Assertion: pig | /r/Causes | necrosed areas
Facets:
Source sentences:
text: It is a behaviour pattern of high-ranking pigs, although other pigs do it; Various stereotypies, which are repeated actions with no goal direction, have been described (Fraser, 1975) in tethered sows when not provided with straw; Snout rubbing, when pigs rub their snouts on the flanks of other pigs causing necrosed areas (Allison, 1976).