Svansbitning hos grisar, arv eller miljö?

Abstract: Tail-biting in pigs is an animal welfare issue and in Sweden during 2002 the producers lost tree million Swedish crowns because of tail biting. This economic loss depends on the pigs which are discarded at slaughter because of tail biting. Tail biting can be separated into two stages, "pre-injury" and "injury". The aim of this study is to investigate if tail biting depends on environment or genetic background.A lot of research on the environments effects on the behaviour of pigs but not so much on the genetic effects has been performed. The frequency of tail biting in pig farms influence among others of environment enrichment, ventilation, gender and breed of the pig. The space the pigs have to access in the pen should not be too large and not to small and have environment enrichment to prevent that the pigs not perform any abnormal behaviour. If the diet isn’t optimal for the pig it can start tail biting because of its loss of satisfaction. But some studies show that the diet doesn’t influence the frequency of tail biting. It’s mostly gilts that perform tail biting and not castrated males, but they often perform more genital-belly nosing. Tail biting has been found to be heritable in Landrace but not in Large White. By improving the environment can the frequency be reduced on pigs who tail bites. Tail biting has a multi-factorial background and probably tail biting depends on both environment and inheritance.