Social communication during a sow-piglet foraging paradigm.

Offspring may use various sensory modalities to learn from the mother, but this has in pigs received relatively little research attention. The objective of this study was to investigate social cues between sow and piglet during a learning scenario related to foraging. We hypothesized that 1) the sow and piglet make frequent visual, auditory and tactile contact, 2) that their behaviour is related, and 3) that frequent sow-piglet communication translates to health benefits for the offspring. Four-week old piglets (n = 95) were tested individually with their mother (n = 11 sows) in a 3-min foraging paradigm. Two food types were available which were known to the sow but unfamiliar to the piglet. Foraging, social behaviour and vocalisations were recorded. In the test, the sow and piglet interacted frequently, but mostly through visual and auditory contact rather than physical contact. Food-related and social behaviour of the sow positively related to the piglets' behaviour. There was no significant relationship between the weight gain of the litter and the sows' food-related or social behaviour. In conclusion, sows and piglets showed a bidirectional communication in a learning scenario, whereby the sow mainly has a demonstrator role.