STRAIN AND AGE EFFECTS ON EGG COMPOSITION FROM HENS FED DIETS RICH INN-3 FATTY-ACIDS

A trial was conducted to study the effects of strain, age, and diet on egg production, egg composition, and yolk fatty acid incorporation. T hree strains (six pens of eight hens per strain), [DeKalb Delta (D); B abcock B 300 (B); and Hy-Line(R) W-36 (H)], were subjected to a 10% fl ax diet + oats from 30 to 50 wk of age. At 50 wk, hens were divided in to two groups and one half were kept on flax + oats diets (three pens) or assigned to a second diet of flax-oats (three pens) to 60 wk of ag e. Eggs were collected at 36 and 58 wk of age for fatty acid and lipid analysis. Strain had an early effect (30 to 50 wk) on egg production with B (85.3) exceeding the other two strains D (81.0) and H (79.1). S train D had greater feed consumption and egg weight than either B or H . Flax-oats increased percentage shell compared to flax + oats. Strain effect was significant for percentage albumin, which was greatest for D (61.2%) vs H (59.5%) and B (59.4%). Strain D had significantly lowe r total and percentage yolk lipids than the other two strains. Strain B eggs had more C-16:0, but less C-18:0 and C-18:1 than D and H. No si gnificant effect of strain on C-18:2, C-18:3, and C-22:6 deposition wa s observed. Percentage C-18:0 and C-18:1 in the yolk was significantly affected by strain, diet, and strain x diet interaction. Dietary flax + oats increased C-18:0 and C-18:1 in all strains except H. A signifi cant diet by strain interaction effect occurred such that C-18:3 incre ased in D yolk but decreased in B yolk when flax + oats were fed. Depo sition of C-18:3 was greater at 58 wk (5.61%) than at 36 wk (2.52%) of age across all strains. Results from these trials indicate that strai n, diet, and age can affect yolk lipids and composition.