Effect of Cocoa and Thyme Powder Alone or in Combination on Humoral Immunity and Serum Biochemical Metabolites of Broiler Chicks

Majid Toghyani, Mehdi Toghyani, Mohammad Mohammadrezaei, Abasali Gheisari, Sayed Ali Tabeidian, Gholamreza Ghalamkari

Abstract

This experiment was conducted to evaluate the effect of cocoa and thyme powder separately or in combination on serum biochemical parameters and humoral immune responses in broiler chicks. Two hundred and forty day-old broiler chicks (Ross 308) were randomly assigned to four treatments with four replicates of 15 chicks based on a completely randomized design. The dietary treatments included the basal diet as control, supplemented groups receiving 3 g/kg cocoa powder, 5 g/kg thyme powder and 2+ 3 g/kg a combination of cocoa and thyme added to the basal diet. Blood samples were taken at 28 d to quantify antibody titer production against Newcastle and Influenza viruses and SRBC. Serum biochemical metabolites and leucocyte types were determined at 42 d of age. Serum total protein and globulin concentration increased significantly (p< 0.05) in birds fed diets supplemented with a combination of additives. Diet supplementation resulted in a marked reduction of serum total and HDL cholesterol compared to control group (p< 0.05). Dietary treatments did not induce any significant impacts on antibody titer production, heterophil, lymphocyte, monocyte and eosinophil counts, albumin to globulin and heterophil to lymphocyte ratios. In conclusion application of thyme and cocoa powder, particularly their combination in broiler diets has the potential to improve serum biochemical values but failed to have favourable impact on humoral immune responses of the birds.

Keywords: Broiler, Thyme, Cocoa, Serum biochemistry, Antibody titer