Prophylactic Anticoccidial Effects of the Methanol Extracts of Ganoderma lucidum, Vernonia amygdalina Leaves and Vitellaria paradoxa Stem Bark: An Investigation of the Cytokine and Immunoglobulin Y Responses in Eimeria tenella-infected Broiler Chickens

This study evaluated the interleukin-6 (IL-6), interferon-gamma (INF-γ), and immunoglobulin Y (IgY) responses in Eimeria tenella-infected broiler chickens pre-administered with the methanol extracts of Ganoderma lucidum, Vernonia amygdalina leaves and Vitellaria paradoxa stem bark. One hundred 1-day-old broiler chicks were obtained, brooded for two weeks, and then randomly divided into 10 groups (A1, B1, C1, D1, A2, B2, C2, D2, E, and F) of 10 birds each. From 14 to 20 days of age (doa), groups A1 and A2 were administered G. lucidum; B1 and B2 V. amygdalina; C1 and C2 V. paradoxa; D1 and D2 Amprolium (100 g/100 L drinking water; while no extract/medication was administered to groups E and F. At 21 doa, groups A2, B2, C2, D2, and E were challenged orally with 104 E. tenella sporulated oocysts. Blood was collected at 14, 21, and 28 doa in labeled plain tubes, and serum was harvested and assayed for IL-10, INF-γ, and IgY levels. Results revealed no significant difference (P > 0.05) in the serum IL-10, INF-γ, and IgY levels in all groups of chickens at 14 and 21 doa. At 28 doa, serum IL-10 level was significantly (P < 0.05) higher in B2 and C2 compared to A2, D2, and E. The levels of INF-γ and IgY were not significantly (P > 0.05) higher in B2 and C2 than in A2, D2, and E. The prophylactic administration of G. lucidum, V. amygdalina leaf, and V. paradoxa stem bark methanolic extracts altered changes in the serum IL-10, INF-γ, and IgY levels induced by E. tenella challenge in the broiler chickens. The mechanisms involved in these cytokines and IgY responses as a result of the prophylactic administration of these extracts require further investigation.