Health, growing performance and meat quality of pigs in indoor and outdoor housing--a controlled field trial

The purpose of the study was to compare indoor and outdoor housing of pigs and their influence on animal health, growing performance and meat quality in a controlled field trial: 29 litters (252 piglets) from indoor and 22 litters (221 piglets) from outdoor were separated at weaning. One half of each litter changed to the opposite housing resulting finally in 4 types of housing: Continuous outdoor or indoor raising and combined outdoor-indoor or indoor-outdoor raising. Pigs in continuous resp. predominant outdoor housing showed lower morbidity and mortality during all raising periods, more active behaviour, higher daily weight gain in weaned pigs and in fattening pigs, but higher feed consumption as compared to indoor housed pigs. However, feed conversion did not differ significantly. Due to climatic influences differences in morbidity were partly more significant in summer litters (intestinal infections) or in winter litters (lung infections). Outdoor pigs raised in summer resulted less often in meat classification E (lean meat percentage > 55%), however, meat quality, estimated by pH-measures did not differ significantly. We conclude from our findings that outdoor housing of pigs from birth to slaughtering may be a serious alternative to predominant indoor keeping with regard to general welfare and growing performance.