Serum levels of 2-hydroxyestrone and 16-hydroxyestrone. A, 2-OHE1 and 16-OHE1 were analyzed in the serum samples from control and flaxseed-supplemented diet groups, using the 2-hydroxyestrone and 16-hydroxyestrone Estramet double ELISA kit, n=3 for 5%, 10% and 15% diet groups, n=9 for 0% group (0% vs. 15%, P<0.05). B, Ratio of 2-OHE1/16-OHE1 in the serum samples of chickens fed varying doses of flaxseed supplemented diets.