THE COMBINED INFLUENCE OF DIETARY FLAXSEED VARIETY, LEVEL, FORM, AND STORAGE-CONDITIONS ON EGG-PRODUCTION AND COMPOSITION AMONG VITAMIN-E-SUPPLEMENTED HENS

Trial 1 tested the effects of ground vs whole flaxseed at dietary leve ls of 5, 10, or 15% compared to a corn-soybean or fish oil control on egg production of Leghom hens over a period of 8 wk. Dietary flaxseed decreased feed consumption, weight gain, and egg weights compared to t he control diets; however, flaxseed and fish oil significantly improve d egg production (88.9 and 93.0%, respectively) compared to the contro l (83.1%). Incorporation of linolenic acid (C-18:3n-3) into the egg in creased linearly as the level of dietary flaxseed increased (2.31, 4.1 8, or 6.83% of the yolk fatty acids for 5, 10, and 15% flaxseed diets, respectively). In Trial 1, flaxseed and fish oil significantly increa sed percentage white and decreased percentage yolk compared to the con trol treatment but had no effects on egg cholesterol. Trial 2 was a fa ctorial design of varieties of flaxseed (brown vs golden), types (grou nd vs whole), levels of dietary vitamin E (27 vs 50 IU/kg), and feed s torage temperatures (4 vs 21 C) fed to hens for 6 wk. Brown flaxseed s ignificantly increased egg weight and egg production compared to the g olden variety. There was no difference in whole vs ground flaxseed for measured production variables. Vitamin E (50 IU) significantly improv ed egg production (96.1 vs 94.3%) compared to 27 IU. Storage temperatu re of flaxseed did not significantly affect any production variables. In conclusion, dietary flaxseed can be safely added whole to layer die ts up to 15% without any detrimental effects on hen-day egg production . Levels of 10 to 15% flaxseed yield eggs with 4 to 7% yolk n-3 fatty acids, respectively, making these eggs rich sources of n-3 fatty acids .