Abstract
BACKGROUND: The objective of this study was to determine the effects of humate on performance, egg quality and egg yolk fatty acid (FA) composition in laying hens.
RESULTS: Six hundred and thirty White Lohmann layers at 46 weeks of age were assigned randomly to seven groups, each with 18 replicate cages of five hens. Control diet (C) and C supplemented with 0.10 (H1), 0.15 (H2), 0.20 (H3), 0.25 (H4), 0.30 (H5) and 0.35 (H6) wt% humate were offered for 25 weeks. Humate supplementation improved performance variables and egg quality indices including shape index, yolk colour, albumen index, yolk index and Haugh unit, but not specific gravity, shell strength and shell thickness. Average feed intake (g), egg production (%), egg weight (g) and feed efficiency for the groups were 118.9, 87.2, 68.1 and 2.07 (C), 118.8, 87.7, 66.3 and 2.08 (H1), 119.3, 89.8, 66.6 and 2.03 (H2), 119.5, 88.9, 66.9 and 2.05 (H3), 118.3, 86.5, 66.9 and 2.11 (H4), 119.3, 90.6, 66.9 and 2.02 (H5) and 123.6, 88.5, 66.1 and 2.16 (H6) respectively. Palmitoleic acid concentration increased from 4.34% (C) to 7.65% (H5) and stearic acid concentration decreased from 7.39% (C) to 5.39% (H6) of total FA.
CONCLUSION: Dietary humate supplementation improved performance, inner egg quality parameters and egg yolk fatty acid composition. Copyright Β© 2008 Society of Chemical Industry