In Animal Behaviour and Welfare Science 3, behavioural theory and the behavioural and physiological responses of animals to stressors related to husbandry, housing, transport and slaughter are explored. This Unit enables students to develop an understanding of applied animal behaviour theory, and the responses of animals to common interventions that arise in the context of interacting with humans, including the domestication of livestock species and the management of wildlife. We introduce a framework for animal welfare assessment, and the principles of animal responses to stress are illustrated with production species as the main examples. An overview of the key behaviour and welfare considerations for performance and companion animals, and wildlife will be provided. Contemporary approaches to the scientific measurement of animal stress and welfare, based on an appropriate selection of scientific disciplines including ethology, psychology, physiology and neuroscience, are assessed with an emphasis on farmed livestock species. Genetic, environmental and evolutionary determinants of pain, stress and fear responses in animals are considered in the light of what is known about cognition and motivation in animals. Methods for assessing and enhancing animal environments and husbandry systems are examined and the impact on animal behaviour and welfare of stockmanship is explored in the context of human-animal interactions. Finally, the design and conduct of scientific experiments are assessed with a focus on animal ethics and current welfare issues.