DEVELOPMENT OF LYMPHOID-CELLS AND THEIR FUNCTION DURING EARLY CALFHOOD IN BUFFALO

Changes in the proportion and function of lymphoid cells was followed in 7 buffalo calves from birth to 3 months of age. The peripheral bloo d (PB) of newborn calves-was characterized by higher mean total number of leukocytes and neutrophils and tower number of lymphocytes as comp ared to that of calves aged 3 days and above. The number of peanut agg lutinin binding cells (presumably T lymphocytes), amongst mononuclear cells (MNC) prepared by density gradient centrifugation, remained almo st constant. The surface immunoglobulin bearing cells (presumably B ly mphocytes) started increasing in their number from day 20 and showed 4 -fold increase by 3 months of age. The blastogenic response of MNC to PHA and Con A was significantly low during first 10 days of life and i ncreased significantly (P<0.05) by 20 days of age. The low responsiven ess was partly due to enhanced levels of corticosteroids in the blood of newborns. The MNCs showed poor blastogenic response to the lipopoly saccharide. The study indicated functional immaturity of T lymphocytes and less number of B cells in buffalo neonates up to 3 weeks of age.