Pigs are naturally curious animals that, despite many years of genetic selection, are still motivated to explore their environment as they would in their natural woodland habitat.
Pigs explore by
- chewing and
- sniffing food and other items.
Hunger is not the only motivation for this behaviour; even ad libitum fed pigs perform exploratory activities. If there is nothing to explore in a pig pen, pigs often redirect their exploratory behaviour towards pen fixtures and penmates, which can lead to tail and ear biting.
It is a legal requirement (EU directive 2008/120/EC) for pig producers to provide pigs at all production stages, including sows, with permanent access to environmental enrichment materials in “a sufficient quantity… to enable proper investigation and manipulation activities”.