Effect of dried Chlorella vulgaris and Chlorella growth factor on growth performance, meat qualities and humoral immune responses in broiler chickens

This experiment was carried out to investigate the effects of dried chlorella powder (Chlorella vulgaris; DCP) and chlorella growth factor (CGF) on growth performance, serum characteristics, meat qualities and humoral immune responses in broiler chicks. A total of 1050 day-old Ross male broiler chicks were randomly divided into 35 pens (30 chicks/pen) and subjected to one of seven dietary treatments. A non-medicated corn-soybean meal base diet was considered as negative control (NC) and added with either antibiotic (PC), three levels of DCP (NC diets added with 0.05, 0.15 or 0.5 % DCP) or two levels of CGF (NC diets added with 0.05 or 0.15 % CGF). The final body weight and daily weight gain in PC and groups fed diets with 0.15 or 0.5 % DCP were heavier (p < 0.001) than those of NC and CGF-treated groups. Serum total lipid concentrations were lower (p = 0.001) in groups fed diets with 0.5 % DCP and 0.05 or 0.15 % CGF compared with PC group. The levels of serum IgG (p = 0.050) and IgM (p = 0.010) were elevated in chicks fed diets with DCP and CGF compared with the PC or NC group. Meat qualities such as cooking loss, meat color, and pH, of edible meats were not altered by dietary treatments. Collectively, these results indicate that dietary DCP, but not CGF, exerted growth-promoting effect, and both DCP and CGF affected humoral immune response in broiler chicks.