In order to evaluate the effects of chlorella on broiler performance and immune system, an experiment
was performed by using 80 ROSS 308 male broiler chicks. The experiment was accomplished in
completely randomized design including 5 treatments with 4 replication and 4 observations in each
replicate. The basal diet was based on corn-soybean meal (control) and without any additives. A
graded level of chlorella (0.07, 0.14 and 0.21%) was added to basal diet to formulating diets 2, 3 and 4
respectively. An extra diet (diet 5) was formulate by adding a commercial prebiotic to the basal diet.
Results showed that feed conversion ratio significantly decreased by adding the chlorella and
commercial prebiotic to the basal diet at 42 d of age (p<0.05). chlorella treatment had numerical
increase in response to phitohemoglotenine-P at 35 d. Results of this study showed that chlorella could
improve performance and may increase cell immune response.