Dietary marine algae promotes efficient deposition of n-3 fatty acids for the production of enriched shell eggs

Two experiments were conducted to investigate the usefulness of a natural golden marine algae (MA) as a poultry ration supplement for the production of shell eggs rich in n-3 fatty acids (n-3 FA). This MA is unique due to a high concentration of docosahexaenoic acid (DHA; C-22:6n-3) and the absence of other n-3 FA normally present in marine oils such as menhaden oil (MO). In the first experiment, 60 24-wk-old Single Comb White Leghorn (SCWL) hens were divided among four dietary treatments, including a typical corn-soybean control (CON); 1.5% MO, supplying 233 mg eicosapentaenoic acid (EPA) and 155 mg DHA per d; 2.4% MA, supplying 200 mg DHA/d; and 4.8% MA, supplying 400 mg DHA/d. A second experiment using 96 56-wk-old SCWL was conducted using the same diets. In both experiments, eggs were collected weekly for 4 wk for determination of egg production parameters and yolk FA content. Each week, yolk samples were extracted, saponified, methyl estered, and quantified using:gas chromatography. Transient depressions in egg and yolk weights were noted early in Experiment 1 in response to dietary 4.8% MA. Although egg and yolk weights were not affected in Experiment 2, egg production was significantly reduced in the 4.8% MA treatment. Egg production was unaffected due to diet or week in Experiment 1. In both experiments, yolk polyunsaturated profiles were significantly influenced by diet. Dietary n-3 FA supplementation significantly increased yolk total n-3 FA with concomitant reductions in yolk n-6 FA. Although hens fed MO were supplied predominantly EPA, the principal yolk FA deposited was DHA. Marine algae also promoted efficient yolk DHA deposition with the highest yolk DHA concentrations attained in eggs from hens fed 4.8% MA. These data indicate that utilization of MA as a direct source of dietary n-3 FA may provide an efficient alternative to current sources of n-3 FA available for the production of poultry products rich in n-3 FA.