The development of playful behaviour in piglets from birth to weaning in three farrowing environments

Observations of piglet play behaviour were recorded on real time video over 28 days during six periods for 6 h per period per litter (days 1-5, 6-10,11-15, 16-20, 21-25, 26-30), from birth, in three farrowing environments: (i) an adjustable parallel crate (800 mm width) in a 2130 mm X 2105 mm pen; (ii) a round crate (1.85 mm diameter) within a pen (2130 mm x 2105 mm); (iii) a pen (2130 mm X 2105 mm) surrounded on the inside by horizontal metal bars 200 mm above the floor. Eight sows and their litters were observed in each environment. Individual play was recorded as spring (sudden jumping or leaping, 9.6% of observations of play frequency, highest in the round crate), run (8.3% of play, no pen differences) and object play (18.8% of play, highest in the parallel crate). These behaviours all began at 3-5 days of age, and peaked at 21-25 days. Social play, which involved nudging or pushing other animals also began at 3-5 days. Nudging contributed 12.3% of observations of play, this behaviour occurring more frequently in the open pen, while pushing comprised 17.1% of play observations and was greatest in the parallel crate. Play with sow began on days 1-2 with piglets climbing, nudging, or biting the sow. This accounted for 22.6% of observations of play and occurred at higher levels in the round crate and open pen than in the parallel crate. Naso-naso contact of piglets with the sow also began early (days 1-2) and averaged 11.0% of play observations with a higher frequency in the parallel crate. The end to a social play episode was usually separation as piglets ceased their activity and walked away (average 72.2% of observations of play endings). Aggression, where the play developed into a fight, accounted for 27.8% of endings in the parallel crate, only 12.5% in the open pen and 13.4% in the round crate. Rest, where the piglets lay down after play, accounted for an average 9.7% of observations of play endings and was much higher in the parallel crate. This study shows that play behaviour develops rapidly in an intensive farrowing environment, which may indicate that piglet welfare is not compromised. (C) 1997 Elsevier Science B.V.