A total number of 216 unsexed one day old Cobb broiler chicks were randomly divided to six dietary treatments with 6 replicated cages of 6 birds each to investigate the effect of grape seed (GS) and medicago sativa seed (MSS) as sources of natural polyphenols compared with Vitamin E (Vit. E) on productive performance, blood parameters and immune response of broiler chickens. The 1st group was fed a basal diet without supplementation (control), while the 2nd, 3rd, 4th, 5th and 6th groups were fed the basal diet supplemented with 200 IU Vit. E, 0.5, 1.0 gm GS powder, 0.5 and 1% MSS / Kg diet, respectively. Results showed that broilers fed basal diet supplemented with natural sources of polyphenols had greater body weight (BW), body weight gain (BWG) and feed intake and better feed conversion ratio (FCR), economical efficiency, production index compared to Vit. E and control groups. All supplementations decreased serum urea, creatinine, AST, ALT, total lipids, triglycerides, cholesterol, LDL and increased T3,T4, glucose, HDL, Alkaline phosphatase (ALP), total antioxidant capacity (TAOC), glutathione peroxidase (GPX), glutathione (GSH), superoxide dismutase (SOD), RBC's count, hemoglobin, packed cell volume (PCV), WBC's, and Lymphocytes, total protein (TP), β and γ-globulin, globulin, IgA, IgM, IgG, Lysozyme activity (LA), Bactericidal activity (BA), Lymphocyte transformation test (LTT), Phagocytic activity (PA), Phagocytic index (PI), interferon-gamma (IFNγ), interleukin-2 (IL2) and interleukin-10 (IL10) compared to control. All supplementations increased percentage of dressing and total edible parts compared with control. Moreover, all supplementations decreased total bacterial count, Salmonella, E.Coli and proteus compared to control.
In conclusion, natural source of polyphenols either grape seed or medicago sativa seeds could be used safely to improve productive performance, economical efficiency and immune response of broiler chickens, but this experience needs to many studies.