Highlights • First demonstration of between litter differences in play behaviour in pigs.• Litter differences in play behaviour appear independent of overall activity levels.• Litter differences in play behaviour associate strongly with post-natal growth.• Pre-natal factors (particularly birth weight and BMI) associate positively with play behaviour.• Pre-weaning play behaviour has potential as an indicator of positive welfare.

中文翻译：

---

断奶前仔猪玩耍行为差异的证据

亮点 • 首次证明猪的玩耍行为的窝间差异。• 玩耍行为的窝间差异似乎与整体活动水平无关。• 玩耍行为的窝间差异与出生后生长密切相关。• 产前因素（特别是出生体重）和 BMI) 与玩耍行为呈正相关。• 断奶前玩耍行为有潜力作为积极福利的指标。