Dietary Lipid Sources Influence Fatty Acid Composition in Tissue of Large Yellow Croaker (Larmichthys crocea) by Regulating Triacylglycerol Synthesis and Catabolism at the Transcriptional Level

Abstract

An 8-week feeding trial was conducted to evaluate the effects of dietary lipid sources on growth performance, fatty acid composition, rate-limiting enzyme activities and gene expression related to lipid metabolism in large yellow croaker (Larmichthys crocea). Five iso-nitrogenous and iso-lipidic experimental diets were formulated to contain different lipid sources, such as fish oil (FO), soybean oil (SO), linseed oil (LO), rapeseed oil (RO) and peanut oil (PO), respectively. Triplicate groups of 50 fish (initial weight 13.77±0.07g) were stocked in 15 floating net cages (1.5m×1.5m×2.0m). Fish fed the diets containing RO and LO had lower weight gain and specific growth rates than those fed the FO, SO and PO diets. Survival, feed efficiency, protein efficiency ratio, hepatosomatic index, viscerasomatic index and condition factor were not significantly affected by different dietary lipid sources. Fish fed the diet containing FO had higher lipid content in whole body compared with the other groups, whereas fish fed the SO diet had the lowest muscle lipid content. Fatty acid profiles of muscle and liver reflected the fatty acid composition of the diets. Plasma glucose, triglyceride, and the enzymatic activity of aspartate aminotransferase and alanine aminotransferase were significantly influenced by different dietary lipid sources, while total protein, cholesterol, superoxide dismutase or malondialdehyde in plasma were not affected by the different dietary lipid sources. Fish fed the LO diet had lower adipose triglyceride lipase and fatty acid synthase activities in liver than those fed the diets containing FO and RO, while the LO diet resulted in the highest hepatic carnitine palmitoultransferase-1 activity. Hepatic gene relative expression of adipose triglyceride lipase and carnitine palmitoyltransferase-1 in fish fed PO diet was significantly higher than all other groups, whereas fish fed the SO and LO diets had lower relative expression levels of lipoprotein lipase than the other groups. The highest relative expression levels of fatty acid synthase and acyl-CoA diacylglycerol acyltransferase-2 were observed in the FO group, while the highest relative expression of glucose 6-phosphate dehydrogenase occurred in fish fed the FO and RO diets. In summary, based on the growth performance, FO and SO appear to be suitable lipid sources for large yellow croaker, with the findings of this study also providing a molecular insight into the role of lipid metabolic mechanism in response to different dietary lipid sources.

Effect of different dietary lipid sources on growth performance and nutrient utilization of + Nile tilapia ( Oreochromis niloticus ) fingerlings

“…Results obtained from several studies suggest that there are no significant effects of FO substitution on fish whole body [17,46]. In other reports, there were significant changes in proximate composition in whole body of fish fed different lipids as replacement for FO [29] Moreover, the type of dietary lipid affects body composition of fish [12]. In our study, the different sources of lipids from plants affected the body composition of O. niloticus.…”

“…While the partial replacement of FO with VOs did not affect growth and feed utilization in some fish species [14,37], in other species the total replacement of dietary FO with VOs significantly impacted negatively on growth and fillet quality resulting in growth retardation, abdominal and hepatic fat deposition [22,29]. Studies on Catla catla fingerlings [38], Rohu carp Labeo rohita [39], sea bass Dicentrachus babrax [5], juvenile African catfish Clarias gariepinus [17], largemouth bass Micropterus salmoides [9], Russian sturgeon Acipenser gueldenstaedtii [8] and large yellow croaker [29] showed comparable growth performance of fish fed FO-supplemented diet to fish fed 100% VOs (SO, GO, PO, SFO, poultry fat) or blend of VOs.…”

“…Substantial research on the use of alternative plant oils (PO, LO, and SO) in juvenile hybrid tilapia [21,23]and in juvenile Nile tilapia Oreochromis niloticus fed diets with SFO and cotton seed oil (CSO) mixture [24], SO and GO mixture [25], SO and PO mixture [10], SO [26]; corn oil (CO), LO, beef tallow [17], show comparable result to FO. O. niloticus have been reported to utilize and require more of linoleic acid (n -6 ) series (18:2n -6 and 20:4n -6 ), with normal growth and reproduction, than omega-3 (n -3 ) FA (National Research Council [12,27,28] The n -6 series of unsaturated fatty acids (UFA) are abundant in SO [21;9], LO [18] and GO [29]. While PO is known to contain large quantity of saturated fatty acids, SFA (16:0 and 18: 1n -9 ) and low n -3 /n -6 , which may reduce the nutritional value of PO [30], promising results in terms of growth improvement by dietary PO supplementation have been reported for large yellow croaker Larmichthys crocea [31], African giant catfish Heterobranchus longifilis fingerlings, [20] and hybrid tilapia raised from stocking to marketable size [32], with better growth and feed utilization achieved in fish fed diets supplemented with PO than FO or SO [31].…”

Evaluation of growth and fatty acid profile of Nile tilapia (Oreochromis niloticus) fed with Schizochytrium sp.

“…Several types of research on incorporating essential nutrients in fish feeds is a new way to food enrichment for human consumption. It is known that the body lipid profile of fish can be adjusted according to diet and inclusion of omega‐3 source additives, such as docosahexaenoic acid (DHA) in fish feed, being an alternative to increase the levels of this fatty acid in the body (Ayisi, Zhao, & Rupia, ; Lenihan‐Geels, Bishop, & Ferguson, ; Martins et al, ; Qiu et al, ).…”

Predict the Relationship between Gene and Large Yellow Croaker’s Economic Traits

“…The gene–trait associations were mainly collected from published papers related to the large yellow croaker. The database contained information about the relevant genes, the corresponding traits that have been generated, and the causes for the trait (e.g., genes of PPARa [ 13 ], COX2 [ 15 ], IL-1β [ 16 ] and traits of adipose [ 17 ], defense [ 18 ], and growth [ 19 ], respectively). As a result, 77 gene–trait associations (including 24 large yellow croaker traits and 102 genes) were collected from more than 1000 papers (see Supplementary Materials).…”