Effects of prepartum housing environment on abnormal behaviour, the farrowing process, and interactions with circulating oxytocin in sows

Abstract We evaluated the effects on sows of prepartum housing environment on bar-biting (BB) behaviour prior to parturition, farrowing duration from first to tenth piglets, litter size, and circulating oxytocin (OT) concentrations during birth of the first five piglets. A total of 35 sows, approximately seven days before the expected parturition date, were housed in: (1) CRATE ( N  = 11): the farrowing crate closed (210 × 80 cm), with provision of a bucketful of sawdust, (2) PEN ( N  = 12): the farrowing crate opened, with provision of a bucketful of sawdust, and (3) NEST ( N  = 12): the farrowing crate opened, with provision of abundant nesting materials. All sows were crated without additional supply of nesting materials when parturition started. Plasma samples from farrowing sows were collected via an indwelling catheter at 0, 2, and 4 min, after delivery of each of the first five piglets to assess circulating OT concentrations. Prepartum BB behaviour was observed in sows for a 20 min period each hour, from 18 h prior to parturition to the birth of the first piglet. Farrowing intervals were monitored between birth of the first and fifth piglet, and duration was recorded until the tenth piglet was born. Prepartum sows in CRATE showed higher frequency and tendency for increased total duration in BB behaviour than in PEN or in NEST ( P P P  > 0.10). Farrowing duration between birth of the first and tenth piglet was shorter in sows with prepartum confinement than for those not confined ( P P r  = 0.40, P