ABSTRACT
Pigs are very adaptable animals that can be reared in many different farming systems. In extensive production systems, animals have great behavioural freedom but are subject to relatively uncontrolled environmental challenges relating to climate, biosecurity, and social competition. Intensive production systems allow humans to control these risks to welfare but reduce autonomy and choice for the animal. Economic pressures to minimise housing space and labour demand introduce a range of different physical and behavioural challenges for the pigs, which can impair welfare and result in the expression of detrimental abnormal behaviours. Good management and husbandry are critical to the welfare outcomes in all production systems, which can be assessed by the observation of various animal-based measures of welfare.
