Legislative methods for specifying stocking density and consequences for the welfare of finishing pigs

EU Council Directive 91/630/EEC specifies a banded system of increasing space allowance for finishing pigs, which imposes a degree of inflexibility on housing management. The study presented in this paper investigated whether there are measurable differences in welfare when pigs are kept at the minimum stocking densities described by the bands of the regulations (B), compared to those calculated using an equation (E) relating space allowance and live weight; Area (m2)=0.030×Live weight0.67 (kg). Furthermore, the study compared different floor types [fully slatted (F), solid without straw (N) or solid with straw bedding (S)] at these stocking densities. Eighteen groups of 12 pigs were allocated to this 2×3 factorial experiment, between 29 and 110 kg live weight. Data were collected on a range of welfare parameters. No effects of the space allowance treatments or interactive effects between space allowance and floor type were found. S pigs showed higher levels of manipulative behaviours than N pigs (47 vs. 57% of time spent active, N vs. S; P