Tissue Fatty Acid Composition Research Articles

Substituting ground woody plants for cottonseed hulls in lamb feedlot diets: carcass characteristics, adipose tissue fatty acid composition, and sensory panel traits

Effects of using ground woody plants in Rambouillet wether lamb (n = 48) feedlot diets on carcass characteristics, adipose tissue fatty acid composition, and sensory panel traits were evaluated. In a randomized design study with two feeding periods (period 1 = fed a 70% concentrate diet from days 0 to 27; period 2 = fed an 86% concentrate diet from days 28 to 57), lambs were individually fed six diets that differed only by roughage source (n = 8 animals/treatment; initial BW = 32.9 ± 3.2 kg): cottonseed hulls (CSH; control) or ground wood consisting of either redberry (RED), blueberry (BLUE), one-seed (ONE), or eastern red cedar (ERC) Juniperus spp., or Prosopis glandulosa (MESQ). After 57 d, the lambs were humanely harvested and after chilling (2 ± 1 oC) 24 h, carcasses were evaluated for carcass traits. At 48 h postmortem, the longissimus thoracis (LT) was removed from the left side of the carcass, and after freezing for no more than 3 mo, were thawed for 24 h, cooked, and evaluated by a trained sensory panel. Additionally, volatile aroma chemicals on the LT were determined by gas chromatograph/mass spectrometer/olfactory (GC/MS/OF, respectively) analyses. Lamb HCW was greater (P = 0.01) for lambs fed CSH compared with all other diets, but lambs had similar (P > 0.08) LM area, back fat thickness, leg circumference, and body wall. Neither adipose tissue fatty acid composition (P > 0.08) nor trained sensory panel evaluation (P > 0.18) was affected by finishing diet roughage source. Of the 81 volatile aroma compounds found in the grilled lamb chops, only seven were affected (P < 0.05) by dietary roughage source and included 1-pentanol (a sweet, pleasant aroma), heptenal (a fishy aroma), pentanal (fermented, bready aroma description), 1-(1H-pyrol-2yl)-ethanone (caramel-like), 2-heptanone (cheesy, banana, fruity aromatic), 6,7-dodecanedione (unknown aroma), and butanoic acid (a sweaty, rancid aroma). The addition of any of four species of juniper or mesquite may be substituted for CSH without negatively affecting carcass fat and muscling, fatty acid, or sensory traits.

Effect of selected plant species within biodiverse pasture on in vitro fatty acid biohydrogenation and tissue fatty acid composition of lamb

The effect of botanical diversity on supply of polyunsaturated fatty acids (PUFA) to ruminants in vitro, and the fatty acid (FA) composition of muscle in lambs was investigated. Six plant species, commonly grown as part of UK herbal ley mixtures (Trifolium pratense, Lotus corniculatus, Achillea millefolium, Centaurea nigra, Plantago lanceolata and Prunella vulgaris), were assessed for FA profile, and in vitro biohydrogenation of constituent PUFA, to estimate intestinal supply of PUFA available for absorption by ruminants. Modelling the in vitro data suggested that L. corniculatus and P. vulgaris had the greatest potential to increase 18:3n-3 supply to ruminants, having the highest amounts escaping in vitro biohydrogenation. Biodiverse pastures were established using the six selected species, under-sown in a perennial ryegrass-based sward. Lambs were grazed (~50 days) on biodiverse or control pastures and the effects on the FA composition of musculus longissimus thoracis (lean and subcutaneous fat) and musculus semimembranosus (lean) were determined. Biodiverse pasture increased 18:2n-6 and 18:3n-3 contents of m. semimembranosus (+14.8 and +7.2 mg/100 g tissue, respectively) and the subcutaneous fat of m. longissimus thoracis (+158 and +166 mg/100 g tissue, respectively) relative to feeding a perennial ryegrass pasture. However, there was no effect on total concentrations of saturated FA in the tissues studied. It was concluded that enhancing biodiversity had a positive impact on muscle FA profile reflected by increased levels of total PUFA.

Addition of Emulsifiers to Hydrogenated Soybean Oil‐Based Feeds for Yellowtail

AbstractHydrogenated soybean oil can be used to spare fish oil in aquafeeds, but lipid digestibility may be a limiting factor. We evaluated the performance and tissue fatty acid composition of juvenile Yellowtail Seriola dorsalis that were fed diets containing menhaden fish oil (positive control), hydrogenated soybean oil (negative control), or hydrogenated soybean oil amended with 1% mixed bile acids, casein, whey protein, or monoglycerides as emulsifying agents. Juvenile fish (~10 g) were stocked in a semi‐closed recirculation aquaculture system (15 fish/tank), diets were randomly assigned to tanks in triplicate (N = 3), and fish were fed in slight excess of estimated apparent satiation amounts for 6 h/d with belt feeders. After 8 weeks, production performance was equivalent for fish fed the positive control and negative control feeds; amending the hydrogenated soybean oil‐based feeds with casein, whey protein, or monoglycerides did not affect performance, whereas adding mixed bile acids significantly impaired performance (weight gain = 655–681% versus 459%; survival = 98–100% versus 49%; feed conversion ratio = 1.19–1.22 versus 1.56). Whole‐body fatty acid composition tended to mirror dietary composition except that fish receiving the hydrogenated soybean oil‐based feeds exhibited disproportionately lower levels of saturated fatty acids and higher levels of monounsaturated fatty acids, long‐chain polyunsaturated fatty acids, and n‐3 and n‐6 fatty acids compared to dietary levels. Results suggest that casein, whey protein, and monoglycerides could be added to saturated fatty acid‐rich hydrogenated soybean oil‐based diets to reduce tissue fatty acid profile distortion, but production performance might not be enhanced. Of all the hydrogenated soybean oil‐based feeds in this study, the one supplemented with casein resulted in a whole‐body fatty acid profile closest to that of fish fed the fish oil‐based feed. Mixed bile acids should not be added due to the resulting negative impacts on survival and growth.

Fatty acids and beyond: Fillet nutritional characterisation of rainbow trout (Oncorhynchus mykiss) fed different dietary oil sources

A considerable body of literature exists concerning the use of marine-derived raw materials in aquaculture feed formulations and the resulting modifications of the health promoting qualities of farmed fish. However, these investigations and reports are fundamentally limited to fatty acids and little is known regarding the other nutritional characteristics of cultured fish and seafood products. This knowledge gap, often coupled with inaccurate or incomplete media reports, generates consumer confusion and mistrust in relation to farmed fish quality. The aim of the present study was therefore to characterise not only the fatty acid composition, but also the resulting protein, amino acid and micronutrient composition of rainbow trout fed diets containing fish oil or vegetable oils. To achieve this, triplicate groups of rainbow trout (Oncorhynchus mykiss) were subjected to two distinct vegetable oil- based diets (one rich in alpha-linolenic acid, 18:3n-3, ALA and the other rich in linoleic acid, 18:2n-6, LNA) and a traditional n-3 long chain polyunsaturated fatty acid (LC-PUFA) rich, fish oil-based diet over a 126 day period. Growth performance and feed utilisation parameters as well as tissue fatty acid composition, amino acid composition, vitamin, mineral and trace element concentration in fish fillets were subsequently assessed. Expectedly, major differences were evident between treatments in relation to fatty acid composition, where for the most part fillet composition reflected that of the diet. Notably, no differences were observed regarding fillet amino acid composition, as was also the case for the vast majority of vitamins, minerals and trace elements. Therefore, with the exception of the fatty acid profile and vitamin A concentration, other beneficial nutritional qualities of fish are fundamentally maintained and unaffected when alternative oil sources are implemented in aquaculture feed formulations, maintaining cultured rainbow trout a nutritious and nourishing product for human consumption.

Comparative analysis of effects of dietary arachidonic acid and EPA on growth, tissue fatty acid composition, antioxidant response and lipid metabolism in juvenile grass carp,Ctenopharyngodon idellus

Four isonitrogenous and isoenergetic purified diets containing free arachidonic acid (ARA) or EPA (control group), 0·30 % ARA, 0·30 % EPA and 0·30 % ARA+EPA (equivalent) were designed to feed juvenile grass carp (10·21 (sd 0·10) g) for 10 weeks. Only the EPA group presented better growth performance compared with the control group (P<0·05). Dietary ARA and EPA were incorporated into polar lipids more than non-polar lipids in hepatopancreas but not intraperitoneal fat (IPF) tissue. Fish fed ARA and EPA showed an increase of serum superoxide dismutase and catalase activities, and decrease of glutathione peroxidase activity and malondialdehyde contents (P<0·05). The hepatopancreatic TAG levels decreased both in ARA and EPA groups (P<0·05), accompanied by the decrease of lipoprotein lipase (LPL) activity in the ARA group (P<0·05). Fatty acid synthase (FAS), diacylglycerol O-acyltransferase and apoE gene expression in the hepatopancreas decreased in fish fed ARA and EPA, but only the ARA group exhibited increased mRNA level of adipose TAG lipase (ATGL) (P<0·05). Decreased IPF index and adipocyte sizes were found in the ARA group (P<0·05). Meanwhile, the ARA group showed decreased expression levels of adipogenic genes CCAAT enhancer-binding protein α, LPL and FAS, and increased levels of the lipid catabolic genes PPAR α, ATGL, hormone-sensitive lipase and carnitine palmitoyltransferase 1 (CPT-1) in IPF, whereas the EPA group only increased PPAR α and CPT-1 mRNA expression and showed less levels than the ARA group. Overall, dietary EPA is beneficial to the growth performance, whereas ARA is more potent in inducing lipolysis and inhibiting adipogenesis, especially in IPF. Meanwhile, dietary ARA and EPA showed the similar preference in esterification and the improvement in antioxidant response.

Alterations in fatty acid metabolism in response to obesity surgery combined with dietary counseling

Background:The effects of obesity surgery on serum and adipose tissue fatty acid (FA) profile and FA metabolism may modify the risk of obesity-related diseases.Methods:We measured serum (n=122) and adipose tissue (n=24) FA composition and adipose tissue mRNA expression of genes regulating FA metabolism (n=100) in participants of the Kuopio Obesity Surgery Study (KOBS, age 47.2±8.7 years, BMI 44.6±6.0, 40 men, 82 women) before and one year after obesity surgery. As part of the surgery protocol, all the subjects were instructed to add sources of unsaturated fatty acids, such as rapeseed oil and fatty fish, into their diet. The results were compared with changes in serum FA composition in 122 subjects from the Finnish Diabetes Prevention study (DPS) (age 54.3±7.1 years, BMI 32.2±4.6, 28 men, 94 women).Results:The proportion of saturated FAs decreased and the proportion of n-3 and n-6 FAs increased in serum triglycerides after obesity surgery (all P<0.002). Weight loss predicted changes in quantitative amounts of saturated FAs, monounsaturated FAs, n-3 and n-6 FAs in triglycerides (P<0.002 for all). Moreover, the changes in adipose tissue FAs reflected the changes in serum FAs, and some of the changes were associated with mRNA expression of elongases and desaturases in adipose tissue (all P<0.05). In line with this the estimated activity of elongase (18:1 n-7/16:1 n-7) increased significantly after obesity surgery in all lipid fractions (all P<4 × 10−7) and the increase in the estimated activity of D5D in triglycerides was associated with higher weight loss (r=0.415, P<2 × 10−6). Changes in serum FA profile were similar after obesity surgery and lifestyle intervention, except for the change in the absolute amounts of n-3 FAs between the two studies (P=0.044).Conclusions:Beneficial changes in serum and adipose tissue FAs after obesity surgery could be associated with changes in endogenous metabolism and diet.

Replacement of fish oil with vegetable oil blends in feeds for greater amberjack (Seriola dumerili) juveniles: Effect on growth performance, feed efficiency, tissue fatty acid composition and flesh nutritional value

Replacement of fish oil with vegetable oil blends in feeds for greater amberjack (<i>Seriola dumerili</i>) juveniles: Effect on growth performance, feed efficiency, tissue fatty acid composition and flesh nutritional value

Changes of Leaf Membrane Fatty Acid Composition and Saturation Level of Warm‐Season Turfgrass during Drought Stress

Although it is known that drought tolerance can be associated with membrane fatty acid (FA) unsaturation, a relevant study is lacking in zoysiagrass (Zoysia spp.) and St. Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze.]. Our objectives were (i) to substantiate that variation exists among species and genotypes for leaf tissue FA composition under well‐watered conditions; (ii) to evaluate the relationship between well‐watered leaf FA composition and turf performance under drought stress; and (iii) to determine if modifications in FA content occur during drought stress and if the changes associate with improved drought tolerance. Nine genotypes of three species were subjected to both controlled dry down and well‐watered conditions for 12 d in a greenhouse. Plants were evaluated for cumulative water use, transpiration response, turfgrass quality, and leaf FA composition (palmitic acid, stearic acid, palmitoleic acid, hexadecadienoic acid, oleic acid, linoleic acid, and linolenic acid). St. Augustinegrass had a constitutively higher unsaturation FA fraction than two zoysiagrass species, owing to its higher linolenic acid and low palmitic acid fractions. During dry down, relative FA contents remained stable and no early unsaturation alteration was found. Two genotypes, ‘UF182’ Japanese lawngrass (Z. japonica Steud.) and ‘Zeon’ manilagrass [Z. matrella (L.) Merr.], displayed an increase in unsaturated FAs when severe drought stress occurred (rapid decline in turfgrass quality), which was associated with good turfgrass quality and apparent drought tolerance. The result in zoysiagrass supports previous reports suggesting increased levels of linolenic acid under drought stress to be a defensive mechanism.

349 Duration of high-concentrate diet prior to forage finishing I: Effects on animal performance, glucose/insulin levels, carcass traits, and tissue fatty acid composition of beef steers

349 Duration of high-concentrate diet prior to forage finishing I: Effects on animal performance, glucose/insulin levels, carcass traits, and tissue fatty acid composition of beef steers

Adipose tissue fatty acids composition in patients with nephrolithiasis

Adipose tissue fatty acids composition in patients with nephrolithiasis

Increasing dietary EPA and DHA influence estimated fatty acid desaturase activity in systemic organs which is reflected in the red blood cell in mice

Delta-5 (D5D) and delta-6 (D6D) desaturase are key enzymes in fatty acid (FA) metabolism. Dietary eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) may alter tissue FA composition via D5D and D6D. The purpose was to determine the relationship between dietary EPA + DHA, estimated desaturase activities of various tissues and the reflection of desaturase activity in the red blood cell (RBC). Mice were fed diets with increasing percent of energy from EPA + DHA. Phospholipid FA composition of heart, muscle, spleen, lung, adipose tissues and RBC were analysed. D5D and D6D enzyme activity estimates (EAE) were calculated as the ratio of 20:4/20:3 and 20:3/18:2, respectively. D5D EAE decreased in all tissues, except muscle, with increasing dietary EPA + DHA. RBC D5D EAE positively correlated with D5D EAE in all tissues. RBC D6D EAE positively correlated with muscle and inversely correlated with adipose D6D EAE. Our findings suggest differential influence of dietary EPA + DHA upon tissue desaturase activities.

Regulation of growth, tissue fatty acid composition, biochemical parameters and lipid related genes expression by different dietary lipid sources in juvenile black seabream, Acanthopagrus schlegelii

The effects of different dietary lipid sources on physiological characteristics and lipid metabolism relevant genes expression were assessed in juvenile black seabream Acanthopagrus schlegelii. 720 black seabream juveniles (initial weight was 5.4±0.0g) were randomly allocated in 18 floating net cages corresponding to triplicate cages of the six dietary treatments, and the 8-week feeding trail was conducted. Five isonitrogenus and isolipidic diets were formulated to contain lipid sources: coconut oil (CO), perilla oil (PO), sunflower oil (SO), arachidonic acid (ARA) and eicosapentaenoic acid combined with docosahexaenoic acid (EPA+DHA), and fish oil (FO) was set as a control group. The results showed that weight gain (WG), specific growth rate (SGR) and feed efficiency (FE) in fish fed diets containing FO and EPA+DHA were significantly higher than CO. In serum, the highest activity of glutathione peroxidase (GSH-PX) and glutathione (GSH) content were recorded in fish fed EPA+DHA. The significantly highest content of malondialdehyde (MDA) was observed in fish fed the EPA+DHA and FO diets. The maximum hepatic content of MDA and the minimum activity of superoxide dismutase (SOD) were all found in fish fed the diet containing EPA+DHA. High contents of cholesterol (CHOL) and triacylglycerol (TAG) were found in fish fed SO, whereas glucose (GLU) content in fish fed EPA+DHA was significantly higher than in the other treatments. Fish fed FO had the highest hemoglobin (HGB) among treatments. The anabolic pathway relevant genes: accα, fas and srebp-1 were up-regulated by dietary SO and PO. Whereas, the catabolic pathway relevant genes: lpl, cpt1a, atgl, hsl and pparα were down-regulated by dietary CO. Furthermore, the long chain polyunsaturated fatty acid (LC-PUFA) biosynthesis relevant genes elovl5 and fads2 were significantly up-regulated by dietary SO and PO. The present study focused on comparing the effects of different dietary lipid sources on biochemical characteristics and lipid metabolism relevant genes expression in black seabream. Overall, it demonstrated that physiological-biochemical characteristics as well as lipid metabolism relevant genes expression were significantly regulated by different dietary lipid sources. Moreover, dietary PO and SO regulated some physiological and biochemical indicators. These findings could contribute to optimize aquatic feeds when considering selection of optimal lipid sources or their optimal proportion in the future.

Methionine supplementation augments tissue n-3 fatty acid and tocopherol content in broiler birds fed flaxseed

Methionine (Met) is the first limiting amino acid in meat-type broiler chicken diets and serves as a lipotropic agent with antioxidant properties. The objectives of the current study is based on the hypothesis that Met supplementation will enhance n-3 fatty acid (FA) status, antioxidant content, lipid stability, and production indices in broilers fed flax. The effect of Met supplementation (50 and 100% above Cobb 500 requirement level) on tissue FA composition, tocopherol (Toc) content, lipid oxidation products, and growth performance of broilers fed flax is investigated. One hundred and twenty (n=120) day-old Cobb chicks were fed corn-soybean meal-based diet containing 0% flax, (Control), 15% flax (Diet 1), Diet 1+50% more Met (Diet 2), and Diet 1+100% more Met (Diet 3) for 42 days. Total lipids in liver and adipose tissue was lowest in Diet 3 (P<0.05). Feeding flax led to a reduction total lipids in breast muscle (P<0.05) and was not affected by Met level (P>0.05). α-Linolenic acid (18:3n-3) was highest in thigh muscle and liver of Diet 3 and adipose tissue of chickens fed Diet 2 and Diet 3 (P<0.05). Total long chain (>20C) n-3 FA was highest in the breast muscle of chickens fed Diet 2 and Diet 3 (P<0.05). Total saturated FA were lowest in the breast and thigh muscle of Diet 3 fed birds (P<0.05). Addition of Met led to an increase in α-Toc in breast muscle in birds fed Diet 2 and Diet 3 (P<0.05). Lipid oxidation products were lower in the thigh muscle and adipose tissue of birds fed Diet 2 and Diet 3 than Diet 1 and Control (P<0.05). Body weight gain was lowest in birds fed flax (P<0.05). Met supplementation had no effect on weight gain or feed conversion in birds fed flax (P>0.05). No effect of diet on feed consumption was observed (P>0.05). Overall, results from the current study demonstrate that Met supplementation is a novel way to enrich tissues with n-3 FA and Toc in chickens fed flax.

Dietary Long‐chain PUFAs Enrich Porcine Alveolar Macrophages and Alter Prostaglandin E2 Production Following LPS Challenge

The US swine industry experiences severe production and profit losses from respiratory infections despite the wide spread use of vaccines and antibiotics. Long‐chain PUFAs can modulate immune cell function through the production of eicosanoids, such as prostaglandin E2 (PGE2) which is capable of stimulating both inflammation and inflammatory resolution upon infection. The aim of this study was to determine the effects of dietary arachidonic acid (ARA) and eicosapentaenoic acid (EPA) on cultured porcine alveolar macrophages stimulated with LPS. Day‐old pigs (n=60) were fed milk replacer for 21d. Diets contained 0.5% ARA (control), 2.5% ARA or 3.5% EPA of total fatty acids. Alveolar macrophages were isolated via bronchoalveolar lavage, cultured and stimulated with LPS for 24h. Total fatty acids in alveolar macrophages and lung tissue were analyzed via gas chromatography‐mass spectrometry (GC‐MS). Alveolar macrophages were cultured and stimulated with 10ng/mL LPS or unstimulated (control). Concentrations of PGE2 in tissue culture media were measured via competitive enzyme‐linked immunosorbent assay (ELISA) kits. Average body weight and clinical hematology were unaffected by diet treatments (P &gt;0.5). Concentration of ARA (% of fatty acids, w/w) in alveolar macrophages from pigs fed 2.5% ARA had an 82% increase in ARA compared to controls, and the concentration was decreased 21% in pigs fed 3.5% EPA compared to control (P &lt; 0.01). Lung parenchymal tissue showed a similar enrichment pattern; tissue was enriched by 39% in pigs fed 2.5% ARA, while pigs fed the 3.5% EPA diet had a 45% decrease in ARA compared to control (P &lt; 0.002). Media concentration of PGE2 was increased following LPS stimulation of alveolar macrophages. The increase in PGE2 concentration was greater in macrophages enriched in ARA, exceeding that from control cells by 187% and that from EPA‐enriched cells by 191% (P &lt; 0.05). These data demonstrate that dietary supplementation of LC‐PUFAs can effectively alter lung tissue and alveolar macrophage fatty acid composition. Furthermore, these data validate that increased dietary ARA is an effective means to increase eicosanoid production by LPS‐stimulated immune cells.Support or Funding InformationUSDA Animal Health Funds

Effects of fish meal replacement with meat and bone meal using garlic(Allium sativum) powder on growth, feeding, digestive enzymes and apparent digestibility of nutrients and fatty acids in juvenile rainbow trout (Oncorhynchus mykissWalbaum, 1792)

Effects of graded dietary levels of fish meal (FM) replacement with meat and bone meal (MBM) with garlic powder (G) or without garlic powder (WG) garlic powder were investigated on growth, digestive enzymes, apparent digestibility, body composition and fatty acid profile of juvenile rainbow trout (Oncorynchus mykiss; 8.26 ± 1.10 g). A total of eight dietary treatments were evaluated: control with garlic powder (0 MBM+G), 250 MBM+G, 450 MBM+G, and 650 MBM+G (g MBM/kg diet; treatments with garlic powder; G treatments), control without garlic powder (0 MBM), 250 MBM, 450 MBM and 650 MBM (g MBM/kg diet; treatments without garlic powder; WG treatments). Our results demonstrated that increased dietary content of MBM impaired growth and production performance, body composition, digestive enzyme activity, tissue fatty acid profile and overall digestibility. Addition of garlic powder was able to correct fish performance, body composition, enzyme activity and digestibility to some extent. Dietary supply of garlic resulted in increased digestive enzyme activity improving fish performance. The current results indicated that fish fed 650 g MBM/kg feed exhibited impaired growth that could be attributed to reduce digestibility of protein, fat, energy and dry matter, PUFAs and n-3 LC-PUFAs in muscle. We suggest that 450 g FM per kilo feed can be successfully replaced with MBM supplemented with 30 g garlic powder per kilo feed without impairing fish performance and physiology, however distorting tissue fatty acid composition resulting in lesser levels of n-3 LC-PUFAs compared to the 0 MBM+G diet.

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.

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.

Comparison of Muscle and Subcutaneous Tissue Fatty Acid Composition of Bangladeshi Nondescript Deshi Bulls Finished on Pasture Diet

The objective of this study was to characterize and compare the tissue-associated differences in the fatty acid profiles of intramuscular and subcutaneous fat from pasture fed nondescript deshi breed bulls of Bangladesh. The average chemical composition of thelongissimusmuscle was as follows: moisture74.65±0.48%, protein21.55±0.83%, intramuscular fat2.78±0.28%, and ash1.02±0.03%. There was significant evidence that the lipids oflongissimusmuscle from the nondescript deshi bulls had a lower content of saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), and conjugated linoleic acid (CLA) and a higher content of polyunsaturated fatty acids (PUFA) compared to subcutaneous fat. Intramuscular fat also showed the highest PUFA/SFA and∑n-6/∑n-3fatty acids ratios and total n-3 and n-6 PUFAs compared to subcutaneous tissue depots. Overall findings suggest that the meat from pasture fed nondescript deshi breed can be considered as lean meat and healthy for human consumption.

Supplemental defatted microalgae affects egg and tissue fatty acid composition differently in laying hens fed diets containing corn and flaxseed oil

Effects of defatted microalgae (DFA) on fatty acid composition of eggs and tissues of hens have not been well studied. This experiment was to determine how low concentrations of supplemental DFA in the presence or absence of flaxseed oil (FO) altered fatty acid profiles of egg yolk, liver, adipose tissue, and plasma of layers. A total of 60 Shaver Leghorn layer hens (individually caged, 20-wk old) were allotted into 6 groups (n = 10) and fed a corn/soybean meal basal diet containing 0, 3, or 5% DFA and 0 (1.5% corn oil, CO) or 1.5% FO for 6 wk. BW, ADFI, egg production rate, and egg component weights were not affected by any of the dietary treatments at various time points, but egg yolk color was changed (P < 0.05) with increasing concentrations of DFA. The concentration of n-3 fatty acids in egg yolk and plasma were elevated by FO up to 9-fold (P < 0.05) starting at wk 1 or 2, and 39 to 83% (P < 0.05) by DFA. Supplemental DFA improved (P < 0.05) n-6/n-3 fatty acid ratios in egg yolk and plasma from 13 to 23 and 7 to 13, respectively, only in hens fed diets without FO. Fatty acid profiles of liver and adipose tissue (at wk 6) displayed responses to supplemental DFA and FO similar to those of egg yolk or plasma. In conclusion, supplemental 3 or 5% DFA caused moderate enrichments of n-3 fatty acids and decreased the n6/n3 fatty acid ratios of egg yolk and tissues in hens fed diets without FO.

Dietary fish oil replacement by linseed oil: Effect on growth, nutrient utilization, tissue fatty acid composition and desaturase gene expression in silver barb (Puntius gonionotus) fingerlings.

Silver barb (Puntius gonionotus) is considered a promising medium carp species for freshwater aquaculture in Asia. This study in silver barb was carried out to evaluate the effects of total or partial substitution of dietary fish oil (FO) with linseed oil (LO) on growth, nutrient utilization, whole-body composition, muscle and liver fatty acid composition. Fish (12.1±0.4g of initial body weight) were fed for 60days with five experimental iso-proteinous, iso-lipidic and iso-caloric diets in which FO (control diet) was replaced by 33.3%, 50%, 66.7% and 100% LO. Final weight, weight gain, percent weight gain, SGR decreased linearly (p<0.001) with increasing LO levels in the diets. Dietary LO substitution levels did not significantly (p>0.05) affect the feed conversion ratio (FCR), protein efficiency ratio (PER) and whole body proximate composition. Furthermore, enhanced level of LO increased α-linolenic acid (ALA; 18:3n3) and linoleic acid (LA; 18:2n6) and decreased eicosapentaenoic acid (EPA; 20:5n3) and docosahexaenoic acid (DHA; 22:6n3) in muscle and liver. To understand the molecular mechanism of long chain-polyunsaturated fatty acid (LC-PUFA) biosynthesis, we cloned and characterized the fatty acyl Δ6 desaturase (Δ6 fad) cDNA and investigated its expression in various organs/tissues following replacement of FO with LO in the diet. The full-length Δ6 fad cDNA was 2056bp encoding 444 amino acids and was widely expressed in various organs/tissues. Replacement of FO with LO increased the expression of Δ6 fad mRNA in liver, muscle and intestine but no significant difference was found in the brain.

Dietary linseed oil in the maternal diet affects immunoglobulins, tissue fatty acid composition and expression of lipid metabolism-related genes in piglets.

This experiment investigated the effects of supplementing the maternal diet with linseed oil (LSO) and soya bean oil (SBO) on immunoglobulins, the fatty acid composition and hepatic expression of lipid metabolism-related genes in piglets. Multiparous sows (twenty-four per diet) were fed on diets containing a supplement of either SBO or LSO during last week of gestation and lactation. The results indicated that supplementation of maternal diet with LSO could improve the weaning weight of piglets and average daily gain (ADG) (p<0.05). The concentration of immunoglobulin G (IgG) and immunoglobulin A (IgA) was enhanced in sow plasma, colostrum and milk by the addition of LSO (p<0.05). In addition, the concentration of 18: 3n-3 fatty acids was higher in the milk of LSO sows. Meanwhile, maternal supplementation with LSO increased the levels of plasma IgG, IgA and the tissues n-3 polyunsaturated fatty acid (PUFA) in piglets (p<0.05). Correspondingly, the mRNA expression levels of hepatic ∆5-desaturase (D5D) and ∆6-desaturase (D6D) were higher, and fatty acid synthase (FAS) was lower in piglets from LSO-fed sows when compared with that in the SBO group. In conclusion, LSO supplementation of the maternal diet increases immunoglobulins, modifies the fatty acid composition and affects the gene of D5D and D6D expression of piglets.