Yolk Fatty Acid Research Articles

Effects of dietary inclusion of cassava starch-extraction-residue meal on egg production, egg quality, oxidative status, and yolk fatty acid profile in laying ducks

This study was designed to evaluate the effects of different dietary levels of cassava starch extraction residue meal (CReM) on egg production, egg quality, oxidative status, egg yolk fatty acid profile, and hepatic expression of fatty acid metabolism-related genes. In total, 288 Longyan laying ducks aged 21 wk with similar BW were randomly assigned to 4 dietary treatments, each consisting of 6 replicates of 12 birds. The birds were fed a typical corn-soybean meal diet, which contained 0% (control), 5%, 10%, and 15% CReM, mainly replacing wheat bran, and the experiment lasted for 16 wk. The tested CReM levels did not show significant effects on the egg production, nonmarketable egg percentage, egg weight, daily egg mass, and FCR (g feed: g egg), but daily feed intake was reduced with increased CReM level (linear P < 0.001, quadratic P < 0.05). Yolk color increased (linear and quadratic, P < 0.01) with the increase in CReM level, but the Haugh unit, yolk proportion, albumen proportion, shell proportion, eggshell thickness, and eggshell strength were unaffected. Yolk contents of C11:0 and C12:0 (linear, quadratic, P < 0.01) and total saturated fatty acids increased, and the C22:1 level decreased (linear P < 0.01, quadratic P < 0.05) with the increase in CReM level, but the total monounsaturated fatty acids, the individual and total polyunsaturated fatty acids and n−6 and n−3 fatty acids, triglycerides, and total cholesterol in egg yolk were not affected. Hepatic gene expression revealed a significant increase in peroxisome proliferators-activated receptors γ (linear, quadratic, P < 0.001), but the expression of fatty acid synthase, sterol regulatory element binding protein 1 and apolipoprotein A1 genes were unaffected by CReM level. In conclusion, the results of the current study indicated that the CReM could be included up to 15% in laying duck diets without negative effects on the egg-laying rate, egg quality, and oxidative status. Dietary inclusion of CReM increased the yolk content of total saturated fatty acids and SOD activity in the liver.

Effect of chelated source of additional zinc and selenium on performance, yolk fatty acid composition, and oxidative stability in laying hens fed with oxidised oil

ABSTRACT 1. The following study determined whether the effects of the combined addition of zinc amino acid complex (ZA) and selenomethionine (SM) was superior to their single addition in controlling the oxidative stress induced by dietary oxidised fat in laying hens. 2. Two hundred and forty 32-week-old laying hens were divided into the following dietary treatments (each consisting of six replicates of eight birds): 1) a fresh soy oil (FSO) diet; 2) an oxidised soy oil (OSO) diet; 3) an OSO diet plus 20 mg zinc as ZA/kg (OSO+ZA); 4) an OSO diet plus 0.2 mg selenium as SM/kg (OSO+SM); and 5) an OSO diet plus ZA and SM (OSO+ZA+SM). 3. After 10 weeks of feeding hens, feed intake, egg production, and egg mass in the OSO+ZA+SM group were similar to the FSO group but better (P < 0.05) than those in the OSO group. Shell thickness and shell breaking strength were significantly improved by the OSO+ZA and OSO+ZA+SM treatments. 4. Increases in the yolk concentrations of palmitic acid and total saturated fatty acids (SFA), and decreases in yolk linoleic acid, n-6 polyunsaturated fatty acids (PUFA), total PUFA, and PUFA/SFA ratio were induced by dietary oxidised fat which were normalised (P < 0.05) by OSO+SM and OSO+ZA+SM. 5. An increase (P < 0.05) in malondialdehyde and a decrease in 2,2-diphenyl-picrylhydrazyl radical scavenging activity in the yolk, induced by dietary oxidised fat, was significantly improved by all dietary supplementations, but only birds fed the OSO+ZA+SM diet exhibited similar values to those fed FSO. 6. In conclusion, the simultaneous inclusion of organic zinc plus selenium in the oxidised fat diets was beneficial for improving egg-laying performance, yolk fatty acid profile, and oxidative stability, but not for internal egg quality, compared with either zinc or selenium alone in laying hens.

Productive Performance, Egg Quality and Yolk Lipid Oxidation in Laying Hens Fed Diets including Grape Pomace or Grape Extract.

Simple SummaryPhenolic compounds from grape products are known to possess antioxidant activity. Furthermore, grape polyphenols (anthocyanins) could be valorised as natural pigments. However, the dietary use of grape products in laying hen husbandry and its effect on egg quality traits and yolk lipid oxidation have been scarcely studied. In the present research work, egg yolk colour and Haugh units were increased with the intake of grape pomace and extract. Moreover, dietary inclusion of grape pomace at 60 g/kg increased the proportion of polyunsaturated fatty acids in the yolk and improved the yolk lipid oxidative stability during the storage of eggs, whereas no effect was obtained with grape extract. Regarding hen performance, both grape products reduced feed intake, feed conversion ratio and average egg weight, but they did not affect daily egg production and mass. Feeding grape pomace, at 60 g/kg, and grape extract, either at 0.5 or 1.0 g/kg, decreased protein digestibility. In conclusion, the addition of grape products in the diet of laying hens improved the egg quality but reduced feed intake and egg weight. Dietary grape pomace showed higher antioxidant potential in egg yolk than grape extract.An experiment was conducted to assess in laying hens the effect of including grape pomace (GP, at 30 or 60 g/kg) or grape extract (GE, at 0.5 or 1.0 g/kg) on egg production, feed conversion ratio, protein and polyphenol digestibility, egg weight, egg quality, yolk fatty acid profile and oxidative stability of yolk lipids. No differences were detected among diets for egg production (83.8%, on average) or egg mass (56.8 g/d, on average). However, the average egg weight was lower (p = 0.004) for dietary treatments GP 30, GP 60 and GE 0.5 (67.5 g, on average) than for control hens (68.5 g). Accordingly, in hens fed the GP diets the proportion of XL eggs was lower (p = 0.008) than in control hens, while the proportion of M eggs was higher (p < 0.001) in hens fed the diets GP 30, GP 60 and GE 0.5 than in the control group. The dietary inclusion of both GP and GE decreased daily feed intake (120.9 vs. 125.3 g/d, p < 0.001) and the feed conversion ratio (2.09 vs. 2.18, p = 0.01). Feeding GP at 60 g/kg or GE reduced excreta protein digestibility (54.7 vs. 62.8%, p < 0.001), whereas all GP and GE diets showed higher excreta polyphenol digestibility than the control treatment (57.2 vs. 41.0%, p < 0.001). While yolk colour score was increased with all grape diets (8.12 vs. 7.34, p < 0.001), the dietary inclusion of GP, either at 30 or 60 g/kg, and that of GE at 1.0 g/kg increased the Haugh units of the albumen (80.8 vs. 76.4 Haugh units, p = 0.001). Shell thickness remained unaffected by dietary treatments (365.2 μm, on average). When included in the diet at 60 g/kg, GP reduced the proportion of saturated fatty acids in the yolk (31.6 vs. 32.9%, p = 0.001) and that of monounsaturated fatty acids (39.5 vs. 41.4%, p < 0.001), while it increased the percentage of polyunsaturated fatty acids (28.9 vs. 25.7%, p < 0.001). In fresh eggs, no significant differences were found for the malondialdehyde (MDA) concentration (0.146 mg/kg, on average). In stored eggs, the MDA amount was lower in the eggs of the laying hens fed GP at 60 g/kg than in the eggs of the control hens (1.14 vs. 1.64 mg/kg, p = 0.025). In conclusion, the inclusion of grape pomace, either at 30 or 60 g/kg, and grape extract at 1.0 g/kg in the diet of laying hens improved some egg quality traits, but feeding grape pomace resulted in a lower average weight of eggs. Nevertheless, feeding laying hens with diets containing grape pomace resulted in a higher antioxidant potential in egg yolk than dietary inclusion of grape extract.

Effect of hempseed meal on performance, egg quality and egg yolk fatty acids content in laying quails

In this study, the laying performance, external egg quality, egg yolk colour and fatty acids profile of quails (Coturnix coturnix japonica) fed on diets containing hemp seed meal (HSM) were determined. During 8 weeks trial, a total of 150, 10-weeks-old laying quails were used. Five diets were formulated to contain HSM at the level of 0 (control),5, 10, 15, and 20% that represented as 0 HSM, 5 HSM, 10 HSM, 15 HSM and 20 HSM, respectively.The performance parameters were not significantly (P&gt;0.05)influenced by the dietary HSM contents. Eggshell ratio, eggshell breaking strength, egg shape index, egg yolk index and egg yolk colour values were not significantly (P&gt;0.05) influenced by the dietary HSM, whereas eggshell thickness was significantly (P&lt;0.05) affected. The albumen index has been significantly (P&lt;0.05) increased by increasing in the HSM level in the diets. The HSM supplementation to the diets was effective on fatty acid composition and total saturated fatty acids, total mono unsaturated fatty acids and total polyunsaturated fatty acids content of the egg yolk depending on the addition level. In conclusion, HSM can be used to increase egg total monounsaturated fatty acids and especially omega-3 fatty acids without unfavourable effects on the performance and egg quality parameters.

Effect of feeding linseed oil and vitamin a on production performance, egg characteristics and egg yolk fatty acids in laying hens under sub-tropical conditions

In the present study, linseed oil and vitamin A were fed to the laying hens during hot summer months to produce n-3 PUFA-enriched eggs. Two hundred and forty White Leghorn hens were randomly divided into 24 replicates and fed diets, for 12 weeks,2 with 0, 2, 3, or 4% linseed oil in combination with 3000 or 10000 IU vitamin A/kg. The results revealed that the supplementation of linseed oil and vitamin A to the diets did not affect (P>0.05) the production performance and egg characteristics in laying hens. However, body weight and feed intake were decreased (P<0.05) with the increase in dietary linseed oil levels. The serum total cholesterol, triglycerides, blood glucose, egg cholesterol and triglycerides levels were similar (P>0.05) for all dietary treatment groups. However, serum HDL-cholesterol was increased while LDL-cholesterol was decreased in laying hens with the increase in dietary linseed oil supplementation. The total n-6 PUFA and n-6/n-3 PUFA ratio were decreased while the n-3 PUFA were increased linearly (P<0.001) in the egg-yolks by increasing dietary linseed oil level. Vitamin A did not influence (P>0.05) the egg-yolk fatty acid contents. It might be concluded that, the supplementation of linseed oil to the laying hens kept at high environmental temperature is beneficial for the production of n-3 PUFA-enriched eggs without any considerable effects on production performance.

Effects of Oil Source on Egg Quality and Yolk Fatty Acid Profile of Layer Hens

The effects of different supplemental oils on the performance, egg quality, and fatty acid (FA) profiles of eggs produced by 52 week-old Hy-Line laying hens were investigated. A total of two hundred ninety-two laying hens were assigned to three treatments with four replicates each, according to the source of oil supplemented to their diets: corn oil (CO), restaurant spent oil (RO), and a control diet (with soybean oil, SO) using a traditionally used oil in hens’ diets in local conditions. Egg production was not affected by the type of oil fed and did not change during the course of the study. Eggs mean weight were not affected by type of supplemented oil. A similar trend was observed for shell thickness, yolk heights, Haugh units, and albumen heights. The results demonstrated that both fatty acid C8:0 and C12:0, present in RO and SO respectively, do not appear in the egg yolk in any treatment. Incorporated RO significantly reduced (p<0.05) the percentage of unsaturated fatty acid in egg yolk as compared to the SO or CO. Conversely, replacing SO with high quality oil like CO in the feed of laying hens significantly enhanced (p<0.05) egg quality.

Possibilities of Using Chia Oil As an Omega-3 Source in Laying Quail Diets Chia Oil Supplementation on Quails

This study aims to investigate the effects of different levels of chia (Salvia Hispanica L.) seed oil supplementation as omega-3 source to the diets of laying quails on yield performance, egg quality, and egg yolk fatty acid profiles. The study was conducted including 4 treatment groups as follows: C0 (0 g/kg diet), C1 (1 g/kg diet), C2 (2 g/kg diet), and C3 (3 g/kg diet). In the study, 96 female quails at the age of 18 weeks were used and the trial was carried out for 4 weeks. As a result, it was determined that chia seed oil supplementation to the diet was not effective on feed consumption, feed conversion ratio, egg yield, or egg weight of quails, but it was effective on the yolk index of egg quality characteristics (p<0.05). The most important effect of chia seed oil supplementation to the diet was determined to be on the omega-3/omega-6 ratio of egg yolk. Dietary chia seed oil increased the omega-3/omega-6 ratio (p<0.01). It can be stated that increasing the level of omega-3 in the diets, positively affects the polyunsaturated fatty acid (PUFA)/saturated fatty acid (SFA) ratio.

Effect of maize replacement with different triticale levels on layers production performance, egg quality, yolk fatty acid profile and blood parameters

Effect of maize replacement with different triticale levels on layers production performance, egg quality, yolk fatty acid profile and blood parameters

Dietary supplementation Eucommia ulmoides extract at high content served as a feed additive in the hens industry

Since numerous natural components in Eucommia ulmoides belong to phytoestrogen, its effect on hens production deserve more attention. To investigate the potential of E. ulmoides extract used as a feed additive, laying performance, egg quality, yolk cholesterol, yolk fatty acids, yolk fatty, yolk volatile components, albumen amino acids, plasma biochemical parameters, intestinal histology, and gut microbiota of hens (n = 120) were determined between basal diet (A) and dietary supplementation low (B), middle (C), and high (D) level E. ulmoides extract for 11 wk. When compared to A group, 2 percentage points elevation in laying rate was observed of D group. Significant up-regulation of immunoglobulin indexes and down-regulation of lipid related indexes in D group were also found if comparison with A group, suggesting that supplementation E. ulmoides extract at a relative high content benefited in immunity enhancing and blood-fat depressing. Meanwhile, obvious variation in albumen amino acids and yolk volatile compounds were inspected as dietary supplementation E. ulmoides extract, especially in D group, implied that the flavor of egg would change under high-level E. ulmoides extract treatment. Besides, villus height and villus height to crypt depth ratio of duodenum, jejunum, and ileum in D group were also significantly higher than that of in A group, indicating high-level E. ulmoides extract contributed to nutrient adsorption via intestinal histology changing. Moreover, the richness, diversity, and composition of gut microbiota in D group also significantly altered with a comparison of A group. These variation caused gut microbiota in D group major enriched in the KEGG pathway of insulin signing pathway, systemic lupus erythematosus, and bacterial invasion of epithelial cells, which were conducive to egg production elevation via facilitating nutrient adsorption, inflammation relieving, blood lipid amelioration, and insulin resistance alleviation. These results indicated that dietary supplementation E. ulmoides extract at high content could serve as a feed additive in the hens industry.

Egg enrichment with n-3 fatty acids in farmed hens in sub-optimum temperature: A cold-temperament additive mix alleviates adverse effects of stress on performance and health.

At some stage, laying hen farming is likely to be subjected to sub-optimum temperatures (SOTem) due to climate change. While egg enrichment with n-3 fatty acids is a common practice in the poultry industry, in SOTem it has been less investigated. This study tested the effects of egg enrichment through extruded flaxseed (FLX) (180g/kg) alone or along with hulled-soaked barley (H-SB) (170g/kg), namely FLBA, with and without a cold-temperament additive mix (CTA) (25g/kg: 5g/kg flixweed (Descurainia sophia), 10g/kg dried herb-extraction residues from pussy willow (Salix aegyptiaca) and 10g/kg dried lemon (Citrus limon) residue) in two temperatures (20°C and SOTem: 27°C) on egg performance, yolk fatty acids, lipid components, blood biochemistry, serological enzymes, antioxidant and immune system of Hy-Line W-36 53-week-old for 9weeks. Two hundred seventy layers were randomly distributed to nine treatments, resulting in six replicates with five hens. Hens fed flaxseed diets, regardless of temperature or CTA, had higher levels of n-3 fatty acids in yolks than others. Temperature negatively influenced feed intake and egg production. FLX+H27 and FLBA+H27 groups outperformed the other groups regarding cholesterol in yolk (10.1, 10.3mg/g yolk), high-density lipoprotein (HDL) (5.19, 4.93mg/g yolk), total protein (FLX+H27: 6.82mg/dl), HDL in the blood (FLBA+H27:83.8mg/dl), superoxide dismutase (FLBA+H27:90.4U/ml), glutathione reductase (FLBA+H27: 1042.1U/ml), glutathione peroxidase (FLX+H27: 1149.7U/ml) and catalase (FLBA+H27: 12.5U/ml). Total antibody, immunoglobulin G and immunoglobulin M after 42days were significantly higher in chicks fed CTA-added diets (p<0.05). Replacing corn and soya bean meal with H-SB did not negatively change the above-mentioned factors. Our findings collectively suggest that egg enrichment with n-3 fatty acids through dietary FLBA+H27 (180g/kg flaxseed, 170g/kg H-SB, and 25g/kg CTA) in SOtem is suggested without any adverse impacts.

Enriching laying hens eggs by feeding diets with different fatty acid composition and antioxidants

The current study was conducted to evaluate egg quality, egg yolk fatty acids, health-related indices and antioxidants from laying hens' eggs fed different combined vegetable by-products, rich in fatty acids and antioxidants. One hundred twenty 50 weeks-old Tetra SL laying hens were divided into three groups. They were given daily a standard diet (Control, C), a diet containing 9% rapeseed meal with 3% grapeseed meal (T1 diet), or a diet containing 9% flaxseed meal and 3% sea buckthorn meal (T2 diet). Hen production performances, egg quality, egg yolk fatty acids total polyphenols content and antioxidant capacity were determined. The T1 diet significantly reduced the egg yolk content of palmitic acid from 76.615 mg (C) to 46.843 mg (T1) and that of oleic acid from 788.13 mg (C) to 682.83 mg (T1). Feeding flaxseed and sea buckthorn meals significantly increased the egg yolk content of α-linolenic acid in T2 yolks (35.297 mg) compared with C yolks (4.752 mg) and that of docosahexaenoic acid (DHA) from 16.282 mg (C) to 74.918 mg (T2). The atherogenicity indices (AI) were not significantly affected, whereas the thrombogenicity indices (TI) decreased significantly (p < 0.0007) from 0.72 (C) to 0.60 (T1) and 0.66 (T2), respectively. Adding this combination of meals to the hens' diets, increased the total polyphenol content and antioxidant capacity in T1 and T2 eggs compared to C eggs. The significant enrichment of eggs with n-3 fatty acids and antioxidant capacity, as well on the health-related indices especially from T2 eggs, represents a potential functional feed ingredient in poultry feeding, to obtain eggs as functional food.

Enriching table eggs with omega-3 fatty acids by using ground flaxseed or a combination of flax cake and flaxseed oil in the diet of laying hens

The purpose of the study was to investigate the potential of feeding laying hens with ground flax, a combination of flax cake and flax oil in the production of eggs enriched with omega-3 fatty acids. The experiment was set up using 192 laying hens divided into 4 groups: the control group; a group fed with flaxseed cake (10%) + flaxseed oil (2%); a group fed with 5% ground flax, and a group fed with 10% ground flax. Each group had 8 cages housing 6 laying hens, that is, a total of 48 laying hens per group. The Haugh unit values, fat content, Thiobarbituric acid reactive substances (TBARS) values, yolk color parameters and yolk fat content were measured at the end of 5th and 10th weeks of the trial. The results of this study showed that omega-3 enriched dietary treatments had an impact on the results obtained for the amount of total fat in the yolk, and the results of the TBARS test. The results presented show that the average amounts of alpha linoleic (ALA) and docosahexaenoic (DHA) fatty acids in egg yolk were influenced by the nutritional treatments, i.e. the laying hens that were fed with mixtures enriched with 5% and 10% ground flaxseed, as well as 10% flaxseed cake + 2% flaxseed oil, had significantly (P&lt;0.05) higher amounts of ALA and DHA in their egg yolk compared to the laying hens in the control group.

The Use of Different Fat Sources on Performance, Egg Quality and Egg Yolk Fatty Acids Content in Laying Quails

In this study, the performance, egg quality, egg yolk colour and fatty acids profile of quails fed on diets containing different fat sources were determined. During 8 weeks trial, a total of 75, 10-weeks-old laying quails were used. Three diets were formulated to contain soybean oil (SBO), sunflower oil (SFO) and hempseed oil (HSO), respectively. The performance parameters were not significantly influenced by the dietary different oil sources. Eggshell ratio, eggshell thickness, eggshell breaking strength, egg shape index, egg yolk index, albumen index and egg yolk colour values (except a*) were not influenced by the different dietary oil sources. The a* value was significantly affected and the highest a* value was the HSO of group. The different oil sources supplementation to the diets was effective on fatty acid composition of the egg yolk. The highest value in terms of α-linolenic acid, total polyunsaturated fatty acids and total n-3 fatty acids were found in the diet fed group with HSO added. As a result; supplementation of different sources of oil to quail diets without negatively affecting performance and egg quality can be used to change the egg yolk fatty acid composition. Hempseed oil may increase the amount of total polyunsaturated fatty acids and total n-3 fatty acid content of egg yolk.

Natural variation in yolk fatty acids, but not androgens, predicts offspring fitness in a wild bird

BackgroundIn egg-laying animals, mothers can influence the developmental environment and thus the phenotype of their offspring by secreting various substances into the egg yolk. In birds, recent studies have demonstrated that different yolk substances can interactively affect offspring phenotype, but the implications of such effects for offspring fitness and phenotype in natural populations have remained unclear. We measured natural variation in the content of 31 yolk components known to shape offspring phenotypes including steroid hormones, antioxidants and fatty acids in eggs of free-living great tits (Parus major) during two breeding seasons. We tested for relationships between yolk component groupings and offspring fitness and phenotypes.ResultsVariation in hatchling and fledgling numbers was primarily explained by yolk fatty acids (including saturated, mono- and polyunsaturated fatty acids) - but not by androgen hormones and carotenoids, components previously considered to be major determinants of offspring phenotype. Fatty acids were also better predictors of variation in nestling oxidative status and size than androgens and carotenoids.ConclusionsOur results suggest that fatty acids are important yolk substances that contribute to shaping offspring fitness and phenotype in free-living populations. Since polyunsaturated fatty acids cannot be produced de novo by the mother, but have to be obtained from the diet, these findings highlight potential mechanisms (e.g., weather, habitat quality, foraging ability) through which environmental variation may shape maternal effects and consequences for offspring. Our study represents an important first step towards unraveling interactive effects of multiple yolk substances on offspring fitness and phenotypes in free-living populations. It provides the basis for future experiments that will establish the pathways by which yolk components, singly and/or interactively, mediate maternal effects in natural populations.

Effects of Dietary Addition of Linseed Oil on the Content of Polyunsaturated Fatty Acids in Egg Yolk of Gallus domestiaus

In order to study the effect of dietary supplement of linseed oil on polyunsaturated fatty acids (PUFAs) in egg yolk of Gallus domestiaus, total 160 healthy Gallus domestiaus of 26-week old were randomly selected and divided into 4 groups, each of which included 40 chickens fed outdoors with an area of 63 m2 and free food and drinking water. The control group (CK) was fed the basic diet, and the experimental group was added 1, 3 and 5% of linseed oil in the fundamentals of diet (experimental group 1, 2 and 3, abbreviated as P1, P2, P3), respectively. The content of PUFA and the value of n-6 PUFA and n-3 PUFA in egg yolk were determined by gas chromatography with 24 eggs randomly selected in each group after 10th, 25th and 40th days of the commence of the experiment. We found that the levels of α-linolenic acid (C18:3n3, ALA) and docosahexaenoic acid (C22:6n3, DHA) in egg yolk were clearly higher than the CK when 3% linseed oil or 5% linseed oil were added in the diet during the three experiment periods, in which the contents of linoleic Acid (18:2n6c, LA) and arachidonic acid (C20:4n6, ARA) in egg yolk differ little between P1, P2 and P3 and the CK while the value of n-6 PUFA and n-3 PUFA in egg yolk of the P2 and P3 groups decreased significantly. The comprehensive comparisons suggested that the content of C18:3n3 and C22:6n3 in egg yolk could be clearly increased in the P2 while the value of n-6 PUFA and n-3 PUFA decreased. This study provides theoretical basis for the production of functional eggs enriched with C22:6n3 and C18:3n3.

Effect of supplementation of red beetroot powder in quail diets

This study aims to determine the effects of different levels of supplements (0, 0.5, 1.0 and 1.5%) of red beetroot (B. vulgaris var. rubra L.) powder in the diets of laying quails on productive traits, egg quality, some blood parameters, yolk fatty acid profiles and cholesterol levels. A total of 112, 12-week-old female quails were used in the 4-week study. While the red beetroot powder (RBP) significantly affected egg yield, it was not effective on daily feed intake (DFI), feed conversion ratio (FCR) and egg weight (EW). Among the blood parameters, there were significant differences in terms of the triglyceride (TG), Ca and Na values among the trial groups. In terms of the egg yolk fatty acid profiles, there were significant differences among the palmitic acid and linolenic acid levels of the groups. The results obtained in terms of the egg yolk cholesterol levels showed that the RBP did not significantly affect the cholesterol levels. Consequently, considering its positive effects on some parameters like egg yield, egg yolk colour and palmitic and linolenic acid values, it may be recommended to add RBP to the diets of quails by up to 1%.

Laying Performance, Egg Quality Characteristics, and Egg Yolk Fatty Acids Profile in Layer Hens Housed with Free Access to Chicory- and/or White Clover-Vegetated or Non-Vegetated Areas.

Simple SummaryOutdoor-based systems can improve the product quantity and quality in laying hens. This study investigated the laying performance and several egg quality characteristics in layer hens fed on a conventional diet with free access to a soil area (control, C), a chicory (CI)- or white clover (TR)-vegetated area, or a CI and TR mixture (MIX)-vegetated area. The C hens consumed more concentrate feed, without affecting the laying rate, than did TR and MIX hens. Herbage intake (HI) of the TR and MIX hens was higher than that of the CI birds. The C hens produced eggs with thicker shells than the CI, TR, and MIX hens. The decrease in the feed intake and the improvement in fatty acid (FA) profiles of the egg yolk was related to the HI. Concerning the TR and MIX vegetation, the FA composition of herbage contributed to the production of eggs with preferred FA attributes, such as polyunsaturated FAs and a favourable n-6 to n-3 ratio.This study investigated the laying performance, egg quality, and egg yolk fatty acids (FAs) and cholesterol content in layer hens housed with free access to chicory- and/or white clover-vegetated areas. During a 16-week study, 400 Lohmann Brown hens (32 weeks old) housed with free outdoor access were allocated randomly into four groups, each with four replicates of 25 hens. Control hens were fed a conventional diet with free access to a soil area (C), whereas other hens were fed on a conventional diet with free access to a chicory (CI)- or white clover (TR)-vegetated area or a CI and TR mixture (MIX)-vegetated area. The C hens consumed more concentrate feed (p = 0.018) than the TR and MIX hens, which had a higher herbage intake than the CI birds (p < 0.001). The C hens produced eggs with a thicker shell than those in the other treatment groups (p = 0.013). Compared with C, the saturated FAs of egg yolk decreased for MIX (p = 0.010). The polyunsaturated FAs were higher in the MIX eggs than in the C and TR eggs (p < 0.001). Although FAs were distributed in all quadrants of the principal component analysis (PCA), three main FA profiles could be identified based on the loadings of natural groupings in the PC2 versus PC1 plot. The present study shows clear evidence for the contribution of herbage to the hen diet without affecting laying performance. In addition, the FA composition of the CI and MIX vegetation contributed to the production of eggs with preferred FA attributes, such as polyunsaturated FAs and a favourable n-6 to n-3 ratio.

Effects of Linseed Meal and Carotenoids from Different Sources on Egg Characteristics, Yolk Fatty Acid and Carotenoid Profile and Lipid Peroxidation.

The present study aimed to evaluate the effect of supplementing the diet of laying hens with linseed meal and carotenoids from different sources on egg characteristics, yolk fatty acid and carotenoid profile, and lipid peroxidation. A 4-week experiment was conducted on 168 Lohmann Brown layers (43 weeks of age), assigned to four dietary treatments (42 hens/group; 21 replicate/groups with 2 birds/pen) consisting of a control diet (C) and three diets simultaneously supplemented with 6% linseed meal and 2% dried kapia pepper (E1), 2% dried sea buckthorn pomace (E2) and 2% dried carrot (E3). Every 2 weeks, 18 eggs/group/period were collected randomly from each group and used to determine the egg quality and nutritional parameters. The results showed that dietary linseed meal and carotenoids sources improved egg color, carotenoids’ accumulation in egg yolk and fatty acid profile, especially the n-3 PUFA content. Dietary carotenoids supplementation reduced, n-6/n-3 ratio, cholesterol content of the egg yolk and improved yolk pH, egg thickness and yolk oxidative stability. In conclusion, the use of these sources of carotenoids in the linseed meal enriched diets could be an effective way to improve the nutritional properties of the eggs without affecting their quality and consumer’s safety.

Comparison of Performance, Egg Quality, and Yolk Fatty Acid Profile in Two Turkish Genotypes (Atak-S and Atabey) in a Free-Range System.

Simple SummaryIn recent years, consumers have shown increased interest in healthy and safe food produced under improved animal welfare standards. Therefore, production systems proving outdoor access have gained popularity, increasing the need for knowledge on genotypes suitable for free-range systems. This study aimed to investigate the suitability of two Turkish layer genotypes, Atak-S (brown) and Atabey (white), in a free-range system. We evaluated laying performance, egg quality parameters, and yolk fatty acid profile. The egg production was higher in Atabey than Atak-S, whereas the eggs from Atak-S hens tended to be heavier and had a stronger shell structure than eggs from Atabey hens. Furthermore, eggs from Atabey hens had improved egg yolk and albumen content compared to eggs from Atak-S hens. The total saturated fatty acid content in yolk was higher in Atabey eggs than in Atak-S eggs at 56 weeks of age, whereas a higher yolk color score was observed in Atak-S eggs than in Atabey eggs. Our results could help free-range egg producers to improve production, as well as satisfy consumer demands regarding egg quality in organic production.Consumer interest in buying eggs from animal welfare-friendly systems with outdoor access is increasing, leading to an increase in the need for knowledge on genotypes suitable for free-range systems. Two Turkish laying hen genotypes, Atak-S (brown, n = 210) and Atabey (white, n = 210), were reared in a free-range system from 19–72 weeks of age, and their suitability for the system was assessed based on laying performance, egg quality, and yolk fatty acid profile. Mean hen-day and hen-housed egg production were found to be higher in Atabey than Atak-S (p < 0.01). The brown eggs from Atak-S hens tended to be heavier than the white eggs from Atabey hens (p < 0.01). Brown eggs obtained from Atak-S hens had a stronger shell structure (p < 0.01), while white eggs from Atabey hens had higher mean yolk index, albumen index, and Haugh unit than brown eggs (p < 0.05). At 56 weeks of age, total saturated fatty acid content in yolk was higher in white eggs than in brown eggs (p < 0.01). These findings related to genotype could help free-range egg producers in their choices for more profitable production and for meeting consumer demands on egg quality and egg yolk fatty acid levels.

Transfer of Lauric and Myristic Acid from Black Soldier Fly Larval Lipids to Egg Yolk Lipids of Hens Is Low.

Implementing insects, such as the black soldier fly larvae (BSFL), as animal feed commonly includes the previous removal of substantial amounts of fat. This fat may represent an as yet underutilized energy source for livestock. However, transfer of lauric and myristic acid, prevalent in BSFL fat and undesired in human nutrition, into animal-source foods like eggs may limit its implementation. To quantify this, a laying hen experiment was performed comprising five different diets (10 hens/diet). These were a control diet with soybean oil and meal and a second diet with soybean oil but with partially defatted BSFL meal as protein source. The other three diets were based on different combinations of partially defatted BSFL meal and fat obtained by two different production methods. Lauric acid made up half of the BSFL fat from both origins. Both BSFL fats also contained substantial amounts of myristic and palmitic acid. However, in the insect-based diets, the net transfer from diet to egg yolk was less than 1% for lauric acid, whereas the net transfer for myristic and palmitic acid was about 30% and 100%, respectively. The net transfer did not vary between BSFL originating from production on different larval feeding substrates. The results illustrate that hens are able to metabolize or elongate very large proportions of ingested lauric acid and myristic acid, which are predominant in the BSFL lipids (together accounting for as much as 37 mol%), such that they collectively account for less than 3.5mol% of egg yolk fatty acids.