Abstract
    
A total number of 270 chicks were used to determine the effect of using dietary Sargassum muticum and artificial antioxidants as broiler's feed supplements for enhancing growth efficiency: blood chemistry and lipid oxidation of broiler's meat Thiobarbituric Acid-Reactive Substances (TBARS). All chicks were brooded together at the first 2 days. On the third day, 15 chicks of each replicate (45 for each group)were randomly distributed into 6 experimental treatments:T₁:(Control+) received (23% crude protein) and (19% crude protein). T₂: (control^-): a starter diet (20% crude protein) and grower & finisher diet (16% crude protein).; T₃:T₂ + Butylated hydroxytoluene (BHT) 150 ppmin drinking water; T₄:  T₂ + 0.5% Sargassum powder (50 g/kg feed); T₅:T₂ + 10 mL Sargassum extract/kg feed in drinking water. The results showed that highest (P≤0.05) final body weight (2515.78 g) was recorded withT₄ group (T₂ + 0.5% Sargassum powder (50 g/kg feed). Also, The group fed T₄ diet recorded the highest (P≤0.05) total body weight gain (TG) (2445.02g), and the lowest total feed intake (6373.94g) when compared with control. The best ratio of feed conversion was recorded with birds fed  T₄ diet followed by those fed T₅ and T₆ being 2.7; 2.74 and 2.79, respectively. It can be concluded that the addition of dietary 0.5 % Sargassum powder/kg feed or Sargassum extract up to 15 mL Sargassum extract/kg feed.in drinking water to broiler diets has a positive effect on growth performance, lipid metabolism, immune status, blood chemistry and carcass shelf life.