Defatted Microalgae-Mediated Enrichment of N-3 Polyunsaturated Fatty Acids in Muscle of Broiler Chicks Was Not Affected By Supranutrition of Vitamin E and(or) Se

Abstract Text:

We previously demonstrated an enrichment of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) in breast and thigh muscles of broiler chicks fed defatted microalgae. This study was to determine if that enrichment affected physical quality of the meat and was enhanced by feeding less corn oil and extra vitamin E/Se. Day-old hatchling Cornish Giant cockerels (total: 216) were divided to six groups (6 replicate cages/treatment and 6 chicks/cage). The treatments included Diet 1(control) = corn-soybean meal based diet containing 4% corn oil, 25 IU vitamin E as dl-alpha-tocopherol/kg, and 0.2 mg Se as sodium selenite/kg, Diet 2 = Diet 1 + 10% defatted Nannochloropsis oceanica (45.1% CP, 3.8% EE), Diet 3 = Diet 2 - 2% corn oil; Diet 4 = Diet 3 + 75 IU vitamin E/kg, Diet 5 = Diet 3 + 0.3 mg Se/kg, and Diet 6= Diet 3 + 75 IU vitamin E and 0.3 mg Se/kg. The experiment lasted for 6 wk. Data were analyzed by one-way ANOVA with Bonferroni's post-hoc comparisons tests or by Student’s t-test (GraphPad Prism 6.0). Diets produced no difference in growth performance of chicks. Feeding Diet 2 enhanced (P < 0.05) concentrations of breast CP (14%), glycine (60%), and serine (70%) at wk 6 compared with the control. Feeding Diet 2 elevated (P < 0.05) DHA and EPA concentrations of both breast and thigh muscles over the control, whereas feeding Diets 3-6 did not further enhance the enrichments. Both breast and thigh muscles were cooked (175^oC oven for 30 min) for texture analysis. Springiness of the thigh muscles was elevated by 23% (P < 0.05) in chicks fed Diet 2 than in those fed Diet 1. Chewiness of the breast muscle was elevated by 41-83% (P < 0.05) in chicks fed Diet 5 than in those fed the other diets. Chewiness of the thigh muscles was elevated by 79% (P < 0.05) in chicks fed Diet 5 than in those fed Diet 1. In conclusion, supplementation of 10% defatted microalgae in the corn-soybean meal basal diet effectively enriched DHA and EPA in breast and thigh muscles, whereas inclusions of extra vitamin E and Se or less corn oil in the diets did not enhance the enrichments. The additional Se, however, improved chewiness of the muscles. (Supported in part by a USDA/DOE Biomass R&D Initiative Grant and a Cornell Hatch Grant).

Keywords: chicken quality; DHA and EPA, microalgae, selenium, vitamin E