Updated Scientific Evidence on the Welfare of Gestating Sows Kept in Different Housing Systems
A review of recent papers revealed similar productivity, physiology, health and behaviour among individually or grouped sows during pregnancy.Gestation sow housing is a contemporary animal welfare issue with legislative actions in the United States to ban individual gestation sow systems. In a review published in Professional Animal Scientist, John McGlone of Texas Tech University explains that his review seeks to summarise the scientific literature since earlier reviews were published in 2004 and 2005.
Seventeen papers comparing effect of housing systems on the welfare of gestating sows were published between 2005 and 2012.
Stalls or crates, tether housing and group pens including conventional group pens, loose-house pens, electronic sow feeders pens and hoop barns were reported.
The majority of recent findings were similar to the previous conclusions from papers and reviews, Dr McGlone reports. Cortisol concentrations were not different between stalled and group-penned sows but were higher shortly after mixing in concert with increased sow aggression and skin lesions. The effects of gestation housing system on neutrophil:lymphocyte ratio were still mixed.
In the recent literature, stereotypical behaviour was greater among stalled sows than group-penned sows, which may reflect a change in sow genetics because the basic housing systems have not changed.
Recent papers indicated more sitting or standing inactive, leg and claw problems and higher farrowing rate (in some studies) among stalled sows. Other studies reported more lying down among group-penned sows and no differences in other reproductive and productivity measures between stalled and group-penned sows.
Weaning-to-oestrus intervals were similar for stalled and group-penned sows in contrast to previous reviews that observed a shorter interval among stalled than grouped sows.
Dr McGlone concludes that recent papers found similar productivity, physiology, health, and behaviour among individually or grouped sows during gestation.
Reference
McGlone J.J. 2013. Review: Updated scientific evidence on the welfare of gestating sows kept in different housing systems. Professional Animal Scientist 29(3):189-198.
June 2013