Increasing available space in a farrowing crate does not facilitate postural changes or maternal responses in gilts

A study was designed to test the effects of gestation and farrowing accommodation on the postural behaviour and maternal responsiveness of gilts. It was hypothesized that increasing available space would allow gilts to move more easily, facilitating maternal responses. Twenty-four gilts were allocated to either an individual stall or small group for gestation, followed by either a narrow crate (42.5 cm wide), wide crate (80 cm wide) or pen (2.4 m X 2.4 m) for farrowing and lactation. Postural time budget and standing and lying behaviour were observed on seven occasions during farrowing accommodation occupancy. Maternal responsiveness was tested on d 2 after farrowing by observing each gilt's response to a tape recorded piglet distress squeal, played while she was in the process of lying down. Five days before farrowing (d-5) and one day before farrowing (d-1), postural behaviour indicated restlessness: 65% of time was spent lying laterally, compared to over 80% immediately after farrowing (d 1), and gilts spent about twice as much time standing and sitting on d-5 and d-1 as they did on d 1. Gilts changed posture more than four times as often in the prepartum period than postpartum. This prepartum restlessness was more marked in the wide crate than in the narrow crate or pen, particularly when gilts had gestated in groups. On d-1, gilts in the wide crate spent less time lying in lateral recumbency (55% of time vs. 76%, p < 0.01) and more time lying in sternal recumbency (20% of time vs. 10.5%, p < 0.05) than gilts in the narrow crate or pen. Occupants of the wide crate displayed more bouts of both kinds of lying (p < 0.01) than other gilts, and shorter bouts of lateral lying(p < 0.05) than gilts in the pen on d-1. In the wide crate, gilts that had gestated in groups lay sternally for 30% of time prior to farrowing, compared to 10% of time in previously stalled animals (p < 0.01), and displayed more bouts of sternal lying (p < 0.01). Gilts in the wide crate lay down more slowly (18.2 s) than those in either the narrow crate (13.1 s) or pen (12.0 s), (p < 0.05). Wide crate occupants also used the crate side for support during lying down less than half as often as gilts in the other two kinds of farrowing accommodation ton 35% vs. 72-89% of occasions, p < 0.01), but use or non-use of a support did not affect time taken to lie down in the wide crate. Maternal response to the squeal playback was very variable, and was not affected by gestation or farrowing accommodation. The widened farrowing crate appeared less comfortable than either the narrow crate or pen, particularly when it followed gestation in a group. Contrary to expectations, increasing the available space in a crate did not facilitate posture-changing behaviour. The importance of controlling for type of gestation accommodation when examining the effects of farrowing housing on behaviour is emphasized. (C) 1998 Elsevier Science B.V. All rights reserved.