Nowadays, animal welfare is one of the main issues on the agenda of animal production and its control must be scientifically standardized and its interpretation protocolized. Both ethological and sanitary research and the control of facilities are beginning to require stress laboratory parameters in order to maximize the reliability of the observation.The present work aims to test the reliability of some laboratorial parameters of stress in two different product systems such as the deep litter system and the conventional confined system with full slat floor, the possible differences and the criteria for interpretation of the results.