Pigs suffering from injurious behaviours like flank biting and tail biting are more interested to manipulate a novel rope than uninjured control animals

Injurious behaviours in pigs may involve persistent or forceful biting in specific body parts and may result in wounds of the pigs’ tails, ears, flanks and legs. Such behaviours, which may lead to progressive tissue damage, are difficult to counteract. On a commercial farm 22 groups of pigs with wounds on flanks (n = 16) and tails (n = 6) were matched with 22 control groups without wounds. All groups were provided with a novel rope, applied as a ‘tail chew test’. Interaction with the rope was recorded semi-automatically about 45 and 120 minutes after introduction of the rope. Statistical analysis showed significant decrease of interest in the rope over time and significantly elevated interest in the ropes in pens containing wounded animals (median number of pulls per minute in control pens, flank-biting pens and tail-biting pens were 7.8a , 10.2b and 14.3b respectively, where superscripts indicate significance levels (P <0.001). These results suggest that flank biting and tail biting increase exploration and destructibility in pigs. The approach taken is valuable in further understanding strategies to reduce injurious behaviours in pigs and improving pig welfare, e.g. by providing enrichment materials