E (P ), but a clear difference was present between barren and
E (P ), but a clear difference was present in between barren and enriched pens (tail damage score nursery barren ..; enriched ..; P \).Through the finishing phase (weeks) high IGEg pigs had a reduced tail harm score (high ..; low ..; P ), as well as the optimistic effect of enrichment remained (imply tail damage score finishing barren ..; enriched ..; P \).This resulted in an additive impact of IGEg group and straw enrichment on tail damage, with no interactions between these two elements (P ).Consumption of Jute Sacks From week onward a jute sack was attached to the wall of every pen to limit tail biting behaviour (Fig.).There was no interaction between IGEg group and housing situation for the consumption of jute sacks (P ).Discussion We have investigated the behavioural consequences of a single generation of divergent selection for IGEg in pigs in two housing systems.The divergent IGEg groups showed structural variations in biting behaviours directed towards pen mates and towards the physical atmosphere during the finishing phase.This indicates that selection on IGEg could alter a selection of behaviours, and also behaviours not BIBS 39 Technical Information related to group members, such as biting on objects within the atmosphere.This suggests that selection on IGEg doesn’t merely alter social interactions, but rather leads to alterations in an internal state with the animal from which differences in behaviour might arise.Fig.Tail damage score for high IGEg pigs in barren pens, high IGEg pigs in enriched pens, low IGEg pigs in barren pens, and low IGEg pigs in PubMed ID:http://www.ncbi.nlm.nih.gov/pubmed/21310672 enriched pens.Note that the yaxis ranges from to .while tail damage scores from individual pigs may possibly range from top ).In pens with high IGEg pigs these sacks had to be replaced less often than in pens with low IGEg pigs.More than a period of weeks, high IGEg pigs consumed ..jute sacks per pen, whereas low IGEg pigs consumed ..sacks per pen (P ).Pigs inBehav Genet Prospective Underlying Mechanisms The origin of biting behaviour can be discovered in amongst others aggression, aggravation, tension, or maintenance of dominance relationships (Scott ; Marler ; Schr erPetersen and Simonsen).Aggression and competition happen to be related with IGEs in a wide range of taxa (reviewed by Wilson), for example in laying hens (Cheng and Muir), and had been also anticipated to underlie IGEg in pigs (Rodenburg et al).Pigs chosen for higher IGEg did show subtle variations in aggressive behaviour (Camerlink et al), but most biting behaviour was unrelated to aggression.The expression of aggressive and competitive behaviours may possibly, having said that, have been tempered by ad libitum feeding (Camerlink et al).Pigs of higher IGEg were suggested to be greater in establishing dominance relationships (Rodenburg et al.; Canario et al.; Camerlink et al), but this doesn’t clarify the variations in biting on objects.The varying biting behaviours look extra to originate from aggravation or stress.Pigs have a powerful intrinsic will need to root and forage, and when this have to have cannot locate an outlet in the physical atmosphere it might be redirected to group members (e.g.Schr erPetersen and Simonsen).Tail biting, ear biting, and chewing on distraction material may possibly thus have a similar motivational background.These behaviours have also been related to aggravation, anxiety, and fearfulness (Taylor et al.; Zupan et al).Further behavioural and physiological information recommend that high IGEg pigs might be far better capable of handling stressful conditions and are much less fearful (Camerlink et al.; Reimert et al).Simi.
