Overall welfare assessment of pregnant sow housing systems based on interviews with experts

In interviews with 11 pig experts the main housing systems for pregnant sow s were identified as tethering (T), individual housing in stalls (IS), grou p housing with stalls (GS), trickle feeding or biofix (B), electronic sow f eeding (ESF), and outdoor housing with huts (O). The family pen system (Fam ) was added as a reference system. The experts were asked to give a welfare score for each housing system. The two individual housing-systems (mean scores: T = 1.8; IS = 2.3) scored sig nificantly lower than more intensive indoor group-housing systems (GS = 5.4 ; B = 5.3; ESF = 6.2), and these scored lower than the mon extensive system s (O = 8.0; Fam = 9.1; ANOVA, P < 0.001). Furthermore, T ranked lower than IS in the Sign test (P = 0.008). The most important aspects for welfare assessment were space, substrate, fe eding-related agonism and social parameters such as group size and group st ability. Three different models were constructed to calculate welfare score s from the arguments given by the experts. When represented graphically the results seem comparable to the expert scores, although two of the three mo dels differed significantly from the expert scores using analysis of varian ce. These results indicate that pig experts are able to perform overall wel fare assessment in a rational way that allows modelling and that there is a consensus underlying welfare assessment. These outcomes provide support fo r the further development of a decision support system to assess farm anima l welfare on a scientific basis.