Behavioural adaptations of livestock to environmental stressors: implications for welfare and productivity

Livestock are frequently exposed to environmental stressors that adversely affect their welfare and productivity. This review examines the behavioural adaptations of livestock to these stressors and their implications for animal welfare and performance. Environmental stressors are classified into three categories: abiotic (e.g. temperature, light), biotic (e.g. parasitism, social competition), and management-related (e.g. housing, stocking density, transportation). These are further grouped into thermal, nutritional, social, and managerial categories, each with physiological and behavioural consequences. For instance, thermal stress impairs thermoregulation and reduces feed intake; nutritional stress arises from feed scarcity or imbalance; social stress triggers aggression; and management stress results from confinement or handling. These stressors compromise immune function, disrupt endocrine balance, and provoke maladaptive behaviours. Behavioural indicators, such as panting, shivering, aggression and vocalization reflect how animals cope with stress. The review explains how behavioural adaptations influence productivity indicators and highlights assessment tools ranging from visual observation to sensor technologies and artificial intelligence. It also outlines welfare-enhancing strategies, including environmental enrichment, behavioural management, and precision livestock farming. Understanding these adaptive responses can inform context-specific welfare strategies. It also highlights the need for integrative frameworks that link behavioural insights with practical interventions, particularly in under-researched systems vulnerable to climate variability and resource constraints.