Effects Of Fish Oil Replacement Research Articles

Effects of fish oil replacement by a combination of soybean and palm oil in Asian seabass (Lates calcarifer) diet on growth, fatty acid profile, digestive enzyme activity, immune parameters and salinity challenge

Effects of fish oil replacement by a combination of soybean and palm oil in Asian seabass (Lates calcarifer) diet on growth, fatty acid profile, digestive enzyme activity, immune parameters and salinity challenge

Response of Macrobrachium rosenbergii to Vegetable Oils Replacing Dietary Fish Oil: Insights From Antioxidant Defense.

The study was conducted to evaluate the effects of fish oil replacement by vegetable oils on growth performance, histology, and antioxidant capacity of Macrobrachium rosenbergii. Three isonitrogenous and isoenergetic diets were formulated with different lipid sources included. DFO diet contained 6% fish oil, whereas DSO and DRO diets included 6% soybean oil and rapeseed oil (RO) as alternatives for fish oil, respectively. Prawns were fed thrice daily for 8 weeks. The results showed that prawns in DFO group showed significantly lower final weight, weight gain ratio, and specific growth rate (SGR), but higher feed intake and feed coefficient ratio than those in DSO and DRO groups. In hepatocellular ultrastructure, malformed and atrophic nucleus and higher apoptosis ratio were observed in DFO group. In addition, levels of haemolymph proinflammatory cytokines, activities of anti-superoxide anion, inducible-type NO-synthase (iNOS) and content of nitric oxide, and hepatopancreas NF-κB signal pathway gene expression in DFO group increased markedly compared to those of DSO and DRO groups. The results suggested that vegetable oils, such as soybean oil and RO might be the better lipid sources in diets for Macrobrachium rosenbergii than fish oil, it may be attributed to modified oxidative status induced by NF-κB-NO signal pathway.

Effects of dietary Nannochloropsis sp. powder and lipids on the growth performance and fatty acid composition of larval and postlarval kuruma shrimp, Marsupenaeus japonicus

The current study evaluated the effects of fish oil replacement with eicosapentaenoic acid-enriched single-cell microalgae in the diets of larval and postlarval kuruma shrimp. Experimental diets containing different level of Nannochloropsis sp. powder (10, 40, 70 g/kg) and lipids (2, 8, 10, 14, 35, 58 g/kg) were evaluated. The substitution of fish oil with algal powder significantly improved shrimp growth compared to that in the control group, with the highest final body weight recorded at 70 g/kg in larvae and 40 g/kg in postlarvae. Larvae fed algal lipids with a dry weight percentage in the diet of greater than 10 g/kg showed significantly lower performance than those in the control group. The neutral lipids in the tissue of the postlarvae that had been fed algal lipids had an improved fatty acid profile, as the content of highly unsaturated fatty acids increased compared to that in the other groups. The content of docosahexaenoic acid increased in the tissue, indicating the possible occurrence of the metabolism and accumulation of Nannochloropsis sp. essential fatty acids. Algal powder could replace FO up to 140 g/kg in shrimp diets without compromising growth and FA profiles.

Effects of fish oil replacement with vegetable oil in diet of sterlet sturgeon (Acipenser ruthenus) broodstock on expression of lipid metabolism related genes in eggs

A 7-month feeding trial was conducted before spawning induction in sterlet (Acipenser ruthenus) broodstock (initial weight 990.3 ± 20.05 g). The effects of dietary fish and vegetable oils were investigated on fatty acid profiles in eggs, hematological characteristics, serum lipid indices, and expression of some lipid metabolism and transport-related genes. Three experimental diets with different levels of fish and vegetable oils were formulated as: FO (100% kilka oil), VO (100% rapeseed oil), and FO + VO (50% kilka oil + 50% rapeseed oil). At the end of the feeding trial, egg samples from ovulating females were collected to examine fatty acid profiles and transcriptional mechanisms involved in lipid metabolism and transport. The broodstock physiological condition was assessed using hematological and biochemical indices. Similar to the diets, oleic acid (18:1n-9) was the most predominant monounsaturated fatty acid among all lipid classes in sterlet eggs. Results revealed that the eggs of the broodstock fed VO diet had the highest ratio of DHA/EPA, while the eggs of the broodstock fed FO + VO or FO diet showed higher ratios of EPA/ARA and DHA/ARA. No changes were observed in the levels of lipoproteins, blood lipid indices or hematological parameters in broodstock. This implies that the examined oil sources did not have any adverse effects on fish health during the feeding trial. Feeding different dietary ratios of VO and FO resulted in altered expression of ApoE and PPARα in the eggs, suggesting that lipid metabolism pathways can be influenced by dietary lipid sources. Compared with broodstock fed FO or FO + VO diet, in eggs from the broodstock fed VO diet the expression of ApoE gene was significantly up-regulated and the expression of PPARα was down-regulated. However, the expression of PPARγ was not significantly different among the dietary treatments. Different expression levels of related genes in treatment with various oil sources demonstrate that ApoE, PPARα, and PPARγ play key roles in lipid metabolism, such that they might perform different functions in lipid metabolism and utilization.

The effects of fish oil replacement by vegetable oils on growth performance and fatty acid profile of rainbow trout: Re-feeding with fish oil finishing diet improved the fatty acid composition

The present study aimed to demonstrate the effects of feeding vegetable oil (VO)-based diets and their blends on growth, feed utilization and fatty acid (FA) profile in rainbow trout, Oncorhynchus mykiss. Juveniles were fed five experimental diets in which dietary fish oil (FO diet containing anchovy oil) was totally or partially replaced by cottonseed oil (CSO), canola oil (CO), MIX1 (50% FO, 25% CSO and 25% CO) and MIX2 (50% CSO and 50% CO) in a grow-out period for 12weeks. Afterwards, all fish were switched to a diet containing 100% FO diet for a further 12weeks to determine the progressive recovery of fatty acid (FA) profile of rainbow trout. Results showed that total and/or partial replacement of FO did not negatively affect growth and feed utilization. Feeding VOs significantly reduced body contents of arachidonic acid (ARA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) to a lower degree than their reduction in the diet. Re-feeding with FO-diet for 12weeks led to significant (P<0.05) improvements in highly unsaturated fatty acid (HUFA), with a full recovery in ARA contents of rainbow trout. Finally, FA profile in whole body of MIX1 fed fish had the closest resemblance to that of FO fed fish.

Effects of fish oil replacement by vegetable oil blend on digestive enzymes and tissue histomorphology of European sea bass (Dicentrarchus labrax) juveniles.

The impact of replacing circa 70% fish oil (FO) by a vegetable oil (VO) blend (rapeseed, linseed, palm oils; 20:50:30) in diets for European sea bass juveniles (IBW 96 ± 0.8 g) was evaluated in terms of activities of digestive enzymes (amylase, lipase, alkaline phosphatase, trypsin and total alkaline proteases) in the anterior (AI) and posterior (PI) intestine and tissue morphology (pyloric caeca-PC, AI, PI, distal intestine-DI and liver). For that purpose, fish were fed the experimental diets for 36 days and then liver and intestine were sampled at 2, 6 and 24 h after the last meal. Alkaline protease characterization was also done in AI and PI at 6 h post-feeding. Dietary VO promoted higher alkaline phosphatase activity at 2 h post-feeding in the AI and at all sampling points in the PI. Total alkaline protease activity was higher at 6 h post-feeding in the PI of fish fed the FO diet. Identical number of bands was observed in zymograms of alkaline proteases of fish fed both diets. No alterations in the histomorphology of PC, AI, PI or DI were noticed in fish fed the VO diets, while in the liver a tendency towards increased hepatocyte vacuolization due to lipid accumulation was observed. Overall, and with the exception of a higher intestine alkaline phosphatase activity, 70% FO replacement by a VO blend in diets for European sea bass resulted in no distinctive alterations on the postprandial pattern of digestive enzyme activities and intestine histomorphology.

Effects of fish oil replacement by a vegetable oil blend on digestibility, postprandial serum metabolite profile, lipid and glucose metabolism of European sea bass (Dicentrarchus labrax) juveniles

Effects of fish oil replacement by a vegetable oil blend on digestibility, postprandial serum metabolite profile, lipid and glucose metabolism of European sea bass (<i>Dicentrarchus labrax</i>) juveniles

Saturated Fatty Acids Limit the Effects of Replacing Fish Oil with Soybean Oil with or without Phospholipid Supplementation in Feeds for Juvenile Cobia

AbstractThe high cost and limited availability of fish oil makes plant‐derived lipids attractive for aquafeed manufacturing, but replacing fish oil with these lipids can result in long‐chain polyunsaturated fatty acid (LC‐PUFA) deficiencies. Fatty acid metabolism, specifically the efficiency of LC‐PUFA utilization, may be influenced by the dietary saturated fatty acid (SFA) content versus that of C18 polyunsaturated fatty acids (PUFAs). We assessed the growth and tissue composition of Cobia Rachycentron canadum (55.3 ± 0.2 g initial weight [mean ± SE]; 10 fish/tank, 3 tanks/diet) fed diets (∼49% protein, ∼10% lipid) containing fish oil; 22:6(n‐3)–amended standard, partially hydrogenated, or fully hydrogenated soybean oil; and these same soybean oils supplemented with soybean lecithin for 8 weeks. Although survival (range = 97–100%), final weight (160–189 g), and feed conversion ratio (1.40–1.52) were unaffected by diet, differences were observed in weight gain (185–241%), specific growth rate (1.87–2.19% body weight/d), and feed intake (2.94–3.44% body weight/d). Significant effects of soybean oil type on final weight, weight gain, feed conversion ratio, specific growth rate, and feed intake were noted, with standard soybean oil generally outperforming the other soybean lipids when oil types were pooled across phospholipid supplementation treatments, whereas phospholipid supplementation had no significant effect on any of the performance measures. Differences in dietary fatty acid profile yielded differences in tissue composition. Feeding standard soybean oil resulted in the most greatly modified profiles, whereas the profiles of fish fed fully hydrogenated, completely saturated soybean oil were most similar to those of the fish oil–fed fish. The magnitude of profile change was greatest in the liver and fillet tissues and smallest in the eye and brain tissues. Although further research is necessary to demonstrate whether SFA‐rich lipids can effectively reduce the LC‐PUFA requirements of Cobia, it is clear that SFA‐rich oils offer a strategic advantage in minimizing the effects of fish oil replacement on tissue fatty acid profile.

Effect of diets containing sesame oil on growth and fatty acid composition of rainbow trout (Oncorhynchus mykiss)

Summary The aim of this study was to investigate effects of fish oil replacement by sesame oil in combination with other vegetable oils in diets with regard to growth performance, feed utilization, desaturation and elongation, whole fish and liver fatty acid profiles of juvenile rainbow trout. Sesame oil (SO) used in the feeds was a mixture of linseed (LO), sunflower (SFO) and fish oil (FO), whereas the control diet contained only FO. Duplicate groups of 60 rainbow trout (~7 g) held under similar culture conditions were fed 2% of their body weight per day for 75 days. At the end of feeding trials, there was no difference in feed utilization efficiency or growth performance between the control group and the groups with added sesame oil (P > 0.05). However, viscerosomatic and hepatosomatic index values were significantly higher (P 0.05). Diets with sesame oil increased desaturation and elongation of 18 : 3n-3 towards n-3 HUFA. The conclusion was that the diet addition of sesame oil in combination with other vegetable oils increased the nutritional quality of the whole fish and liver of juvenile rainbow trout, in particular the docosahexaenoic acid (DHA) level. Therefore, sesame oil may be of interest for use in aquaculture.

Effects of dietary fish oil substitution with mixed vegetable oils on growth and fillet fatty acid composition of juvenile Caspian great sturgeon (Huso huso)

The objective of this study was to determine the effects of fish oil replacement with dietary vegetable oils on growth performance, chemical composition and fatty acids profiles in fillets of farmed Caspian great sturgeon juveniles Huso huso (26.97 ± 0.49 g). Five isonitrogenous and isolipidic diets were formulated, containing 10 % of added oil. The diet with 100 % kilka fish oil (Caspian tyulka, Clupeonella caspia) was the control. Fish oil was substituted by 50 % of vegetable oils consisting of an equal share of sunflower and soybean oils (diet A), sunflower and canola oils (diet B) and soybean and canola oils (diet C). In diet D, 100 % of fish oil was replaced with vegetable oil (1:1:1 ratio of sunflower oil, soybean oil and canola oil). Significant differences (P > 0.05) were not detected during 60 days feeding trial in final body weight, weight gain, condition factor, specific growth rate, feed conversion rate, protein efficiency ratio and the chemical composition of fillet (crude protein, crude lipid, moisture and ash). Generally, the fatty acids composition of fish fillets was reflective of the dietary lipid sources. These results indicate the feasibility of substituting fish oils with the mixture of vegetable oils in diets of juvenile H. huso without negative influence on growth providing optimum ratios of n-3/n-6 and n-3/18:1n-9 is met in the diet.

Dietary fish oil replacement with canola oil up-regulates glutathione peroxidase 1 gene expression in yellowtail kingfish (Seriola lalandi)

The marine carnivore yellowtail kingfish (YTK, Seriola lalandi) was fed diets containing 5% residual fish oil (from the dietary fish meal) plus either 20% fish oil (FO), 20% canola oil (CO), 20% poultry oil (PO), 10% fish oil plus 10% canola oil (FO/CO) or 10% fish oil plus 10% poultry oil (FO/PO) and the effects on fish growth and hepatic expression of two glutathione peroxidase (GPx 1 and GPx 4) and two peroxiredoxin (Prx 1 and Prx 4) antioxidant genes were investigated. Partial (50%) replacement of the added dietary fish oil with poultry oil significantly improved fish growth whereas 100% replacement with canola oil significantly depressed fish growth. The fatty acid profiles of the fish fillets generally reflected those of the dietary oils except that there was apparent selective utilization of palmitic acid (16:0) and oleic acid (18:1n-9) and apparent selective retention of eicospentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3). The Prx 1 and 4 genes were expressed at 10- and 100-fold the level of the GPx 4 and 1 genes, respectively, and at one-tenth the level of the highly expressed β-actin reference gene. Dietary fish oil replacement with canola oil significantly up-regulated GPx 1 gene expression and there was a non-significant tendency towards down-regulation of Prx 1 and Prx 4. The results are discussed in terms of the effects of fish oil replacement on the peroxidation index of the diets and the resulting effects on the target antioxidant enzymes.

Effects of dietary replacement of fish oil by conjugated linoleic acid on some meat quality traits of Pacific white shrimp Litopenaeus vannamei

This experiment was conducted to evaluate the effects of fish oil replacement by conjugated linoleic acid (CLA) on body proximate analysis and thiobarbituric acid-reactive substances, fat content, shear force and fatty acid composition in musculature of Pacific white shrimp ( Litopenaeus vannamei). Graded levels of CLA (0%, 0.5%, 1% and 2%) were added to the basic diet of shrimp at the expense of fish oil. Results showed that fat content ( p = 0.036) and shear force ( p = 0.001) in shrimp musculature were enhanced with increasing dietary CLA inclusion. Fish oil replacement by CLA significantly promoted the incorporation of cis-9, trans-11 CLA ( p = 0.0001) and trans-10, cis-12 CLA ( p < 0.0001) into shrimp musculature; moreover, the polyunsaturated fatty acid was elevated ( p = 0.020) and monounsaturated fatty acid was reduced by CLA inclusion ( p = 0.024). It was concluded that replacement of fish oil by CLA could improve some meat quality traits of shrimp and 1% CLA was an appropriate amount.

Effects of fish oil replacement and re-feeding on the bioaccumulation of organochlorine compounds in gilthead sea bream ( Sparus aurata L.) of market size

Organochlorine pesticide residues and polychlorinated biphenyls were determined in raw materials, fish feeds and fillets from fish exposed through the productive cycle (14 months) to experimental diets with different percentages of fish oil replacement with vegetable oils. Detectable amounts of organochlorine compounds were found in raw materials derived from fish sources with none being detected in vegetable ingredients. Fish feeds presented trace concentrations of contaminants at the ng/g level, which varied according to the contribution of the different resources used in their manufacture. Contaminants did not accumulate during the first 11 months of exposure, and low concentrations of organochlorine compounds were found both at the start and at the end of this feeding period. Fillets from fish fed the fish oil diet presented the highest concentrations of organochlorine compounds, with these decreasing in proportion to fish oil replacement. Three months of fish oil re-feeding during the finishing phase only produced significant bioaccumulation over the course of the first month. By optimizing fish meal and fish oil replacement with vegetable oils alternative feeds can contribute to significantly reduce the risk of organochlorine uptake by consumers.

Fish oil replacement in finfish nutrition

AbstractUnsustainable fishing practices have placed a heavy emphasis on aquaculture to meet the global shortfalls in the supply of fish and seafood, which are commonly accepted as the primary source of health‐promoting essential omega‐3 (n‐3 highly unsaturated fatty acids). However, dietary fish oil is required for the production of omega‐3‐rich farmed fish and this commodity, in a vicious circle, is at present derived solely from wild fisheries. Decreasing global availability coupled with the highly variable price of this resource has forced the aquaculture industry to investigate the possibilities of alternative dietary lipid sources. This review attempts to compile all principal information available regarding the effects of fish oil replacement for the diets of farmed finfish, analysing the findings using a comparative approach among different cultured fish species. The review initially focuses on the present situation with regard to the production, availability and main nutritional characteristics of fish oil and the principal alternative lipid sources (such as vegetable oils and animal fats). Following this, the effects of fish oil replacement in finfish nutrition on feed quality, fish performance, feed efficiency, fish lipid metabolism, final eating quality and related economic aspects are presented and discussed.

Partial replacement of fish oil by soybean oil on lipid distribution and liver histology in European sea bass (Dicentrarchus labrax) and rainbow trout (Oncorhynchus mykiss) juveniles

Summary A 12-week feeding trial was conducted to evaluate the effects of fish oil replacement by soybean oil, on lipid distribution and liver histology of two commercially important finfish species: rainbow trout (Oncorhynchus mykiss) and European sea bass (Dicentrarchus labrax). Sea bass (16.2 ± 0.5 g; mean ± SD) and rainbow trout (52.1 ± 0.5 g) juveniles were fed one of three isonitrogenous (500 g kg−1 CP) and isoenergetic (19 kJ g−1) diets, containing 0% (control, diet A), 25% (diet B) and 50% (diet C) soybean oil. At the end of the experiment, lipid deposition was evaluated in muscle, liver and viscera. Cholesterol and triglycerides levels were also determined in plasma. Tissue total, neutral and polar lipid composition (g kg−1 total lipids) showed no significant differences within species, regardless the dietary treatment. The same trend was observed for plasma parameters (P > 0.05). Viscera were the preferential tissue of lipid deposition, with 252–276 and 469–513 g kg−1 total lipid content in trout and sea bass, respectively. Dietary fish oil replacement had no effect on either hepatic lipid droplets accumulation or degree and pattern of vacuolization in the observed liver sections. These data suggest that both sea bass and trout can be fed diets containing up to 50% soybean oil without adverse effects on tissue lipid composition or liver histology.