The influence of neonatal environment on piglet play behaviour and post-weaning social and cognitive development

Research has shown that the domestic pig is highly playful throughout its development andthat play is an important aspect of social and cognitive development. Therefore, the neona-tal environment is fundamental to successful stimulation of play in neonatal pigs, whichcould have indirect and direct socio-cognitive effects on pigs post-weaning and thereforeinfluence social interactions known to cause welfare concerns (e.g. aggression during mix-ing). This study investigated how play pre- and post-weaning developed in two neonatalenvironments (NE); the conventional farrowing crate (NEC) and a more environmentallycomplex alternative PigSAFE pen (NEP) and to discover whether this had an effect on piglet’cognitive abilities in spontaneous object recognition tests for two retention times (15 and60 min) post-weaning. Hourly focal sampling was used to record play behaviours pre- andpost-weaning in 72 piglets of mixed sex (36 per NE) from a total population of 117 pigletsfrom 12 litters. Out of the 72 piglets, 24 were used in the cognitive spontaneous objectrecognition tests five weeks post-weaning. Linear mixed models showed that NEP pigletsdisplayed play behaviours quicker after birth than NEC piglets: locomotor (F = 7.62(1, 11),P = 0.020); sow interaction (F = 5.27(1, 11), P = 0.045); and social interaction (F = 23.61(1, 11),P < 0.001). NEP piglets played more pre-weaning than NEC piglets (F = 5.06(1, 71), P = 0.051)and despite initial higher levels of aggression at weaning, displayed less chronic aggres-sion post-weaning as indicated by lesion scores of all piglets (F = 27.05(1, 116), P < 0.001). NEwas shown to have a significant effect on the 15 min cognitive retention test; with NEPpiglets spending more time interacting with the novel object than the familiar, comparedto NEC piglets (F = 5.39(1, 23), P = 0.045). There was no NE effect for the 60 min retention test.It was concluded that play is fundamental to successful socio-cognitive development (e.g.aggressive conflicts) and relates to play function theories of training for the unexpected. Itseffect on play behaviours are short-term and highly dependent on present environmentalstimulus, suggesting that any long-term benefits play may have on an animal’s welfare canonly be achieved by regular stimulation throughout its life (e.g. constant enrichment).© 2014 Elsevier B.V. All rights reserved.