In vitro immune competence of buffaloes (Bubalus bubalis) of different production potential: Effect of heat stress and cortisol

Abstract

Twelve healthy lactating Murrah buffaloes of similar parity (3rd) between 90 and 120 days of lactation, selected from the herd of National Dairy Research Institute (Karnal, India) and maintained at managemental practices as followed at the Institute they were included in this experiment. The animals were divided into two groups based on their production level in previous lactation. The average milk production level of group 1 and II was 9.3 and 6lit/day, respectively. Blood was collected from these buffaloes on three occasions 10 days apart. The lymphocytes were separated and cultured in RPMI 1640 medium with PHA-P for 24h at 37()C in a humidified CO2 incubator (95 air and 5CO2). The lymphocyte responsiveness was also evaluated in response to the in vivo heat stress and in vitro cortisol. Mitogen-induced stimulation index was not affected by production level (P