Problems associated with the interpretation of physiological data in the assessment of animal welfare

Claims about animal welfare based on data regarding the pituitary-adrenocortical axis should be viewed with scepticism because of the lack of consistency between the results of different studies. Occasional sampling of blood does not give an accurate description of the episodic nature of corticosteroid secretion. Too little is known about how chronic stress affects the activity of the pituitary-adrenocortical axis, or whether changes in mean...