Effect of acquisition of improved thermotolerance on the induction of heat shock proteins in broiler chickens

The role of heat shock proteins (HSP) in the protection of cells from heat stress is well established. However, very little is known about their contribution to thermotolerance in the complexity of a whole homeotherm animal. Here we report on the analysis of protein synthesis in lung and heart muscle tissues of broiler chickens following exposure to high ambient temperature. Half of the flock was treated by an early age exposure to heat (conditioning), to improve thermotolerance. In contrast to what has been expected, lower levels of HSP induction was observed in the treated chickens. We suggest that 1) the induction of HSP in the heart and lung tissues of the whole animal correlates with the body temperature and 2) HSP response does not represent a part of the long-term mechanism that is evoked by the early age conditioning.