Science - September 1, 2009

Smelly ointments stop pigs biting tails

Stockholm tar and antler oil definitely help to stop pigs biting their tails. But you can also avoid using these smelly ointments by giving them plenty of toys instead.

These suggestions came from animal researcher Dr. Marc Bracke who studied the effects of the ointments using a rope test in several pig pens. ‘If you hang a rope in the pen, the pigs start to play with it and gnaw it to bits. They love it.’ When Bracke applied Stockholm tar or antler oil to some of the ropes in his test, he managed to keep the pigs away from these ropes for an average of seventy minutes. Bracke expects the same result if the ointments are applied to pigs’ tails.
Tail-biting is a welfare problem in pig pens. One way to solve it is to amputate their tails, but pigs may still suddenly start gnawing on the remaining stubs or on each other’s ears. ‘If you don’t do anything it can escalate’, says Bracke. Pig farmers use various substances to try to prevent such an escalation, but none have been scientifically tested. It is now established that the smelly and foul-tasting Stockholm tar and antler oil are two ointments which do have temporary effects.
Ideally, the ointments should heal existing wounds as well, but Bracke is unsure of their effectiveness as disinfectants. His next research target is iodine, known to heal wounds and also to reduce tail-biting.
Above all, Bracke stresses that prevention is better than cure. This can be done by showering the pigs with toys. ‘Keep giving them new items to gnaw on: straw, ropes, firewood and stuff like that.’ Bracke will publish his research findings in the journal Animal Welfare.