Flow Cytometric Analysis of T cell Subset in Bursa of Fabricius in Broiler Chicken (Gallus domesticus)

Bursa of Fabricius, the primary lymphoid organ for B-lymphopoiesis in Avian species and is responsible for humoral immunity. Flow cytometric analysis of Bu-1a+ B-cell count and CD3+, CD4+ and CD8+ T-cell count were conducted in bursa of Fabricius of four different age groups of Nandanam broiler chicken viz., day-old, two, four and six weeks. Twelve birds from each age group, from both vaccinated and non-vaccinated groups were utilised. Tissue samples of the bursa were collected aseptically and processed for flow cytometric studies using monoclonal antibodies. Mean Bu-1a+, CD3+ and CD4+ cell count was highest in four week-old birds and lowest in day-old birds, whereas CD8+ cell count was highest in four week-old birds and lowest in six week-old birds in non-vaccinated group. In vaccinated group, Bu-1a+ cell count was highest in two week-old and lowest in six week-old birds. The mean CD3+ and CD4+ cell count was highest in four week-old birds and lowest in two week-old birds, whereas CD8+ cell count was highest in four week-old and lowest in six week-old birds in vaccinated group.