeus 1758) larval performance

Abstract

Oily emulsions containing constant levels of total fatty acids (FAs) and varying eicosapentaenoic acid (EPA) and arachidonic acid (ARA) levels were used to enrich rotifers. Common dentex larval survival and growth were compared between groups fed different enriched live prey. Growth, survival rate, and lipid composition of larvae suggest that feeding common dentex in the first 15 days posthatching with 2.5–3% EPA, 6–8% docosahexaenoic acid (DHA), and DHA/EPA ratio of 2.0–2.5 is sufficient to fulfill their EPA requirements. Higher amounts of dietary EPA did not result in any significant improvement in growth or survival. EPA requirement during this period of larval development does not seem to be as critical as other FAs during the first 15 days of common dentex larval development, but it does not exclude its essentiality later in development. In the case of ARA, nutritional requirements are low compared to other marine finfish species, with the upper limit of this essential FA being around 2% of total FAs provided in the live prey composition.

Trophic Levels Predict the Nutritional Essentiality of Polyunsaturated Fatty Acids in Fish—Introduction to a Special Section and a Brief Synthesis

“…This article is protected by copyright. All rights reserved findings highlighting the essentiality of 20:4n-6 have been reported with Japanese eel Anguilla japonica, European Sea Bass Dicentrarchus labrax, Yellow Catfish Pelteobagrus fulvidraco, common Dentex Dentex dentex, and Cobia (Shahkar et al, 2016;Torrecillas et al, 2017Torrecillas et al, , 2018Ma et al, 2018;Papiol and Estevez 2019;Araujo et al, 2019). Taken together, these studies seem to suggest that 20:5n-3 is, at most, conditionally essential, whereas 20:4n-6 and 22:6n-3 are particularly critical in feeds for these species.…”

“…20:4n-6(Araujo et al, 2019), and 20:4n-6 and 20:5n-3(Norambuena et al, 2016;Salini et al, 2016;Papiol and Estevez 2019), as well as dietary lipid content(Glencross 2009).…”