A 42-d trial was conducted to compare the effects of probiotic, prebiotic and synbiotic sup-plements on hematological parameters and carcass traits of broiler chicks of broiler chickens. A total of 400 one-d-old male broiler chicks were randomly divided into four treatment groups of four replicates (25 birds per replicate) and fed corn-soybean meal diets. The dietary treatments consisted of a basal diet without any feed additive (control diet), a basal diet with added probiotics (CYLACTIN®), a basal diet with added prebiotics (Raftilose®), and a basal diet with added synbiotics (Biomin®IMBO).At42 days, two birds per replicate were slaughtered for determination of carcass and organweights.At 41 days, blood samples (8 samples pertreatment) were taken for measuring hematological analysis.There were no significant effects of dietary treatments on the values of red blood cells, hemoglobin and hematocrit (P>0.05). The highest WBC count was observed in the birds fed diets supplemented with synbiotic compared with other treatments (P<0.05). Lymphocyte (L) count was significantly higher in the birds fed diets supplemented with synbiotic and H:L ratio was significantly lower in the birds fed diets containing probiotic or synbiotic compared with control diet. There were no significant differences among dietary treatments in terms of carcass traits. The results of this study showed that administration of synbiotic supplementation could promote health indicators by improving WBC count and leukocyte profiles compared with control diet.
