YOLK THIOBARBITURIC ACID REACTIVE SUBSTANCES AND N-3 FATTY-ACIDS IN RESPONSE TO WHOLE AND GROUND FLAXSEED

n-3 fatty acid (FA)-enriched shell eggs have been proposed as an economical source for increasing consumption of n-3 FA. As dietary n-3 FA sources vary with respect to fatty acid profile and lipid stability, the comparison of resulting egg products is warranted. This study was designed to determine yolk thiobarbituric acid reactive substances (TEARS) and n-3 FA when hens were fed whole or ground flaxseed. Gold flaxseed (whole or ground) fed at levels of 5 or 15% were compared to a 1.5% menhaden oil or a typical control layer ration. A 5-wk feeding trial was used with 21 hens per treatment. Eggs were collected and FA composition determined during Weeks 4 and 5 of the feeding trial. The TEARS content of yolk was also determined. All flaxseed treatments increased total n-3 FA (C-18:3 + C-20:5 + C-22:6) but marine n-3 FA (C-20:5 + C-22:6) did not increase proportionately with increasing dietary flaxseed. Seed form did not influence n-3 FA deposition at the 5% level of flaxseed; however, ground 15% flaxseed resulted in greater total n-3 FA deposition than whole 15% flaxseed. Yolk TEARS were not different due to diet, indicating that seed form did not influence the oxidative quality of these n-3 FA-rich lipids.