Influence of Replacement Time and Rate of Soybean Oil by Flax Oil in the Leghorn Hens’ Diet on Polyunsaturated Fatty Acid Profile in Eggs

Abstract

Abstract:The study was aimed to evaluate the effect of replacement time and rate of soybean oil by flax oil (FO) on polyunsaturated fatty acid (PUFA) profile in egg of laying hens. Two hundred White Leghorn hens with 30 weeks of age were divided into five treatments with four replicates of 10 birds each. Treatments were assigned randomly and consisted of 0.00%, 0.75%, 1.50%, 2.25% and 3.00% FO in commercial corn-soybean meal diets, in which the soybean oil was partially replaced. The experiment was conducted for 90 d. The main research findings were that feed intake, egg production rate, egg weight and feed conversion were not influenced by time and dietary treatment. Fatty acid content was significantly altered (P < 0.05) by FO, showing a progressive increase in egg n-3 fatty acid (especially docosahexaenoic acids (DHA) and eicosapentaenoic acids (EPA)) when FO was added. Levels of EPA and DHA were higher (P < 0.05) in the egg lipids of FO fed hens than those in the control group. However, no significant differences were observed either in egg weight or egg production among groups. The highest incorporation (P < 0.05) of total n-3 fatty acid content in eggs was obtained with 3% FO/kg. This increase was proportional to FO inclusion levels in the diets.