Aggregating welfare indicators into an operational welfare assessment system: A bottom-up approach

A welfare assessment system should reflect basic considerations concerning the definition of the term 'welfare' and the goal of the welfare assessment . The aggregation of welfare indicators into an operational welfare system is described as a process in which indicators are evaluated and re-evaluate d step by step for their independent welfare relevance, marginal informatio n value and suitability for use in on-farm studies. Relevant indicators are aggregated into a protocol, and finally this protocol is evaluated in term s of relevance as a welfare assessment system. The theory is illustrated by an example: 'Human-animal relationship among loose housed pregnant sows'.