Natural feed additives as immunomodulators in broiler chickens: Effects on leukocyte profiles and phagocytic activity

Antibiotic-free poultry meat manufacturing is becoming increasingly popular, necessitating the development of non-antibiotic options for animal nutrition. This study was conducted to analyze how broiler hematological parameters and immunological response were influenced by the inclusion of lectin and oregano essential oil in the diet. The experiment involved 180 unsexed Cobb broiler chicks (a day old), which were randomly assigned to three treatment groups (60 chicks/group). Group 1, the control group, was fed the basal diet. Group 2 was fed the basal diet supplemented with 150 mg/kg of lectin. The basal diet provided to group 3 was supplemented with Origanum vulgare oil, 150 mg/kg. Six birds from each group were sampled for blood collection on days 6, 20, and 30 for determination of white blood cell count, percentages of heterophils, lymphocytes, monocytes, eosinophils, basophils, as well as phagocytic activity. Additionally, red blood cell count, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, mean corpuscular volume, red blood cell distribution width–coefficient of variation was determined. Results showed that lectin, and Origanum vulgare oil supplementation significantly increased RBCs, WBCs, and lymphocyte percentage in treated birds. Lectin supplementation significantly increased the phagocytic activity in treated birds. Lectin and Origanum vulgare oil have been proved to be an effective natural supplement for improving immune response in broilers.