The Five Domains Model, developed by David Mellor and Christopher Reid in 1994, is a scientific framework to systematically evaluate animal welfare. This model, in contrast to the Five Freedoms model developed in 1965, goes beyond simply preventing suffering. It emphasizes not only the physical and functional aspects of an animal’s life but also the mental and emotional states that result from conditions, experience and environment. By recognizing these, the Five Domains aim to ensure we provide animals with experiences for a “life worth living”.
The Five Domains
- Nutrition
This domain focuses on providing animals with an adequate, balanced diet and access to clean water. Proper nutrition ensures vitality, supports growth, and prevents malnutrition and failure to thrive. Insufficiency also influences the animal’s mental state, as unmet nutritional needs can lead to sickness, stress and discomfort. - Environment
The environment domain considers the animal’s habitat, including shelter, space, temperature, air quality, substrate and safety. A suitable environment allows animals to avoid discomfort and hazards while enabling natural exploration and engagement with their surroundings. - Health
Health encompasses freedom from disease, injury, and functional impairments. Maintaining good physical health through timely veterinary care, preventive measures, and monitoring ensures animals can thrive and reduces negative experiences such as pain and distress. - Behaviour
This domain addresses the animal’s ability to express natural, species-specific behaviours. Opportunities for social interaction, foraging, play, and other rewarding activities are essential for positive states of mind that systemically affect health. Behavioral expression is closely linked to mental wellbeing, as restrictions can lead to frustration or boredom. - Mental State
The mental state domain integrates the effects of the first four domains on the animal’s emotional experiences. It considers both negative states (e.g., fear, pain, frustration) and positive states (e.g., comfort, curiosity, satisfaction). Ensuring positive mental experiences is central to achieving overall good welfare.
The Five Domains model highlights that minimizing negative experiences alone is insufficient for good welfare. Animals require opportunities for positive experiences, such as meaningful social connections, exploration, and choice. This approach has been widely adopted in farms, zoos, research, and companion animal care to guide welfare assessment, management, and policy.