Group housing for lactating sows with electronically controlled crates has been investigated by A-L. Bohnenkamp of Christian-Albrechts University in Kiel and co-authors there and the Chamber of Agriculture fo Schleswig-Holstein.

Their recent paper in Journal of Animal Science reports an experiment, the aim of which was to compare a group housing system (G) and a conventional individual housing (S) for lactating sows with regard to the performance of sows and piglets.

Data of 132 cross-breed sows were collected in 11 batches with six sows in G and S in each batch. The G group had single pens (4.7 square metres) with electronically controlled crates and a shared open area (13 square metres). The sows in G were retained in the crates for three days before farrowing until one day post-partum. Piglets were able to leave the single pens on day 5 post-partum.

Recorded traits per litter included the number of piglets born alive and weaned, piglet losses and individual weight at birth and weaning. In addition, body condition and back fat thickness before and after lactation (26 days) and the daily feed intake of the sows were measured. Gilts and sows were analysed separately.

The reproductive traits did not differ significantly (P>0.05) between the farrowing systems with exception of the weaning weights (G = 7.6 ± 0.12kg versus S = 8.1 ± 0.12kg; P<0.05).

G and S sows had 14.4 ± 0.47 and 14.6 ± 0.45 piglets born alive, respectively.

In both housing systems, sows weaned 11.4 piglets (SEM = 0.14 and 0.13 for G and S), respectively.

Most piglet losses - 72 per cent - occurred during the first three days post-partum. At this point in time, piglets in G and S were housed in single pens. In the single pens, G sows could leave the farrowing crate whereas S sows were in crates during the whole lactation.

In total, piglet losses were not significantly different during lactation between G and S treatments (2.2 ± 0.05 and 2.4 ± 0.05 piglets per litter, respectively).

Sows housed in G had a significantly lower (P<0.05) body condition score (2.2 ± 0.05) after lactation compared with S sows (score = 2.4 ± 0.05). This development could not be verified using the back fat thickness value at weaning (G = 14.4 ± 0.25mm versus S = 14.6 ± 0.23mm).

Daily feed intake was significantly greater for G sows (6.4 ± 0.08kg per day) than S sows (6.15 ± 0.08kg per day; P<0.05).

The performance of G and S sows was generally similar, concluded Bohnenkamp and co-authors, although they remarked that weaning weights were lighter for the G housing.

Reference

^{Bohnenkamp A-l., I. Traulsen, C. Meyer, K. Müller and J. Krieter. 2013. Group housing for lactating sows with electronically controlled crates: 1. Reproductive traits, body condition, and feed intake. J. Anim. Sci. 91(7):3413-3419. doi: 10.2527/jas.2012-5255}

September 2013