Influence of feeding stearidonic acid (18:4n-3)-enriched soybean oil, as compared to conventional soybean oil, on tissue deposition of very long-chain omega-3 fatty acids in meat-type chickens

Direct Comparison of 18 Carbon n-3 and n-6 Fatty Acids at Equal Levels in an Oil Blend on Tissue Enrichment of Long-Chain Polyunsaturated Fatty Acid in Broiler Chickens

BACKGROUND

Omega-3 (n-3) and omega-6 (n-6) polyunsaturated fatty acids (PUFAs) are of interest because of their health effects. However, most experiments use natural oils and are confounded by PUFA concentrations and other fatty acids (FAs) that impact biosynthesis of the very long-chain derivatives (VLC).

OBJECTIVES

To directly compare the effect of 18 C n-3 or n-6 FA fed at similar rates on their elongation and desaturation to VLC PUFA and their incorporation into tissues.

METHODS

Oil blends that substituted ∼23% points of stearidonic acid (SDA) with alpha-linolenic acid (ALA), gamma-linolenic acid (GLA), or linoleic acid (LA) while minimizing differences in other FA were prepared. COBB500 broilers were fed the oil blends at 1.25% of the diet from day 14-35 age.

RESULTS

There was greater enrichment of VLC PUFA in breast, thigh, liver, and plasma when diets were supplemented with high-SDA and high-GLA oil blends than high-ALA and high-LA oil blends. The efficiency of VLCn-3 PUFA synthesis from SDA and ALA was lower than the efficiency of VLCn-6 PUFA synthesis from GLA and LA, suggesting that the elongation and desaturation enzymes more efficiently utilized n-6 substrates. The efficiency of biotransformation of SDA to VLCn-3 PUFA was greater than that of high-ALA, and synthesis of VLCn-6 PUFA from GLA was higher than that of high-LA in breast, thigh, liver, and plasma. There were minimal effects on tissue-saturated and monounsaturated FA.

CONCLUSIONS

The high-SDA and high-GLA oil blends efficiently enriched tissues with their VLC-PUFA more than high-ALA and high-LA treatments.

A review of recent studies on the enrichment of eggs and poultry meat with omega-3 polyunsaturated fatty acids: novel findings and unanswered questions

Studies from our laboratory over the past decade have yielded new information with regard to the dietary enrichment of eggs and poultry meat with omega-3 (n-3) polyunsaturated fatty acids (PUFA) but have also generated a number of unanswered questions. In this review, we summarize the novel findings from this work, identify knowledge gaps, and offer possible explanations for some perplexing observations. Specifically discussed are: 1) Why feeding laying hens and broilers an oil rich in stearidonic acid (SDA; 18:4 n-3), which theoretically bypasses the putative rate-limiting step in the hepatic n-3 PUFA biosynthetic pathway, does not enrich egg yolks and tissues with very long-chain (VLC; ≥20 C) n-3 PUFA to the same degree as obtained by feeding birds oils rich in preformed VLC n-3 PUFA; 2) Why in hens fed an SDA-rich oil, SDA fails to accumulate in egg yolk but is readily incorporated into adipose tissue; 3) How oils rich in oleic acid (OA; 18:1 n-9), when co-fed with various sources of n-3 PUFA, attenuates egg and tissue n-3 PUFA contents or rescues egg production when co-fed with a level of docosahexaenoic acid (DHA; 22:6 n-3) that causes severe hypotriglyceridemia; and 4) Why the efficiency of VLC n-3 PUFA deposition into eggs and poultry meat is inversely related to the dietary content of α-linolenic acid (ALA; 18:3 n-3), SDA, or DHA.

Effects of Supplementing Sea Buckthorn Leaves (Hippophae rhamnoides L.) and Chromium (III) in Broiler Diet on the Nutritional Quality and Lipid Oxidative Stability of Meat

Nowadays, the consumer trend towards healthier food choices is unquestionable. Meat products enriched with nutrients, such as polyunsaturated fatty acids and antioxidants, are gaining much more interest among consumers. However, products are susceptible to quality deterioration and a short shelf-life of meat through lipid oxidation due to the lack of antioxidants in the meat. In this regard, the efficacy of dietary sea buckthorn leaves (Hippophaë rhamnoides L.) together with Chromium on the nutritional quality of meat and lipid oxidative stability was investigated. An experiment (28 days long) was carried out on 90 Cobb 500 chickens assigned into three treatments: a control treatment based on corn and soybean meal, without Chromium (T0) and two treatments supplemented either with 0.00002% Chromium (T1) or with 0.00002% Chromium and 2% sea buckthorn leaves (T2). Dietary supplementation of SBL and Cr improved the PUFA/MUFA ratio, DHA concentration and decreased the n-6/n-3 ratio compared to the other treatments. Moreover, the breast and thigh meat belonging to T1 and T2 treatments showed a higher concentration of lutein and zeaxanthin, Fe and Zn and expressed a higher antioxidant capacity compared to those from T0. Furthermore, n-6 and n-3 PUFA deposited preferentially in the thigh meat rather than in the breast meat. The results from the study showed that dietary SBL and Cr significantly improved the fatty acid pattern and the oxidative stability of chicken breast meat, lowering the TBARS level after storage. In conclusion, SBL and Cr are promising dietary bioactive compounds with beneficial effects to obtain nutrient-enriched meat products.

Feeding laying hens docosa hexaenoic acid-rich microalgae oil at 40 g/kg diet causes hypotriglyceridemia, depresses egg production, and attenuates expression of key genes affecting hepatic triglyceride synthesis and secretion, but is rescued by dietary co-supplementation of high-oleic sunflower oil

The primary goal of this study was to investigate the effect of feeding White Leghorn hens graded levels of a docosahexaenoic acid (DHA)-rich microalgae oil (MAO) on productive performance and enrichment of eggs with very long-chain (VLC) omega-3 (n-3) polyunsaturated fatty acids (PUFA). Forty-nine-week-old hens (8 per diet) were fed the following diets for 28 d: 1) A corn-soybean meal-based diet with no supplemental oil (CON); 2) CON + 10 g/kg MAO; 3) CON + 20 g/kg MAO; 4) CON + 30 g/kg MAO; 5) CON + 40 g/kg MAO; 6) CON + 40 g/kg MAO + 20 g/kg high-oleic sunflower oil (HOSO); and 7) CON + 40 g/kg MAO + 40 g/kg HOSO. Diets 6 and 7 were included because we previously reported that co-feeding high-oleic acid oils with n-3 PUFA-containing oils attenuated egg yolk n-3 PUFA contents vs. feeding hens the n-3 oils alone. All data were collected on an individual hen basis. Egg VLC n-3 PUFA enrichment plateaued, in terms of statistical significance, at the 30 g/kg MAO level (266 mg/yolk). Hens fed 40 g/kg MAO had greatly attenuated measures of hen performance, marked liver enlargement, an altered ovarian follicle hierarchy, greatly lowered circulating triglyceride levels, and depressed hepatic expression of key genes involved in triglyceride synthesis and secretion. As compared to hens fed 40 g/kg MAO alone, feeding hens 40 g/kg MAO co-supplemented with HOSO (Diets 6 and 7) restored egg production, ovarian morphology, and all other measures of hen productive performance to CON levels, elevated plasma triglyceride levels, prevented liver enlargement, and increased the hepatic expression of key genes involved in triglyceride synthesis and secretion. In conclusion, MAO can greatly enrich hens' eggs with VLC n-3 PUFA, but its recommended dietary inclusion should not exceed 20 g/kg. This would allow for near-maximal yolk VLC n-3 PUFA enrichment without impairing hen productive performance, altering the ovarian follicle hierarchy or, based on the work of others, presumably imparting off-flavors in the egg.

Comparison of Ahiflower oil containing stearidonic acid to a high-alpha-linolenic acid flaxseed oil at two levels on tissue omega-3 enrichment in broilers

Enrichment of broiler meat with very long-chain omega-3 fatty acids (VLCn-3 FA) is of interest because of their beneficial effects on human health. The ability of Ahiflower® (AHI) oil (Buglossoides arvensis), which naturally contains stearidonic acid (SDA), and a high-alpha-linolenic acid (ALA) flaxseed (FLAX) oil to enrich VLCn-3 FA contents in broilers tissues was investigated. Fifty-five Cobb 500 chicks were fed from days 12 to 35 of life either a control (CON) diet that contained 27.9 g/kg soybean oil or AHI or FLAX oils, each individually at 7.5 or 22.5 g/kg of the diet in substitution for soybean oil (all on an as fed basis). Total VLCn-3 FA contents were greater in breast, thigh, liver, adipose tissue, and plasma of all n-3 treatments compared to CON, with the greatest increase observed at the highest level of AHI and FLAX oils (p < 0.001). AHI oil at 7.5 g/kg promoted the most efficient synthesis and deposition of VLCn-3 in broiler tissues measured as deposition of VLCn-3 FA in tissues relative to intake of n3 FA. In conclusion, both ALA and SDA oils increased VLCn-3 FA deposition in tissues, but there were diminishing returns when increasing dietary levels of the oils.

Supplemental dietary oils rich in oleic acid or linoleic acid attenuate egg yolk and tissue n-3 polyunsaturated fatty acid contents in laying hens co-fed oils enriched in either stearidonic acid or α-linolenic acid

We previously reported that when laying hens were fed diets supplemented with oils enriched in α-linolenic acid (ALA) and oleic acid (OA), the deposition of n-3 PUFA in egg yolk was attenuated as compared to feeding hens a diet supplemented with the ALA-rich oil alone. The present work extends those findings to another n-3 PUFA-rich oil (stearidonic acid [SDA]-enriched soybean oil) and two other high-OA oils, suggesting that the effect is not plant oil-specific. Feeding hens a supplemental linoleic acid (LA)-rich oil plus an oil rich in either SDA or ALA also attenuated egg yolk ALA and SDA contents (Experiment 1), or egg yolk and liver ALA contents (Experiment 2), respectively, as compared to feeding the SDA- or ALA-rich oils alone. Future work should focus on the lack of neutrality of OA and LA in relation to n-3 PUFA nutrition.

Dietary source of polyunsaturated fatty acids influences cell cytotoxicity in broiler chickens

The current study aims to investigate the effects of dietary source of n-3 polyunsaturated fatty acids (PUFA) on immune response in broiler chickens, represented by cytotoxic cell activity. A total of 255 one-day-old male Cobb 500 broiler chickens were fed on fish oil (FO)-, flaxseed oil-enriched diets at 50 and 19 g/kg, respectively, in addition to the soybean-based control diet. At slaughter, samples of blood and spleen were harvested from 20 birds/treatment (n = 20). The immune tissues' fatty acid profile was analyzed by gas chromatography, and the cytotoxic cell activity was investigated. The results showed that supplementing broiler chickens with diets rich in n-3 PUFA had a substantial effect on the broiler immune tissues' fatty acid profile. Cytotoxic cell activity was significantly higher in splenocytes and peripheral blood mononuclear cells (PBMCs) from broilers fed flaxseed oil than those provided FO and the soybean control diet. These results suggest that flaxseed oil may be used to enrich chickens with n-3 PUFA and improve the immune status of chicken flocks to resist diseases.

Giblets and abdominal fat of pomegranate seed oil fed chickens as a source of bioactive fatty acids

The aim of present study was to determine whether chickens' (broilers Ross 308, n = 180, sex ratio 1:1) diet modification with different doses of grape or pomegranate seed oil will favourable change fatty acids and cholesterol content in selected giblets (liver and heart) or wastes (adipose tissue). It was also verify whether generated changes would make the giblets and wastes more valuable as dietary components or by-products for food industry. From 22 to 42 day of life, five diets were administered to chickens. Control grower diet (CON) contained 5% of soy oil, whereas in the experimental grower diets part of soy oil (1.5% or 2%) was replaced with specific amount of grape or pomegranate seed oil (GRAP 1.5; GRAP 2.0; POM 1.5; POM 2.0 respectively). Fatty acids and cholesterol content were determined with gas chromatography with flame-ionization detection. Pomegranate seed oil improved fatty acids profile more favourably than grape seed oil, which makes it a valuable additive in chickens' feeding. Abdominal fat of pomegranate seed oil supplemented chickens appeared to be the richest sources of rumenic acid and n3 polyunsaturated fatty acids, which allows to suggest its use in manufacturing of meat products to obtain foodstuffs rich in those essential nutrients. In principal component analysis (PCA), two principal components: PC1 and PC2, which were enough to explain 29.91% of variance of initial variables, allowed to a good separation of chickens fed with both doses of pomegranate seed oil from animals from control and grape seed oil fed groups. Because poultry addresses all nutritional, institutional and consumer requirements, enrichment of giblets in rumenic acid by pomegranate seed oil incorporation into chickens' diet may provide a valuable dietary source of bioactive fatty acids for consumers, especially of low-income countries.

Acyl-lipid desaturases and Vipp1 cooperate in cyanobacteria to produce novel omega-3 PUFA-containing glycolipids

BACKGROUND

Dietary omega-3 (n-3), long chain (LC-, ≥ 20 carbons), polyunsaturated fatty acids (PUFAs) derived largely from marine animal sources protect against inflammatory processes and enhance brain development and function. With the depletion of natural stocks of marine animal sources and an increasing demand for n-3 LC-PUFAs, alternative, sustainable supplies are urgently needed. As a result, n-3 18-carbon and LC-PUFAs are being generated from plant or algal sources, either by engineering new biosynthetic pathways or by augmenting existing systems.

RESULTS

We utilized an engineered plasmid encoding two cyanobacterial acyl-lipid desaturases (DesB and DesD, encoding Δ15 and Δ6 desaturases, respectively) and "vesicle-inducing protein in plastids" (Vipp1) to induce production of stearidonic acid (SDA, 18:4 n-3) at high levels in three strains of cyanobacteria (10, 17 and 27% of total lipids in Anabaena sp. PCC7120, Synechococcus sp. PCC7002, and Leptolyngbya sp. strain BL0902, respectively). Lipidomic analysis revealed that in addition to SDA, the rare anti-inflammatory n-3 LC-PUFA eicosatetraenoic acid (ETA, 20:4 n-3) was synthesized in these engineered strains, and ~ 99% of SDA and ETA was complexed to bioavailable monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG) species. Importantly, novel molecular species containing alpha-linolenic acid (ALA), SDA and/or ETA in both acyl positions of MGDG and DGDG were observed in the engineered Leptolyngbya and Synechococcus strains, suggesting that these could provide a rich source of anti-inflammatory molecules.

CONCLUSIONS

Overall, this technology utilizes solar energy, consumes carbon dioxide, and produces large amounts of nutritionally important n-3 PUFAs and LC-PUFAs. Importantly, it can generate previously undescribed, highly bioavailable, anti-inflammatory galactosyl lipids. This technology could therefore be transformative in protecting ocean fisheries and augmenting the nutritional quality of human and animal food products.

The effect of pomegranate seed oil and grapeseed oil on cis-9, trans-11 CLA (rumenic acid), n-3 and n-6 fatty acids deposition in selected tissues of chickens

The aim of this study was to determine whether diet modification with different doses of grapeseed oil or pomegranate seed oil will improve the nutritive value of poultry meat in terms of n-3 and n-6 fatty acids, as well as rumenic acid (cis-9, trans-11 conjugated linoleic acid) content in tissues diversified in lipid composition and roles in lipid metabolism. To evaluate the influence of applied diet modification comprehensively, two chemometric methods were used. Results of cluster analysis demonstrated that pomegranate seed oil modifies fatty acids profile in the most potent way, mainly by an increase in rumenic acid content. Principal component analysis showed that regardless of type of tissue first principal component is strongly associated with type of deposited fatty acid, while second principal component enables identification of place of deposition-type of tissue. Pomegranate seed oil seems to be a valuable feed additive in chickens' feeding.

Dietary High-Oleic Acid Soybean Oil Dose Dependently Attenuates Egg Yolk Content of n-3 Polyunsaturated Fatty Acids in Laying Hens Fed Supplemental Flaxseed Oil

Chickens can hepatically synthesize eicosapentaenoic acid (20:5 n-3) and docosahexaenoic acid (22:6 n-3) from α-linolenic acid (ALA; 18:3 n-3); however, the process is inefficient and competitively inhibited by dietary linoleic acid (LNA; 18:2 n-6). In the present study, the influence of dietary high-oleic acid (OLA; 18:1 n-9) soybean oil (HOSO) on egg and tissue deposition of ALA and n-3 polyunsaturated fatty acids (PUFA) synthesized from dietary ALA was investigated in laying hens fed a reduced-LNA base diet supplemented with high-ALA flaxseed oil (FLAX). We hypothesized that reducing the dietary level of LNA would promote greater hepatic conversion of ALA to very long-chain (VLC; >20C) n-3 PUFA, while supplemental dietary HOSO would simultaneously further enrich eggs with OLA without influencing egg n-3 PUFA contents. Nine 51-week-old hens each were fed 0, 10, 20, or 40 g HOSO/kg diet for 12 weeks. Within each group, supplemental dietary FLAX was increased every 3 weeks from 0 to 10 to 20 to 40 g/kg diet. Compared to controls, dietary FLAX maximally enriched the total n-3 and VLC n-3 PUFA contents in egg yolk by 9.4-fold and 2.2-fold, respectively, while feeding hens 40 g HOSO/kg diet maximally attenuated the yolk deposition of ALA, VLC n-3 PUFA, and total n-3 PUFA by 37, 15, and 32%, respectively. These results suggest that dietary OLA is not neutral with regard to the overall process by which dietary ALA is absorbed, metabolized, and deposited into egg yolk, either intact or in the form of longer-chain/more unsaturated n-3 PUFA derivatives.

Effect of feeding of prefermented bioproduct containing gamma-linolenic acid and beta-carotene on selected parameters of broiler chicken meat quality

The aim of the work was to evaluate the effect of addition of prefermented bioproduct with a increased content of polyunsaturated fatty acids (especially gamma-linolenic acid) and beta-carotene into commercial feed on the selected qualitative parameters. The chemical composition, the color, the loss of water, the pH and the concentration of lactic acid of the meat of broiler chickens (COBB 500) were monitored. Bioproduct was prepared from corn scrap, which was fermented using the lower filamentous fungus Umbelopsis isabellina CCF2412. The prepared material was mixed into the commercial compound feed intended for broiler chickens at a ratio of 10%, and was fed from the 11th day of age of the chickens until the time of slaughter. The obtained results were compared with the results of control group, which was represented by broiler chickens fed only with a commercial compound feed. Feeding of bioproduct, in terms of chemical composition, affected mainly the fat content in breast and thigh meat, which was lower in the experimental group. Meat color (measured by colorimetric assay) was not affected and differences were significant only at a value a*, which was higher in the experimental group. Statistically significant differences in the water losses of meat were not recorded, but the feeding of bioproduct affected the pH of the meat, and also the concentration of lactic acid and both parameters were higher in the meat of control group.