Effects of extruded, milled, and whole flaxseed (Linum usitatissimum) on egg performance, lipid components, and fatty acids concentrations in yolk and blood, and antioxidant system of commercial laying hens

A systematic review of potential productivity, egg quality, and animal welfare implications of extended lay cycles in commercial laying hens in Canada

Lay cycle lengths in the Canadian egg industry are currently 50 to 52 wk (68-70 wk of age). In light of increased productivity in commercial laying hens over the last few decades, the much longer lay cycle lengths already implemented in other countries, extending lay cycle lengths in Canada, should be considered with careful attention to potential environmental, economic, and animal welfare implications. However, there is a lack of information in the public domain that provides robust evidence of performance levels and potential trade-offs to support comprehensive consideration of the desirability of extending lay cycles beyond current Canadian norms. Hence, a systematic literature review using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology was undertaken. Data collection focused primarily on information related to feed-, flock management-, and hen genetics/physiology-related interventions that were studied in literature to support extension of lay cycles (review objective 1), and compiling and analyzing productivity, egg quality, and animal welfare outcomes reported at 70 wk of age or beyond (review objective 2). Several feed-related interventions such as high-protein diets, and probiotics supplements, and flock management interventions such split-feeding were found to potentially improve productivity, and especially egg quality, outcomes in the late laying phase. More studies with bigger flock sizes and in commercial lay facilities need to be undertaken before any of these interventions can be definitively recommended for commercial egg production. Under objective 2, productivity was found to be at acceptable levels well beyond 70 wk of age. Performance on most egg quality traits and animal welfare indicators were also at acceptable levels past 70 wk of age but increased variability was observed beyond ∼80 wk of age. There were also inconclusive indications on how hens in caged housing and white laying hens fare relative to hens in noncaged housing and brown-type layers during the late laying phase. Economic data were limited but suggested that lay cycle lengths beyond 90 wk might not generated net economic benefits.

Does supplementing laying hen diets with a herb mixture mitigate the negative impacts of excessive inclusion of extruded flaxseed?

OBJECTIVE

This study investigated the effects of extruded flaxseed with and without herbs mixture on egg performance, yolk fatty acids (FAs), lipid components, blood biochemistry, serological enzymes, antioxidants, and immune system of Hy-Line W-36 hens for nine weeks.

METHODS

Two hundred forty laying hens were randomly distributed to eight treatments, resulting in six replicates with five hens. Graded levels of dietary extruded flaxseed (0, 90, 180, and 270 g/kg) with and without herbs mixture (24 g/kg: garlic, ginger, green tea, and turmeric 6 g/kg each) were designed as treatments.

RESULTS

The two-way analysis of variance indicated that hens fed herbs mixture had a higher value of egg production, yolk high-density lipoprotein (HDL), superoxide dismutase, glutathione peroxidase, and white blood cell and lower contents of yolk cholesterol, glucose, and blood low-density lipoprotein than those fed diets without herb mixtures (p<0.05). The Flx27 (270 g/kg flaxseed) (153.5 g/kg n-3 FAs) and Flx27+H (270 g/kg flaxseed plus 24 g/kg herbs mixture) (150.5 g/kg n-3 FAs) groups were the most promising treatments in terms of yolk n-3 FAs content. In-teraction effect (herbs- flaxseed) for blood cholesterol, HDL, malondialdehyde, glutaredoxin, alanine transaminase, (ALT), aspartate transaminase (AST), haemoglobin and immune parameters was significant (p<0.05). The results showed layers fed herbs mixture (Flx9+H, Flx18+H, and Flx27+H) had a better value of total antibody, immunoglobulin M, immunoglobulin G, ALT, AST, and blood HDL as compared with representative flaxseed levels without herbs.

CONCLUSION

High inclusion levels of extruded flaxseed (270 g/kg) without herbs to enrich eggs with n-3 appears to impair the antioxidant system, immunohematological parameters, and sero-logical enzymes. Interestingly, the herbs mixture supplementation corrected those effects. Therefore, feeding layers with flaxseed-rich diets (270 g/kg) and herbs mixture can be a promising strategy to enrich eggs with n-3 FAs.

Dietary Freeze-Dried Flaxseed and Alfalfa Sprouts as Additional Ingredients to Improve the Bioactive Compounds and Reduce the Cholesterol Content of Hen Eggs

Eggs are a complete food with high-quality proteins; a 2:1 ratio of unsaturated to saturated fatty acid (SFA); and a good amount of minerals, as well as vitamins or antioxidant compounds. Seeds or mature plants were usually added to the feed to improve egg quality. This study aimed to evaluate the effect of alfalfa and flax freeze-dried sprouts supplementation in diets of laying hens on egg oxidative status and key bioactive compounds. Thirty Sassò hens were fed with three different diets: standard, standard + 3% freeze-dried alfalfa sprouts, or flaxseed sprouts. Ten pools of 10 egg yolks per group were collected at 0, 4, and 8 weeks and analyzed. Supplementation with sprouts enriched the phytosterols, phytoestrogens, tocols, carotenes, vitamin D, and n-3 fatty acid contents in the eggs. Cholesterol content was lower in both sprout-supplemented groups, and a decrease in its oxidative products was also observed. It was found that a 3% freeze-dried sprouts supplementation of approximately 56 days improves the egg quality. Further studies are necessary to verify higher supplementing doses and the applicability of this strategy in the commercial egg production chain.

Rosehip (Rosa canina L.) Meal as a Natural Antioxidant on Lipid and Protein Quality and Shelf-Life of Polyunsaturated Fatty Acids Enriched Eggs

Eggs are a common food of animal origin, inexpensive, and rich in bioactive substances with high biological value. Eggs enriched in polyunsaturated fatty acids (PUFA) are extremely desired by the progressive consumer. However, during storage, eggs undergo some physiochemical changes, which decrease their value. In this regard, the effect of dietary rosehip meal and flaxseed meal on hens’ egg quality characteristics, amino acids, fatty acids, health-related indices, antioxidant capacity, total polyphenols content, and shelf life was examined. For this study 120 Tetra SL laying hens, 29 weeks of age, were fed, for 4 weeks, three diets that included control (basal diet—RF0), basal diet + 1.5% rosehip and 7% flaxseed meal (RF1), and basal diet + 3% rosehip and 7% flaxseed meal (RF2). Productive performance of hens were recorded. The content of essential amino acids (EAA), antioxidant amino acids (AAA), and sulfur amino acids (SAA) was higher in RF1 and RF2, compared with RF0. Eggs belonging to the RF1 and RF2 groups had significantly (p < 0.05) higher content of n-3 PUFAs, especially linolenic and docosahexaenoic acids. Total antioxidant capacity and polyphenol content increased in both rosehip supplemented groups, but especially in RF2. Moreover, eggs from RF1 and RF2 groups maintained significantly higher egg quality parameters after storage for 14 and 28 days in the refrigerator (5 °C) and ambient temperature (21 °C), compared with those from the RF0 group. In the Haugh unit, yolk and albumen pH presented better values in RF1 and RF2 eggs compared to the RF0 eggs.

Sustainable Food Systems: The Case of Functional Compounds towards the Development of Clean Label Food Products

The addition of natural components with functional properties in novel food formulations confers one of the main challenges that the modern food industry is called to face. New EU directives and the global turn to circular economy models are also pressing the agro-industrial sector to adopt cradle-to-cradle approaches for their by-products and waste streams. This review aims to present the concept of “sustainable functional compounds”, emphasizing on some main bioactive compounds that could be recovered or biotechnologically produced from renewable resources. Herein, and in view of their efficient and “greener” production and extraction, emerging technologies, together with their possible advantages or drawbacks, are presented and discussed. Μodern examples of novel, clean label food products that are composed of sustainable functional compounds are summarized. Finally, some action plans towards the establishment of sustainable food systems are suggested.

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) (180 g/kg) alone or along with hulled-soaked barley (H-SB) (170 g/kg), namely FLBA, with and without a cold-temperament additive mix (CTA) (25 g/kg: 5 g/kg flixweed (Descurainia sophia), 10 g/kg dried herb-extraction residues from pussy willow (Salix aegyptiaca) and 10 g/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 9 weeks. 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, 10.3 mg/g yolk), high-density lipoprotein (HDL) (5.19, 4.93 mg/g yolk), total protein (FLX + H27: 6.82 mg/dl), HDL in the blood (FLBA + H27:83.8 mg/dl), superoxide dismutase (FLBA + H27:90.4 U/ml), glutathione reductase (FLBA + H27: 1042.1 U/ml), glutathione peroxidase (FLX + H27: 1149.7 U/ml) and catalase (FLBA + H27: 12.5 U/ml). Total antibody, immunoglobulin G and immunoglobulin M after 42 days 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 (180 g/kg flaxseed, 170 g/kg H-SB, and 25 g/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.