An-3 PUFA depletion applied to rainbow trout fry (Oncorhynchus mykiss) does not modulate its subsequent lipid bioconversion capacity

Abstract

Nutritional strategies are currently developed to produce farmed fish rich in n-3 long-chain PUFA (LC-PUFA) whilst replacing fish oil by plant-derived oils in aquafeeds. The optimisation of such strategies requires a thorough understanding of fish lipid metabolism and its nutritional modulation. The present study evaluated the fatty acid bioconversion capacity of rainbow trout (Oncorhynchus mykiss) fry previously depleted in n-3 PUFA through a 60-d pre-experimental feeding period with a sunflower oil-based diet (SO) followed by a 36-d experimental period during which fish were fed either a linseed oil-based diet (LO) (this treatment being called SO/LO) or a fish oil-based diet (FO) (this treatment being called SO/FO). These treatments were compared with fish continuously fed on SO, LO or FO for 96 d. At the end of the 36-d experimental period, SO/LO and SO/FO fish recovered >80 % of the n-3 LC-PUFA reported for LO and FO fish, respectively. Fish fed on LO showed high apparent in vivo elongation and desaturation activities along the n-3 biosynthesis pathway. However, at the end of the experimental period, no impact of the fish n-3 PUFA depletion was observed on apparent in vivo elongation and desaturation activities of SO/LO fish as compared with LO fish. In contrast, the fish n-3 PUFA depletion negatively modulated the n-6 PUFA bioconversion capacity of fish in terms of reduced apparent in vivo elongation and desaturation activities. The effects were similar after 10 or 36 d of the experimental period, indicating the absence of short-term effects.

Parental nutritional programming and a reminder during juvenile stage affect growth, lipid metabolism and utilisation in later developmental stages of a marine teleost, the gilthead sea bream (Sparus aurata)

“…Thus, parental nutritional interventions can modulate epigenetic mechanisms that control 'metabolic decisions' that are meiostatically and mitotically stable through life in humans (32) , rodents (33,34) and cattle (35) . In fish, nutritional programming studies have mostly focused on early feeding (36)(37)(38)(39)(40)(41)(42)(43) , whereas parental nutritional interventions are scarcer (44)(45)(46) .…”

Assessment of dietary lipid sources in tropical gar,Atractosteus tropicuslarvae: Growth parameters and intermediary lipogenic gene expression

“…(20: 5n-3; EPA) and docosahexaenoic acid (22: 6n-3; DHA) (Koven et al, 2001;Tocher, 2010) that are known to improve the growth and survival of fish larvae (Escaffre & Kaushik, 1995;Gonçalves & Cyrino, 2014;Kousoulaki, Saether, Albrektsen, & Noble, 2015;Mellery et al, 2017;Miller, Nichols, & Carter, 2007). The challenge for the aquafeed industry is to produce high-quality food using the best nutrients to improve the survival of fish larvae (Norambuena et al, 2013).…”

Dietary Polyunsaturated Fatty Acid Supplementations Could Significantly Promote the Δ6 Fatty Acid Desaturase and Fatty Acid Elongase Gene Expression, Long Chain Polyunsaturated Fatty Acids, and Growth of Juvenile Cobia

“…This is consistent with the previous reports, in which C 18 PUFAs could promote LC‐PUFA biosynthesis by cooperating with transcription factors. High apparent in vivo elongation and desaturation activities along the n‐3 biosynthesis pathway were found in the fish fed linseed oil‐based diet . (3) The supplementation of LNA or LA could promote LC‐PUFA biosynthesis by accelebrating fatty acids to be desaturated and elongated.…”