Webster, J. 2005. Animal Welfare: Limping Towards Eden - A Practical Approach to Redressing the Problem of Our Dominion Over the Animals. Blackwell Publishing, Oxford, UK.

When society gives added value to animal welfare and can trust those who work with animals to put this into effect, then those who work with animals can feel a sense of pride. [p 23] Suffering occurs when an animal fails to cope, or has difficulties in coping, with stress (1) because the stress itself is too severe, too complex or too prolonged, or (2) because the animal is prevented from taking the constructive action it feels necessary to relieve the stress. [p. 62-63]. Fear is an emotional response to a perceived threat that acts as a powerful motivator to action designed, where possible, to evade the threat. [p. 69].