Stress occurs when animals have to make extreme and/or prolonged physiological and behavioural adjustments in order to cope with their environment.
S Situations
T That
R Release
E Emergency
S Signals for
S Survival
Animals can experience three types of stress:
The factors which can cause stress are called stressors, e.g. noise, unfamiliar pen-mates or dogs. Although many animals might be able to tolerate a single stressor for a short period of time, multiple stressors over a long period of time may lead to distress and suffering.

The ability of animals to cope with stress will also depend on:
Some degree of stress is inevitable during transport, the aim must be to keep it to a minimum.