Effects of addition of flaxseed to diets of laying hens on some production characteristics, levels of yolk and serum cholesterol, and fatty acid composition of yolk

This trial was conducted to investigate the effects of the addition of ground flaxseed to the diets of laying hens on performance, on cholesterol levels in blood and yolks, and on fatty acid composition of yolk. In total, 256 laying hens were fed diets containing ground flaxseed at the levels of 0, 5, 10 and 15%. Feed consumption, feed conversion, egg production of hens, egg mass, egg yolk weight, egg and blood cholesterol levels and fatty acid composition of yolk were investigated. The duration of the experiment was 8 weeks. Compared to the control diet (0% flaxseed), diets including flaxseed decreased feed consumption, egg mass and yolk weights, levels of serum and yolk cholesterol. On the other hand, flaxseed improved feed conversion and egg production (87.1%, 91.0% and 87.9%) for 5, 10 and 15% flaxseed diets, respectively, and egg production increased relatively compared to control diet (84.1%). Levels of total Omega-3 fatty acids linearly increased in yolks as the levels of dietary flaxseed increased (1.80%, 7.07%. 8.35% and 12.20% of egg yolk fatty acids for 0, 5, 10 and 15% flaxseed diet, respectively). Producing eggs with a high level of Omega-3 FA and with a lower Omega-6/Omega-3 ratio meets the needs of individuals concerned with health benefits.