comparison of the effect of different levels of scenedesmus sp. microalgae on growth, immune response, carcass traits, and some blood parameters of broiler chickens

A study was conducted to compare the effects of different levels of a suspension of scenedesmus microalgae (sm) on growth, immune response, carcass traits, and some blood parameters of broilers. two hundred 1-d-old broiler chicks were randomly assigned to each of 5 dietary treatments. treatments consisted of: t1 (100% drinking water), t2 (50% drinking water+50% sm), t3 (25% drinking water+75% sm), t4 (100% sm) and t5 [(basal diet (bd) + 2.5 mg virginamycin kg-1 diet)] with 4 replicate cages of 10 birds each. the birds receiving t3 and t4 had higher feed intake compared with the control and antibiotic groups at 1-10 days (p< 0.001). water replacement by 100% sm increased body weight (p< 0.001) and reduced feed conversion ratio (p< 0.05) in broilers. inclusion of 100% sm increased srbc antibody titer in primary and secondary responses compared to that of the control group. (p< 0.05). the birds receiving t4 had lower serum content of triglycerides and cholesterol compared with the control group (p< 0.05). chickens at the t4 group showed higher relative breast weight compared with the control group (p< 0.05). it was concluded that sm at the levels of 75 and 100% can improve growth performance, immune responses, and some blood parameters of broiler chicks.