Please use this identifier to cite or link to this item:
Scopus Web of Science® Altmetric
Type: Journal article
Title: Dietary alpha-linolenic acid does not enhance accumulation of omega-3 long-chain polyunsaturated fatty acids in barramundi (Lates calcarifer)
Author: Tu, W.
Muhlhausler, B.
James, M.
Stone, D.
Gibson, R.
Citation: Comparative Biochemistry and Physiology B- Biochemistry and Molecular Biology, 2013; 164(1):29-37
Publisher: Elsevier Inc.
Issue Date: 2013
ISSN: 1096-4959
Statement of
Wei-Chun Tu, Beverly S. Mühlhäusler, Michael J. James, David A.J. Stone, Robert A. Gibson
Abstract: This study examined the effects of substituting fish oil and fish meal with a blend of alpha-linolenic acid (ALA, 18:3 n-3) rich vegetable oils (14%, w/w) and defatted poultry meal (34%, w/w) in a formulated diet, on growth and tissue fatty acid profiles in barramundi fingerlings. Results indicated that on average, while the ALA levels of the barramundi liver and fillet increased with increasing dietary ALA, there was no corresponding increase in the levels of the omega-3 (n-3) long chain polyunsaturated fatty acid (LCPUFA). Compared to fish consuming a commercial feed, which contained fish meal and fish oil, fish on the ALA diets grew slower, had a lower feed intake and lower n-3 LCPUFA levels in the tissues. Hepatic mRNA expression of Δ6 desaturase (FADS2) and elongase (ELOVL5/2) was ~10 fold and ~3 fold higher, respectively, in all the ALA dietary groups, relative to those fed the commercial feed. However, the level of expression of the two genes was not different between fish fed differing ALA levels. These data demonstrate that increasing the ALA level of the diet is not an appropriate strategy for replacing marine sources of n-3 LCPUFA in barramundi. It was also noted, however, that within the different ALA dietary groups there was a large amount of variation between individual fish in their tissue DHA levels, suggesting a significant heterogeneity in their capacity for conversion of ALA and/or retention of n-3 LCPUFA. When dietary ALA intakes were greater than 0.8% en, tissue DHA levels were inversely related to ALA intake, suggesting that high intake of dietary ALA may inhibit DHA synthesis.
Keywords: Alpha-linolenic acid (ALA18:3 n − 3); Desaturase (FADS); Elongase (ELOVL); Long chain polyunsaturated fatty acid (LCPUFA); Aquaculture nutrition
Rights: © 2012 Elsevier Inc. All rights reserved.
RMID: 0020123631
DOI: 10.1016/j.cbpb.2012.10.001
Appears in Collections:Agriculture, Food and Wine publications

Files in This Item:
File Description SizeFormat 
hdl_79054.pdfSubmitted version749.86 kBAdobe PDFView/Open

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.