Use of mixtures of algal and vegetable oils as fish oil replacers in Asian seabass (Lates calcarifer) feeds and their effects on growth, digestive enzymes, immune biomarkers, fatty acid profiles, and expression of genes involved in fatty acid biosynthesis

• Published in: Aquaculture international 2024-06, Vol.32 (3), p.2427-2453
• Main Authors: Rahman, Md. Arefin, Tantikitti, Chutima, Suanyuk, Naraid, U-taynapun, Kittichon, Chirapongsatonkul, Nion, Forster, Ian, Hlongahlee, Bullika
• Format: Article
• Language: English
• Subjects: Algae; Biomarkers; Biomedical and Life Sciences; Biosynthesis; Carcasses; Diet; Enzymatic activity; Enzyme activity; Fatty acids; Feed conversion; Feeding; Feeds; Fish; Fish oils; Food conversion; Freshwater & Marine Ecology; Gene expression; Growth rate; Lates calcarifer; Life Sciences; Lipids; Marine fishes; Marine resources; Nutrient status; Nutrient utilization; Nutrients; Oil; Palm oil; Parameters; Proximate composition; Pyloric caeca; Survival; Tanks; Vegetable oils; Vegetables; Weight; Weight gain; Zoology
• ISSN: 0967-6120; 1573-143X
• DOI: 10.1007/s10499-023-01278-2

An experiment was conducted to assess the potential use of algal oil (AO) and vegetable (soya and palm oil; 1:1) oil (VO) mixtures as replacers for fish oil (FO) in Asian seabass ( Lates calcarifer ) diets. Six iso-nitrogenous (45% crude protein) and iso-lipidic (10% crude lipid) diets were formulated incorporating FO, VOs, and AO at 100:0:0 (T1), 0:0:100 (T2), 50:25:25 (T3), 25:50:25 (T4), 0:50:50 (T5), and 0:75:25 (T6), respectively. Each diet was given to five tanks (100 L with 10 fish in each) of juvenile fish (3.89±0.23 g initial weight) fed to satiation for 8 weeks. At termination, five replicate groups of fish were used for survival rate (SR), final weight, weight gain, consumed feed, feed conversion ratio (FCR), and specific growth rate (SGR) determination. Proximate composition, nutrient utilization, digestive enzyme activities of the pyloric caeca and intestine, and immune parameters were assessed using fish from three replications. A pooled sample consisting of three replicates was used for the determination of fatty acid profile and lipid quality indices. The liver samples from four replicate groups of fish were pooled into two samples and analyzed for Δ6-desaturase and Elovl5 gene expressions. The SR, growth performance, and feed conversion ratio were not significantly different ( p >0.05) among treatments; however, feed consumption was significantly different ( p