Animal-welfare assessment commonly describes an animal at a particular observation point, although the observed state may reflect exposures, adaptations, and incomplete recoveries accumulated over months or years. This article develops an original non-empirical longitudinal framework for interpreting welfare across the animal life course. It integrates prenatal and early-life conditions, maternal and social environments, housing, disease, pain, human contact, transport, production transitions, reproductive and metabolic demands, adaptation, recovery, and end-of-life decisions. The central argument is that neither the number of adverse events nor the animal’s current appearance adequately represents cumulative welfare. Interpretation must also consider exposure intensity and duration, recurrence, temporal clustering, prior vulnerability, positive experience, adaptive response, opportunity for recovery, and the possibility that apparently stable function conceals physiological or behavioural cost. The proposed architecture therefore separates exposure history, current multidomain state, adaptive capacity, recovery trajectory, and future vulnerability. It also distinguishes reversible compromise from persistent or uncertain change and identifies critical transitions at which concurrent demands may exceed available reserve. The framework is intended to organize assessment and research rather than provide a numerical score, diagnostic threshold, or validated prediction rule. Its transferability is constrained by substantial differences among species, production systems, companion-animal contexts, individual animals, measurement methods, and caregiver resources. Prospective longitudinal studies are needed to determine whether the proposed distinctions improve welfare interpretation or decisions beyond repeated cross-sectional assessment.
