Performance of organic entire male pigs from two sire lines under two feeding strategies : Part 1: Growth performance, carcass quality, and injury prevalence

Castration of young male pigs in organic husbandry systems without anaesthesia contradicts animal welfare principles and consumers’ perception of organic animal husbandry practices. On the other hand, fattening of boars can result in undesirable performance, meat and carcass qualities, and aggressive behaviour resulting in injuries. The objective of the present study in organic boar fattening was to test the effect of two terminal sire lines (Duroc vs Piétrain) and two feeding strategies (without vs with 10 % raw potato starch starting from the live weight of 95 kg prior to slaughter) on performance and carcass quality parameters as well as animal welfare.Daily weight gain, feed conversion, dressing rate, carcass lean, and injury prevalence were measured in a total of 280 boars (65 Duroc Control, 73 Duroc Potato starch, 68 Piétrain Control, 74 Piétrain Potato starch). Testing was performed under organic housing and feeding conditions using German Landrace x German Large White sows which were artificially inseminated using Duroc or Pietrain sires, respectively. Statistics are based on ANOVA (proc glm) by SAS 9.4. Concerning performance and carcass quality, the results confirmed the known differences between the terminal sire lines also in organic entire male pigs; Duroc was superior in daily weight gain, while Piétrain was superior in dressing percentage and lean meat content. Feed conversion ratio did not differ between sire lines and the offer of raw potato starch prior to slaughter remained without noteworthy effect on daily feed intake, feed conversion ratio, and carcass quality. Injury prevalence was generally low, thus indicating no concerns of animal welfare when fattening entire male pigs under organic conditions.