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SummaryNutrient deposition in eggs is largely dictated by the dietary composition of laying hen feed, particularly in terms of specific fatty acids and antioxidants. In the present study, the nutritional quality of a range of commercially available egg varieties, marketed as omega-3 enriched; corn-fed; free range and standard caged, were assessed by determining fatty acid profiles and antioxidant status. Across each egg variety, significant differences were observed in key fatty acids such as palmitic, oleic, linoleic, alpha-linolenic and docosahexaenoic acid (DHA) (P ≤ 0.05). Egg yolks enriched with a stated dietary source of omega-3 fatty acid DHA were shown to have significantly improved levels of DHA (P ≤ 0.05), approximately 4.5-fold higher than standard caged eggs. Compared with free range, corn fed and caged, eggs from diets enriched with a source of omega-3 were shown to have considerably altered omega-6: omega-3 ratios, amounting to 1.5–2.1 fold reductions. Yolk antioxidant activity was improved for omega-3 enriched eggs, particularly in hexane fractionated samples. The inclusion of omega-3 fatty acids to the diet resulted in eggs with improved DHA contents and antioxidant status, highlighting the importance of poultry diet composition for egg nutritional quality.

Bioindustrial wastewaters, often characterised by high carbon and nitrogen contents, have shown promise as a valuable resource for the cultivation of beneficial microorganisms. The purpose of this study was to assess if Parachlorella kessleri could utilise brewery wastewater (Br WW) for growth and production of metabolites. P. kessleri was cultivated on different concentrations of Br WW over 14 days. Higher concentrations of Br WW led to an approximate two-fold increase in dry cell weight yielding a maximum of 12.3 g DCW/L. High glucose and nitrogen utilisation was associated with high algal biomass yields, with a 97% reduction in glucose achieved in 50% (v/v) Br WW cultures after 14 days. Assessing the benefits to P. kessleri, increases in oleic and α-linoleic acids were seen in 50 and 10% (v/v) Br WW cultures. Concentration of Br WW did not have an impact on the overall antioxidant activities of microalgal cultures, however, it did affect phenolic levels (2.4-fold increase) in 50% (v/v) Br WW cultures. This research demonstrated that P. kessleri did utilise the carbon and nitrogen content in the Br WW for growth and metabolite production, thereby reducing the nutrient load of the Br WW.

The supplementation of Copper (Cu) is essential for the optimum performance of physiological functions, including growth performance and immune function. Cu is usually formulated into animal premixes in the form of inorganic salts, such as sulphates, or organic minerals. Organic minerals are mineral salts that are either complexed or chelated to organic ligands such as proteins, amino acids, and polysaccharides. Cu is often formulated into premixes alongside other essential components such as vitamins, enzymes and synthetic antioxidants, all of which are susceptible to negative interactions with Cu which can detrimentally effect both their stability and activity. The aim of this study was to determine the effect of five different commercially available Cu sources in relation to their effect on the stability of α-tocopherol acetate and on the activity of Butylated Hydroxytoluene (BHT) and three commercially available phytases in vitro. The results determined that Cu source played a significant role in relation to limiting the interactions between Cu and each of the other components in vitro. There were significant differences (p ≤ 0.05), not only, between the inorganic and organic Cu sources but also between some of the individual organic Cu sources in relation to their effect on α-tocopherol acetate, BHT and phytase.

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