Effect of breed type, housing and feeding system on performance of growing pigs managed under organic conditions

BACKGROUND: There is a need for information on the performance and carcass quality of pigs under different organic management systems. This study compared Duroc-sircd progeny from three maternal breed types when kept either at pasture or in housing with an outdoor run and offered ad libitum concentrate either alone or with fodder beet or grass/clover silage as additional forage. RESULTS: Liveweight gain, feed intake and the proportion of forages consumed did not differ between genotypes. Carcass fatness of progeny was lowest for a 'modern' genotype (Camborough 12) and highest for a 'traditional' purebred genotype (Saddleback), with a 'crossbred traditional' genotype (Saddleback x Duroc) being intermediate (11.4, 14.3 and 13.4mm P(2) respectively, standard error of mean (SEM) 0.27, P < 0.001). With a cereal-based concentrate available ad libitum, intake of forages was low (<2% of dry matter intake). Although growth rate did not differ between housing systems, daily feed intake was greater at pasture (2.47 vs 2.22 kg meal equivalent, SEM 0.05, P < 0.001), giving poorer feed efficiency (P < 0.01). Pastured animals consumed less additional forage and had a higher killing-out % but similar carcass fatness. CONCLUSION: For organic pig production to be financially sustainable, disadvantages arising from the genotype and/or rearing system chosen need to be offset by a market premium for the pigs produced. (c) 2007 Society of Chemical Industry.