Effects of different dietary algal species on growth performance, meat quality, and intestinal morphology in broilers

This study investigates the effects of incorporating different microalgal species into broiler diets on growth performance, meat characteristics, serum fatty acids profile, and intestinal morphology. Day-old chickens (240 male Ross 308 broilers) were randomly divided into six groups with five replicates each and eight animals per replicate up to day 35 of life. Five different experimental treatments were designed for the trial along with a control group receiving a basic diet (no additional algae). The five different algae diets (A1-A5) each incorporated 1% of the specific algae added on top of the basic diet. The algae included were Arthrospira platensis (A1), three different Chlorella products (different cultivation methods and processing stages; A2-A4), and Schizochytrium limacinum (A5).

The final body weight did not differ between the groups (p = 0.467) and neither did the feed conversion ratio (range: 1.34-1.39). No significant changes among groups were observed in the histopathological parameters of the jejunum and ileum. When it came to serum fatty acids, most of them did not show significant changes among the experimental groups. However, γ-linolenic acid levels were significantly higher in groups A1-A4, which ranged from 2.81 to 3.56 µg/mL, compared to group A5 (1.27 µg/mL). Arachidonic acid levels were also higher in A1-A4 groups (216-257 µg/mL) than in group A5 (124 µg/mL). On the other hand, group A5 had much higher levels of docosahexaenoic acid (117 µg/mL) compared to the control and A1-A4 groups (16.7-18.9 µg/mL). In addition, the quality of breast muscle in birds fed different algae types showed distinct variations. Birds in group A4 had the highest b*-value for their breast muscle (12.1), while groups A3 and A4 displayed the lowest a*-values (1.13 and 1.18, respectively) compared to the control, A1, and A5 groups (2.19, 2.23, and 2.25, respectively). The results indicate that algae supplementation can be a valuable functional feed ingredient enhancing meat quality parameters with no effect on growth performance parameters. Schizochytrium (A5) is particularly effective in enriching broiler with omega-3 fatty acids (docosahexaenoic acid). Future studies should focus on determining optimal inclusion levels and investigating the long-term effects to maximize benefits while controlling costs.