Long-chain Polyunsaturated Fatty Acids Content Research Articles

Antioxidant capacity and lipid composition of Brachionus plicatilis and Artemia enriched with a mixture of different post-processing formats of Navicula salinicola and Isochrysis galbana and lipid emulsions

AbstractLive prey used by the aquaculture industry are usually poor in some essential nutrients including long chain polyunsaturated fatty acids (LC-PUFA) and must be enriched to improve their nutritional value prior to larval feeding. Standard enrichment protocols are commonly based on lipid emulsions, being associated to a high oxidative stress condition. The combination of microalgae and lipid emulsion can palliate this situation, where the oxidative stress can be partially compensated by the antioxidant compounds present in microalgae. The maintenance of living microalgae in culture facilities is laborious, and the produced biomass may present fluctuating properties, leading to a serious bottleneck in the cultivation of live prey. Hence, substitutes for live microalgae including pastes or dried formats are receiving increasing research attention due to its nutritional stability, longer shelf-life and easy handling. In this study four different microalgae formats combined with a lipid emulsion are tested as enrichment products for Brachionus plicatilis and Artemia. Thus, fresh, frozen and spray-dried Navicula salinicola (NFRE, NFRO and NSD, respectively), and spray-dried Isochrysis galbana (ISD) were mixed with a commercial oil concentrate (IncromegaTM) or a marine lecithin (LC 60®), and added for 5 h to the rotifer or Artemia culture media. The antioxidant capacity of the microalgae extracts and the live prey activity of antioxidant enzymes, peroxides index (PxI) and thiobarbituric acid reactive substances (TBARS) were evaluated. The lipid profile of microalgae formats and enriched live preys was also determined. Ethyl acetate extract was the most antioxidant active extract of all microalgae formats. In addition, overall, I. galbana seems to be better than any N. salinicola format for a more effective protection against oxidative stress and for live prey lipid enrichment. Both rotifer and Artemia cultured with the mixture of I. galbana and the lipid emulsion generally showed higher DHA/EPA and EPA/ARA ratios. Moreover, the combination of the microalgae with LC 60® lipid emulsion highly favored Artemia´s polar lipid and DHA incorporation. Among microalgae products, both spray-dried formats better enhanced live prey n-3 LC-PUFA content. Our results highlight the great potential of new microalgae-derived products to improve effectiveness of current live prey lipid enrichment protocols used in aquaculture.

Влияние зимовки на морфофизиологические и химические показатели судака Sander lucioperca

During the wintering period, sander from their natural habitat and grown in farm conditions undergo changes in morphophysiological and chemical status due to the expenditure of energy reserves of the body and the redistri-bution of nutrients in the muscles and liver. This is expressed in a significant decrease in the content of ab-dominal fat in the body of wild and factory individuals (by 45 and 16%, respectively), muscle fat content (by 26% in wild individuals) and liver (by 59% in wild and 16% in farm fish), vitamin C in muscles (by 56 and 23%, respectively). At the same time, the content of nitrogen–free extractives in the muscles and liver increases many times – by 47 and 31%, respectively, in wild individuals and by 31 and 29% in sander raised in cages. The proportion of monounsaturated fatty acids in the lipids of sander muscles in winter significantly increases and the proportion of polyunsaturated fatty acids (PUFA) decreases, especially eicosapentaenoic (EPA), docosahexaenoic (DHA) and arachidonic, against the background of an increase in the level of these acids in the liver. From the point of view of meat quality, estimated by the content of long-chain PUFA, during the wintering period there is a significant decrease in the nutritional value 
 of caught and raised fish, which is expressed in a 2-3-fold decrease in EPA + DHA in fillets. Such changes are the adaptation of fish to cold temperature conditions during prolonged wintering and are associated with puberty.

Feeding Strategy to Use Beef Tallow and Modify Farmed Tiger Puffer Fatty Acid Composition.

A 12-week feeding experiment was conducted to evaluate the effects of replacing fish oil (FO) with beef tallow (BT) on the fatty acid composition of farmed tiger puffer (Takifugu rubripes). Two replacement strategies were used: a standard Graded Dietary Replacement of FO with BT (GDR strategy) and Alternate Feeding between FO- and BT-based Diets (AFD strategy). The positive and negative control diets were formulated with 6% FO (FO-C group) or BT (BT-C group) as the sole added lipid source. In the GDR strategy, three experimental diets were formulated, with 25, 50 and 75% of the added FO in the FO-C diet replaced with BT, named 25BT, 50BT and 75BT, respectively. In the AFD strategy, alternated feeding patterns between the FO-C and BT-C diet-namely, 1, 2 and 3 weeks with BT-C followed by 1 week feeding with FO-C (1BT-1FO, 2BT-1FO and 3BT-1FO, respectively)-were applied. Each diet or feeding strategy was assigned to triplicate tanks. The results showed that dietary BT inclusion reduced the contents of long-chain polyunsaturated fatty acids (LC-PUFA) in both the muscle and liver (edible tissues for this species) of the experimental fish, and the liver displayed a more drastic decrease than the muscle. The LC-PUFA content linearly decreased with the decreasing dietary FO levels in the GDR strategy. However, in the AFD strategy, a linear relationship was not observed between the LC-PUFA content and the FO feeding duration. The 3BT-1FO treatment resulted in higher LC-PUFA content than 2BT-1FO. When comparing the two strategies with the same final FO administration level-namely, 50BT vs. 1BT-1FO, and in particular, 75BT vs. 3BT-1FO-the AFD strategy resulted in higher LC-PUFA contents in both the muscle and liver than the GDR strategy. In conclusion, when FO was replaced with BT in the diets, alternate feeding between FO- and BT-based diets resulted in a higher LC-PUFA content than the standard direct replacement. Three weeks of feeding with BT-C followed by one week of feeding with FO-C appeared to be a good alternate feeding pattern. This study provided a promising strategy of FO-sparing in fish farming when the LC-PUFA contents were maintained as high as possible.

Beyond fish oil: Assessing the implications of alternative dietary lipid sources for turbot (Scophthalmus maximus) on growth, nutrient utilization and muscle quality

Various combinations of alternative marine lipid sources were evaluated for their potential to replace commercially available fish oil, specifically sardine oil (SO), in turbot (Scophthalmus maximus). A commercially based diet was used as a control (CTRL) containing sardine oil (7.0%) and rapeseed oil (RO; 3.8%) as the main lipid sources, providing 1.9% EPA + DHA. A positive control (SARDINE) was also included, which used SO as the sole lipid source to provide 2.6% EPA + DHA. Two other diets were formulated to target approximately the same levels of EPA + DHA as the positive control: ALGA (2.7% algae oil, 5.4% SO, and 2.7% RO), and ALGAMIX (a blend of 2.0% micro and macro algae biomass, 9.5% SO, and 0.7% salmon oil, a by-product of the salmon industry). SO was completely replaced in two alternative diets, ALT1 and ALT2, by different ratios of salmon and algae oils: 8.0/2.9 and 6.0/4.9%, providing 2.0% and 2.8% EPA + DHA, respectively. In these alternative diets, 30% of the fish meal was also replaced, by Tenebrio molitor meal and a single-cell protein concentrate from Corynebacterium glutamicum. After 75 days of feeding, all diets were equally well-accepted by the fish, and no significant differences were found in feed efficiency, growth performance, and somatic indexes. All fish had similar muscle EPA + DHA values, but only the ALGAMIX group exceeded the European Food Safety Authority (EFSA) recommended EPA + DHA levels for human daily consumption. Hepatic lipogenesis was decreased in fish fed with higher levels of EPA + DHA, suggesting that increased n-3 LC-PUFA negatively affects lipid metabolism. Additionally, the mixture of algae oil, sardine oil, and rapeseed oil (ALGA diet) showed potential for improving muscle antioxidant capacity. Overall, this study showed that combining expensive sources of n-3 long-chain polyunsaturated fatty acids (LC-PUFA) with less expensive oils, such as salmon by-product oil or vegetable oils, may be a viable cost-efficient strategy for replacing SO in diets for turbot. This can be achieved without compromising growth and while ensuring high flesh n-3 LC-PUFA content and improving its antioxidant potential.

Protective mechanisms of a microbial oil against hypercholesterolemia: evidence from a zebrafish model.

A Western diet elevates the circulating lipoprotein and triglyceride levels which are the major risk factors in cardiovascular disease (CVD) development. Consumption of long-chain omega-3 fatty acids can stall the disease progression. Although these fatty acids can significantly impact the intestine under a hypercholesterolemic condition, the associated changes have not been studied in detail. Therefore, we investigated the alterations in the intestinal transcriptome along with the deviations in the plasma lipids and liver histomorphology of zebrafish offered DHA- and EPA-rich oil. Fish were allocated to 4 dietary treatments: a control group, a high cholesterol group and microbial oil groups with low (3.3%) and high (6.6%) inclusion levels. We quantified the total cholesterol, lipoprotein and triglyceride levels in the plasma. In addition, we assessed the liver histology, intestinal transcriptome and plasma lipidomic profiles of the study groups. The results suggested that higher levels of dietary microbial oil could control the CVD risk factor indices in zebrafish plasma. Furthermore, microbial oil-fed fish had fewer liver vacuoles and higher mRNA levels of genes involved in β-oxidation and HDL maturation. Analyses of the intestine transcriptome revealed that microbial oil supplementation could influence the expression of genes altered by a hypercholesterolemic diet. The plasma lipidomic profiles revealed that the higher level of microbial oil tested could elevate the long-chain poly-unsaturated fatty acid content of triglyceride species and lower the concentration of several lysophosphatidylcholine and diacylglycerol molecules. Our study provides insights into the effectiveness of microbial oil against dyslipidemia in zebrafish.

Essential fatty acid requirement of juvenile meagre (Argyrosomus regius)

Meagre (Argyrosomus regius) is a fast-growing marine teleost and a promising candidate for the diversification of the Mediterranean aquaculture industry. Information on specific dietary requirements is necessary to improve the competitiveness of meagre farming. While the essential fatty acids (EFA) requirement of meagre fingerlings was previously estimated, knowledge regarding the EFA requirement of on-growing meagre juveniles is still lacking. To assess the EFA requirement of juvenile meagre, six isolipidic, isoproteic, semi-purified diets with different levels of n-3 long-chain polyunsaturated fatty acid (n-3 LC-PUFA) contents 0.0%, 0.3%, 0.6%, 0.9%, 1.2%, and 1.5% of diet dry matter (DM) were formulated and fed three times daily to triplicate groups of juvenile meagres of 35.6 ± 0.3 g for twelve weeks. Growth rates, whole body composition and fatty acid profile, liver lipid content as well as fatty acid profiles were assessed. In addition, the incidence of hepatic steatosis and granulomatosis was evaluated. Juvenile meagre fed the 0.0% n-3 LC-PUFA diet showed significantly lower growth and final body weight compared to all other treatments. There was an increase in growth of meagre with increasing dietary n-3 LC-PUFA levels and weight gain plateaued at levels above 0.9% n-3 LC-PUFA. Occurrence of granulomas examined in the liver supported the data on growth as the hepatic granulomatosis incidence in the groups fed <0.9% n-3 LC-PUFA were greater compared to fish fed diets containing higher levels of n-3 LC-PUFA. The findings of this study showed that the dietary n-3 LC-PUFA requirement of juvenile meagre for optimal growth and liver health status lays between 0.7 and 0.8% of the dietary dry matter.

Physiological Response of Grower African Catfish to Dietary Black Soldier Fly and Mealworm Meal

A six-week experiment was carried out to test the effects of total (100%) and partial (50%) replacement of fish meal in the diet of African catfish growers with black soldier fly (B) meal, yellow mealworm (M) meal, and a 1:1 combination of both (BM) on the production and health of fish. A total of 420 fish with an average initial body weight of 200 ± 0.5 g were randomly distributed in triplicate to seven diet groups (C, B50, B100, M50, M100, BM50, and BM100, respectively). The growth performance and feed utilization of fish fed with partial or total replacement levels of FM with B were not significantly affected (p > 0.05) during the 6 weeks of feeding. In contrast, significant differences were observed between the groups fed with a diet where FM was totally replaced with M meal and the control in terms of final body weight, specific growth rate, feed conversion ratio, protein efficiency ratio, and protein productive value. Among the blood plasma biochemistry parameters, total cholesterol exhibited a significant difference (p = 0.007) between the M treatments and the control diet. The fatty acid profile of the liver was changed with respect to the long-chain polyunsaturated fatty acid content in all experimental groups. Parallel with this, the upregulation of elovl5 and fas genes in liver was found in all experimental groups compared to the control. Overall, this study shows that fish meal cannot be substituted with yellow mealworm meal in the practical diet of African catfish without compromising the growth, health and feed utilization parameters.

Canola oil substitution doesn't affect growth but alters fillet quality of triploid rainbow trout

A 12-week feeding trial was conducted to evaluate the impacts of high levels of canola oil (CO) substitution for fish oil (FO) on the growth and fillet quality of triploid rainbow trout. Three isonitrogenous (46% crude protein) and isolipidic (24% crude lipids) diets were prepared. The control diet containing supplemental FO with 18.6% level was compared with the diets, in which 75% (CO75) and 100% (CO100) FO was replaced by CO, respectively. Each diet was fed to quadruplicate groups of 100 fish (initial average weight of 208 g) in freshwater cages. Results showed that CO substitution did not significantly affect survival, weight gain rate and feed conversion ratio (P > 0.05), while affected fillet organoleptic properties and nutritional value based on the multivariate statistical analysis of 124 quality indicators. Generally, high levels of CO substitution significantly increased fillet redness (a⁎, C⁎ab), relative fillet length and fillet thickness value, fillet springiness and chewiness values, fillet collagen content and crosslink level, fillet odor-active compounds concentrations, fillet inosine-5′-monophosphate (IMP), glutamic acid, histidine, sum of bitter taste compounds and sum of sour taste compounds contents, and fillet lipid and total fatty acids contents (P < 0.05). However, total substitution of FO by CO could result in high fillet fragility and low n-3 long-chain polyunsaturated fatty acids (LC-PUFA) content. In total, CO substitution did not affect growth, and could increase fillet appearance, texture, umami quality and lipid nutritional value of triploid rainbow trout, while total CO substitution was not recommended.

Recovery of Fatty Acid and Volatile Flavor Compound Composition in Farmed Tiger Puffer (Takifugu rubripes) with a Fish Oil-Finishing Strategy.

Booming fish farming results in a relative shortage of fish oil (FO) supply, meaning that alternative oils are increasingly used in fish feeds, which leads to reduction of long-chain polyunsaturated fatty acids (LC-PUFAs) and other relevant changes in fish products. This study investigated the efficacy of an FO-finishing strategy in recovering the muscle quality of farmed tiger puffer. An eight-week feeding trial (growing-out period) was conducted with five experimental diets, in which graded levels (0 (control), 25, 50, 75, and 100%) of added FO were replaced by poultry oil (PO). Following the growing-out period was a four-week FO-finishing period, during which fish in all groups were fed the control diet. Dietary PO significantly decreased the muscle LC-PUFA content, whereas in general, the FO-finishing strategy recovered it to a level comparable with that of the group fed FO continuously. The recovery efficiency of EPA was higher than that of DHA. Dietary PO also led to changes of volatile flavor compounds in the muscle, such as butanol, pentenal, and hexenal, whereas the FO-finishing strategy mitigated the changes. In conclusion, the FO-finishing strategy is promising in recovering the LC-PUFA and volatile-flavor-compound composition in farmed tiger puffer after the feeding of PO-based diets.

Function of the Polyketide Synthase Domains of Schizochytrium sp. on Fatty Acid Synthesis in Yarrowia lipolytica.

It is well known that polyunsaturated fatty acids (PUFAs) in Schizochytrium sp. are mainly synthesized via the polyketide synthase (PKS) pathway. However, the specific mechanism of PKS in fatty acid synthesis is still unclear. In this work, the functions of ORFA, ORFB, ORFC, and their individual functional domain genes on fatty acid synthesis were investigated through heterologous expression in Yarrowia lipolytica. The results showed that the expression of ORFA, ORFB, ORFC, and their individual functional domains all led to the increase of the very long-chain PUFA content (mainly eicosapentaenoic acid). Furthermore, the transcriptomic analysis showed that except for the 3-ketoacyl-ACP synthase (KS) domain of ORFB, the expression of an individual functional domain, including malonyl-CoA: ACP acyltransferase, 3-hydroxyacyl-ACP dehydratase (DH), 3-ketoacyl-ACP reductase, and KS domains of ORFA, acyltransferase domains of ORFB, and two DH domains of ORFC resulted in upregulation of the tricarboxylic acid cycle and pentose phosphate pathway, downregulation of the triacylglycerol biosynthesis, fatty acid synthesis pathway, and β-oxidation in Yarrowia lipolytica. These results provide a theoretical basis for revealing the function of PKS in fatty acid synthesis in Y. lipolytica and elucidate the possible mechanism for PUFA biosynthesis.

Effects of Pork Backfat Replacement with Emulsion Gels Formulated with a Mixture of Olive, Chia and Algae Oils on the Quality Attributes of Pork Patties.

This paper reports on the development of new emulsion gels containing a mixture of olive, chia and algae oil emulsified with soy protein isolate and stabilized by two different cold gelling agents, gelatin (EGEL) and chitosan (ECHIT), and to evaluate their potential use as pork backfat replacers in cooked pork patties. Reformulated patties were produced by half and full pork backfat replacement and compared to normal fat patties and reduced fat content patties made by replacing half of the added fat with water. Color parameters, pH and thermal stability of the emulsion gels were determined at processing and after 10 days of refrigerated storage. Proximate composition, fatty acid profile, technological properties and sensory attributes were evaluated after patty processing, while color parameters, pH and lipid oxidation were monitored in patties during 15 days of refrigerated storage (4 °C). Reformulated patties showed significant improvements of the lipid profile (lower saturated fatty acid content and n-6/n-3 ratio and higher long-chain polyunsaturated fatty acid content) as compared to the controls. In terms of technological properties, chitosan was more effective than gelatin as a stabilizer of the emulsion gel. All reformulated patties showed a good evolution of lipid oxidation during storage and acceptable sensory attributes.

Placental Fatty Acid Metabolism and Transport in a Rat Model of Gestational Diabetes Mellitus.

Gestational diabetes mellitus (GDM) is a form of heightened insulin resistance triggered during gestation. This study examines how insulin resistance alters placental long-chain polyunsaturated fatty acid (LCPUFA) transport and metabolism in a rat model of lean GDM. Pregnant Sprague Dawley rats were administered with S961, an insulin receptor antagonist (30 nmol/kg s.c. daily), or vehicle from gestational day (GD) 7 to 20. Daily maternal body weight, food, and water intake were measured. Blood pressure assessment and glucose tolerance test were done on GD20. Fetal plasma and placenta were collected on GD20 and processed for fatty acid measurement using LC-mass spectrometry. The expression of fatty acid metabolism-related genes in the placenta was assessed using RT2 Profiler PCR arrays. The results were validated by qRT-PCR. Blockade of insulin receptors with S961 in pregnant rats resulted in glucose intolerance with increased fasting glucose and insulin levels. Maternal body weight gain and food and water intake were not affected; however, S961 significantly increased maternal blood pressure and heart rate. The placenta n3 and n6 LCPUFA concentrations were significantly decreased by 8% and 11%, respectively, but their levels in the fetal plasma were increased by 15% and 4%. RT2 profiler arrays revealed that placental expressions of 10 genes related to fatty acid β-oxidation (Acaa1a, Acadm, Acot2, Acox2, Acsbg1, Acsl4, Acsm5, Cpt1b, Eci2, Ehhadh) and 3 genes related to fatty acid transport pathway (Fabp2, Fabp3, Slc27a3) were significantly upregulated. In summary, lack of insulin action increased the expression of genes related to placental fatty acid β-oxidation and transport with an increased transfer of LCPUFA to the fetus. The increased lipid levels routed toward the fetus may lead to fat adiposity and later-life metabolic dysfunction.

HIGH OLEIC SUNFLOWER OIL DECREASES ENDOGENOUS BIOSYNTHESIS OF ENERGY FATTY ACIDS AND INCREASES ENDOGENOUS BIOSYNTHESIS OF ω-3 LONG-CHAIN PUFA

The work shows that Fatty acids of dietary fats provide two main functions in the human and animal body: energy and structural-regulatory, Polyunsaturated fatty acids (PUFA) are the basis of membrane lipids of all cells of the body The structure and functional activity of cells, their resistance to pathogenic factors depends on the ratio of ω-6 / ω-3 PUFA. Аdherence to recommended metabolic energy reserves in poultry feed is essential to optimize feed costs. The use of oils or fats is a common economic practice in modern poultry production. Energy functions are carried out due to the oxidation of energy fatty acids in mitochondria, which include, first of all, palmitic (С16:0), palmitooleic (С16:0), stearic (С18:1) and oleic (С18:1). In addition to providing energy, edible oil can also enhance dietary palatability, reduce dustiness, and increase lipoprotein hydrolysis to promote the production of essential fatty acids. Adipose tissue should be considered not only as a source of various fatty acids, but also as an important endocrine organ that takes an active part in the activity of the immune system. To determine the effect of a diet with high oleic sunflower oil on the content of energy fatty acids (EFA) and long-chain PUFA (LCPUFA) in rat liver lipids. We used high oleic sunflower oil (HOSO) containing 85.5% oleic acid. The rats were fed a fat-free diet (FFD) and diets with 5 or 15% HOSO for 35 days. Lipids were extracted from the liver and separated into three fractions: neutral lipids (NL), phospholipids (PL) and free fatty acids (FFA). The fatty acid composition of lipid fractions was determined by gas chromatography. FFA are the sum of the following acids:С16:0, С16:1, С18:0, С18:1andС18:2. LCPUFA are presented С20:4 ω-6, С20:5 ω-3, С22:5 ω-3and С22:6 ω-3. Most of all, EFA is contained in the NL fraction (89%), then in the PL fraction (79%), and least of all in the FFA fraction (68%). LCPUFA is found most of all in the FFA fraction (20%), then in the PL fraction (13%), and least of all in the NL fraction (2%). In rats that received fat diets, the content of EFA increased in the NL fraction by 2-3%, in the FFA fraction by 5-8%, and did not change in the PL fraction. The content of LCPUFA ω-6 (arachidonic acid) with fat nutrition dose-dependently decreases in the fraction of NL and FFA and does not change in the fraction of PL. On the contrary, the content of ω-3 LCPUFA increases in rats treated with HOSO in all lipid fractions. Also, the ω-6/ω-3 LCPUFA ratio is significantly reduced in rats treated with HOSO. Consumption of HOSO stimulates endogenous biosynthesis of ω-3 LCPUFA.

A multi-species direct-fed microbial supplement alters the milk lipidome of dairy cows

The study evaluated the effects of supplementing a multi-species direct-fed microbial (DFM) on the milk lipidome of lactating dairy cows. Twenty-four multiparous Holstein cows (41 ± 7 d in milk) were used in a randomized complete block design with experimental duration of 91 d. Cows were blocked based on energy-corrected milk yield from a 14-d pretreatment period, and were assigned randomly within each block to the following treatments: (1) control (CON): corn silage-based total mixed ration without DFM; or (2) BOV+: basal diet top-dressed with a DFM containing a mixture of Lactobacillus animalis (LA-51), Propionibacterium freudenreichii (PF-24), Bacillus subtilis (CH201), and Bacillus licheniformis (CH200) at 11.8 × 109 cfu/d. Milk samples were taken from morning and evening milkings on 2 consecutive days of each week of the pretreatment and treatment periods. Separate composites of pretreatment period and treatment period samples were prepared for individual cows and used for lipidome analysis. Lipidome analysis of the milk samples was performed using an ultra-high-performance liquid chromatograph linked to a quadrupole time-of-flight mass spectrometer in both positive and negative ionizations. The relative concentrations of 14 lipid species, including long-chain polyunsaturated fatty acids (LC-PUFA) such as FA 20:8 and FA 28:7 and triacylglycerides (TG) such as TG 40:3 and TG 54:2, were increased [false discovery rate (FDR) ≤0.05], whereas 13 lipid species, including saturated FA 24:0 and TG 40:0 were decreased (FDR ≤0.05) by supplemental BOV+. The relative concentration of de novo FA in milk was greater, whereas that of preformed FA was lower in dairy cows supplemented with BOV+. Results from this study demonstrate the potential of a DFM containing L. animalis, P. freudenreichii, Bacillus subtilis, and B. licheniformis to alter the milk lipidome in lactating dairy cows toward increased relative concentration of LC-PUFA, which might offer a healthier profile of FA to consumers with its associated health benefits.

Fish oil replacement by beef tallow in juvenile turbot diets: Effects on growth performance, body composition and volatile flavor compounds in the muscle

A 12-week feeding trial was conducted to evaluate the effects of dietary fish oil (FO) replacement by beef tallow (BT) on the growth performance and body composition of juvenile turbot (average initial weight, 19.6 g). The control diet contained 6% added FO (of dry matter, Diet FO-C). Beef tallow was supplemented into Diet FO-C, replacing added FO at different levels, i.e., 25%, 50%, 75%, and 100%, formulating the other 4 experimental diets, designated as 25BT, 50BT, 75BT, and 100BT, respectively. The feeding trial was conducted in a flow-through seawater system. Each diet was randomly fed to triplicate tanks (30 fish in each tank). The results showed that a cubic regression relationship was observed between weight gain and dietary FO replacement level. Although total FO replacement by BT significantly reduced the growth of juvenile turbot, no significant difference was observed between FO-C and 75BT. Diet BT decreased the whole-body crude lipid content but increased the whole-body moisture and ash contents. Dietary BT regulated the proximate composition of fish tissues in a dose dependent manner. High dietary BT levels did not reduce the n-3 long-chain polyunsaturated fatty acid content (% total fatty acid) in the muscle. Partial FO replacement (25 and 50%) by BT even significantly increased the muscle DHA content. The fatty acid composition of the liver, subcutaneous adipose tissue around the fin, and intestine generally reflected those of the diets. No significant difference was observed in muscle and liver mitochondrial DNA copy number among groups, indicating the similar general energy supply status. Dietary BT significantly reduced the concentration of triacylglycerol, cholesterol and malondialdehyde in the serum. The volatile flavor compound in muscle was analyzed with gas chromatography-ion migration spectrometry (GC-IMS). Dietary BT resulted in lower number and abundance of flavor aldehydes and alcohols in the muscle. In conclusion, beef tallow can replace 75% added fish oil (appr. 45% of total fish oil including the residual fish oil in fishmeal) in the diets of turbot, without reducing fish growth. Dietary beef tallow significantly affected the body composition and volatile flavor compound composition in the muscle.

Export of dietary lipids via emergent insects from eutrophic fishponds

Fishponds, despite being globally abundant, have mainly been considered as food production sites and have received little scientific attention in terms of their ecological contributions to the surrounding terrestrial environment. Emergent insects from fishponds may be important contributors of lipids and essential fatty acids to terrestrial ecosystems. In this field study, we investigated nine eutrophic fishponds in Austria from June to September 2020 to examine how Chlorophyll-a concentrations affect the biomass of emergent insect taxa (i.e., quantity of dietary subsidies; n = 108) and their total lipid and long-chain polyunsaturated fatty acid content (LC-PUFA, i.e., quality of dietary subsidies; n = 94). Chironomidae and Chaoboridae were the most abundant emergent insect taxa, followed by Trichoptera, Ephemeroptera, and Odonata. A total of 1068 kg of emergent insect dry mass were exported from these ponds (65.3 hectares). Chironomidae alone exported 103 kg of total lipids and 9.4 kg of omega-3 PUFA. Increasing Chl-a concentrations were associated with decreasing biomass export and a decrease in total lipid and LC-PUFA export via emergent Chironomidae. The PUFA composition of emergent insect taxa differed significantly from dietary algae, suggesting selective PUFA retention by insects. The export of insect biomass from these eutrophic carp ponds was higher than that previously reported from oligotrophic lakes. However, lower biomass and diversity are exported from the fishponds compared to managed ponds. Nonetheless, our data suggest that fishponds provide crucial ecosystem services to terrestrial consumers by contributing essential dietary nutrients to consumer diets via emergent insects.

Effects of ginger (Zingiber officinale) supplementation on testicular histology, semen characteristic, blood plasma parametersand reproductive performance in aged broiler breeder roosters.

Higher long-chain polyunsaturated fatty acids contents in roosters' sperm plasma membrane along with age-related decrease in antioxidant defense make the spermatozoa very susceptible to lipid peroxidation. Ginger root contains abundant amounts of gingerol, shogaols, gingerdiol and other active compounds, which known as antioxidant compounds to enhance semen quality. The goal of the study was to evaluate the effect of dietary supplementation of ginger root on semen quality, blood chemistry, immune response, testicular histology and reproductive performance of Ross-308 breeder roosters from 47 to 60 weeks of age. The feeding of ginger root resulted in an increase in parameters related to sperm forward motility and seminal total antioxidant capacity (TAC), and following there was a tendency to increase and decrease in seminal superoxide dismutase activity and malondialdehydeconcentration, respectively; however, sperm concentration was not affected. There was an increase and tendency to increase in blood total protein and TAC in the supplemented grouprespectively. The roosters fed ginger supplemented diet had a higher spermiation index; and following there was tendency to increase seminal tubes spermatozoids number (p = 0.056) and repopulation index (p = 0.058). Despite the improved seminal antioxidant status and a tendency to lower embryonic mortality in the ginger-received group, the fertility and hatchability rate of roosters were statistically insignificant. Supplementations of ginger root in ageing rooster's diet had a beneficial effect on sperm motility, seminal antioxidant statusand testicular spermiation index.

Randomized controlled trial of early arachidonic acid and docosahexaenoic acid enteral supplementation in very preterm infants.

ObjectiveTo evaluate changes in blood long-chain polyunsaturated fatty acid (LCPUFA) and oxylipin concentrations in very preterm infants from birth to 36 weeks’ postmenstrual age (WPA) after providing an emulsified arachidonic acid (ARA):docosahexaenoic acid (DHA) supplement at two different concentrations.Study designThis prospective, randomized trial assigned infants to receive a supplement (1) 80:40 group (80 mg/kg/day ARA and 40 mg/kg/day DHA, n = 9) or (2) 120:60 group (120 mg/kg/day ARA and 60 mg/kg/day DHA, n = 9). Infants received supplement daily from birth until 36 WPA. At baseline, 21 days of life and 36 WPA, the LCPUFAs were measured in plasma by gas chromatography/mass spectrophotometry. Additionally, LCPUFAs and oxylipins were analyzed in whole blood by ultra-high-performance liquid chromatography-tandem mass spectrometry. Furthermore, a sample of oral mucosa was obtained to analyze single-nucleotide polymorphism located in the FADS1 gene by PCR.ResultsGestational age was similar between groups (80:40 = 28+6 [27+3; 30+3] completed weeks+days; 120:60 = 29+6 [27+3; 30+5] completed weeks+days, p = 0.83). At 36 WPA, the change in plasma ARA was significantly different between groups (80:40 group = 0.15 [−0.67; 0.69] %nmol, 120:60 = 1.68 [1.38; 3.16] %nmol, p = 0.031). In whole blood, the levels of ARA-derived oxylipins (5-, 8-, 9-, 11-, 15-HETE and 8,9-EET) and EPA-derived oxylipins (18-HEPE) significantly increase from baseline to 36 WPA in the 120:60 group than the 80:40 group.ConclusionSupplementation at high doses (120:60 mg/kg/day) increased levels of ARA, and EPA- and ARA-derived oxylipins compared to low doses (80:40 mg/kg/day). Differences were detected in EPA metabolites without a significant increase in plasma DHA.

Oils Combination with Microalgal Products as a Strategy for Increasing the N-3 Long-Chain Polyunsaturated Fatty Acid Content in Fish Oil-Free Diets for Meagre (Argyrosomus regius)

Diversification of species and ingredients is essential for further developing aquaculture production. The present study aimed to evaluate the potential of a blend of microalgae oils and poultry oil as total replacers of fish oil in aquafeeds, a fast-growing species for aquaculture diversification, that was shown to require high dietary n-3 LC-PUFA levels. For that purpose, meagre juveniles ( 2.74 ± 0.01 g initial body weight) were fed one of the four experimental diets for 30 days. A control diet (FO diet) was based on 5% fish oil and 7% of rapeseed oil, whereas in the other three diets, fish oil was totally replaced by either poultry oil only (PO diet), or blending poultry oil and one of two commercial algal oils (ED and DD diets). Growth performance, tissue composition, and the expression of genes related to fatty acid biosynthesis, antioxidant defense system, and heat shock proteins were determined. Diets with blends of poultry and microalgae oils supported good growth and feed utilization of meagre. Besides, these diets maintained high DHA tissue contents and good fillet lipid quality indices, like in those fish fed the control diet containing fish oil. Furthermore, the meagre fed ED diet showed the highest expression of gpx, in agreement with the highest dietary polyunsaturated fatty acid content. These results demonstrated the good potential of blending these two commercial microalgae oils with poultry oil to completely replace fish oil cost-effectevily in diets for meagre. In contrast, PO as the sole replacer of fish oil was not able to support fish growth performance and tissue contents of n-3 LC-PUFA, leading to an increased thrombogenic index in fish fillets. Additionally, the low dietay n-3 LC-PUFA content of PO diet upregulated the relative expression offads2 while downregulating gpx compared to microalgal diets.

In vitro Digestion Characteristics of Hydrolyzed Infant Formula and Its Effects on the Growth and Development in Mice.

Infant formula, an important food for babies, is convenient and nutritious, and hydrolyzed formulas have attracted much attention due to their non-allergicity. However, it is uncertain whether hydrolyzed formulars cause obesity and other side effects in infants. Herein, three infant formulas, standard (sIF), partially hydrolyzed (pHIF), and extensively hydrolyzed (eHIF), were analyzed in an in vitro gastrointestinal digestion model. With increasing degree of hydrolysis, the protein moleculars, and allergenicity of the proteins decreased and the long-chain polyunsaturated fatty acid content increased. Moreover, the digestion model solutions quickly digested the small fat globules and proteins in the hydrolyzed formula, allowing it to become electrostatically stable sooner. The eHIF-fed mice presented larger body sizes, and exhibited excellent exploratory and spatial memory abilities in the maze test. Based on villus height and crypt depth histological characterizations and amplicon sequencing, eHIF promoted mouse small intestine development and changed the gut microbiota composition, eventually favoring weight gain. The mouse spleen index showed that long-term infant formula consumption might be detrimental to immune system development, and the weight-bearing swimming test showed that eHIF could cause severe physical strength decline. Therefore, long-term consumption of infant formula, especially eHIF, may have both positive and negative effects on mouse growth and development, and our results might shed light on feeding formula to infants.