Andersson et al. (2011) looked at European wild boars in enclosed areas and studied the tendency of infanticide in the population. They discovered that the behaviour is normal in the species, and proposed it was the result of evolution. Victim sows did not actively defend their offspring from the sows which were initiating the attack during the study. Andersson et al. (2011) suggested that defence against infanticide is not a strategy that is commonly and inherently utilized by wild boars. Perpetrator sows only attacked litters which were distantly related or those of their daughters or sisters, and the attacking sow did not target the litter of her dam. During the course of their investigation, it was discovered that counter-strategies have evolved to reduce the incidence of infanticide. The strategies that are utilized are synchronized farrowing as well as self-isolation of the sow at farrowing. This may explain the behaviours that sows display in modern farrowing stalls as they are unable to perform innate farrowing activities. Most captive pregnant sows perform some type of abnormal behaviour, mainly bar biting, due to being tethered during gestation which inhibits natural behaviour (Wiepkema, …show more content…
Behaviours which are considered abnormal and vice-like develop when an animal is unable to perform its natural behaviours which are developed through evolution. The housing practices that animals are kept in causes captive animals to become frustrated and display vice behaviours. Domestic swine commonly perform tail biting, bar biting, ear biting and belly nosing, all of which are undesirable for producers of modern day facilities. Many of the behaviours that are displayed in modern production practices are a result of an inability to partake in their genetically ingrained behaviour. By altering housing systems by providing material to root, and increasing space allotment, the behaviour of captive pigs would closely resemble that of the wild boar. This would decrease the incidence of frustration, and thus cause a reduction in the prevalence of abnormal and vice