Broiler Tissue Enrichment with Docosahexaenoic Acid (DHA) through Dietary Supplementation with <i>Aurantiochytrium limacinum</i> Algae

Abstract

The omega-3 fatty acid (n-3 FA) content of broiler tissues can be increased through dietary supplementation of hens with n-3 FA-rich microalgae. The aim of this study was to evaluate the effect of three different dietary inclusion levels of a docosahexaenoic acid (DHA)-rich microalgae (AURA) on broiler performance and the enrichment of tissues with n-3 FA. The randomized study was conducted using 352 birds, housed in 32 pens with 11 birds per pen. Pens were randomly assigned to one of four treatments, with each treatment replicated 8 times. The treatments included one unsupplemented control (0%) and three wheat-soya based experimental diets supplemented with AURA at a level of 0.5%, 1.5% and 2.5% for the starter, grower and finisher periods. Birds were weighed on days 0, 10, 24, 35 and 41, and feed intake was recorded per pen. On day 41, five birds per treatment were euthanized and individually weighed. Thigh muscle, breast muscle, liver, kidney and skin samples were taken post-mortem, freeze dried and DHA content quantified, following fat extraction and methylation, by GC-FID (AOAC 996.06 method). Performance and tissue data were analyzed by ANOVA with Dunnett’s (2-sided) post-hoc test to determine the differences between the mean values for each treatment. Dietary supplementation with AURA had no effect on body weight or feed intake during any period of the study. For thigh muscle, kidney and skin the DHA increased linearly (P < 0.05) with increasing level of dietary AURA, whilst there was a quadratic response in uptake of DHA in breast muscle and liver. The study demonstrated the potential of efficiently enriching broiler meat and organs with DHA by feeding AURA.