Fatty acid composition, physicochemical and sensory properties of eggs from laying hens fed diets containing blue lupine seeds

This study was undertaken to determine the effect of partial replacement of soybean meal with 10% and 20% of blue lupine (Lupinus angustifolius) seeds in layer diets on laying performance, the fatty acid profile, physicochemical and sensory properties of eggs. A 20-week study was performed on 150 Lohman Brown hens with 50 birds in each group. Diet supplementation with blue lupine seeds contributed to an increase in the content of neutral detergent fiber (NDF), acid detergent fiber (ADF) and raffinose family oligosaccharides (RFOs) without compromising laying performance. Feed intake was lower (P = 0.004) in groups fed blue lupine seeds. Eggshell weight as a percentage of total egg weight, and eggshell breaking strength were higher in groups fed lupine-supplemented diets (P = 0.002 and P = 0.036, respectively). Eggs from hens fed blue lupine seeds were characterized by lower albumen quality expressed as albumen height (P = 0.001) and Haugh units (P = 0.001). Diet supplementation with blue lupine seeds contributed to an increase in the concentrations of C18:2 n-6 (P = 0.001) and C18:3 n-3 (P = 0.001) fatty acids and total polyunsaturated fatty acids (PUFAs) (P = 0.001) in yolk lipids. Higher dietary inclusion levels of blue lupine increased the levels of C22:6 n-3 fatty acid (P = 0.004) in the egg yolk, thus significantly (P = 0.035) improving the n-6/n-3 PUFA ratio. Dietary treatments had no influence on the sensory properties of eggs, except for yolk color which was most intense (P <= 0.05) in eggs from hens fed 20% blue lupine seeds. Our results indicate that blue lupine seeds can be added to layer diets at 20% without compromising laying performance. Blue lupine seeds improved yolk color and the fatty acid profile of yolk lipids.