Dietary supplementation of Ocimum gratissimum enhances immune response of broiler chickens without affecting growth performance and blood characteristics

In a previous study, Ocimum gratissimum (OG) was found to have a positive effect on the immune capacity in Taiwan country chickens. This paper explores this potential further. A total of 200 one day-old male and female chickens were randomly assigned to a control group, three OG/Basal Diet groups (1 g/kg, 3 g/kg and 5 g/kg), and one Amoxicillin group. Data collected during the experiment indicated that OG supplementation produced no significant difference in growth performance but slight changes in blood characteristics. However, the different intestinal segments showed significant changes in the 3 g/kg and 5 g/kg OG groups. The haemagglutination, haemaglutination inhibition, and phytohaemaglutinin tests revealed that, compared to control, certain OG dosages produced significant increases in these levels (p< 0.05). These results indicate that OG supplementation enhances humoral immune response and cell-mediated immune response even from a considerably low dosage of 0.1%. Taken together, these findings suggest that although OG does not change growth or blood quality, the enhancements humoral and cell-mediated immune response may improve the overall health and therefore reduce mortality broiler chickens.