Mixing Of Pregnant Sows Is Stressful & Affects Development Of Piglets
Published: Mon, 10 Jan 2005
Research Note Full Title
Mixing of pregnant sows is stressful and affects development of piglets
Since the ban of the tethered stall system for pregnant sows in the UK in 1999, pregnant sows must be group-housed. While this is seen as an improvement in sow welfare, there are still some concerns over the social stress that can occur following repeated mixing of pregnant sows. In addition, research in rodents and humans has indicated that stress during pregnancy may have long-term negative effects on the development of offspring.
Objectives
Research at SAC has addressed the issue of whether social stress associated with mixing during pregnancy has negative impacts on the development of piglets. Gilts were mixed during either their 2nd or 3rd trimester of pregnancy and their piglets’ production, behavioural and brain development were examined.
Outcomes
Achievements
Production: Piglets from gilts mixed during pregnancy showed reduced weight gain post-weaning but had caught up by 7 weeks of age.
Brain development: Alterations in brain development indicative of higher stress reactivity and anxiety were found in piglets whose mothers had been mixed during pregnancy.
Behaviour: Piglets from gilts mixed in the 2nd trimester of pregnancy showed more persistent aggression post-weaning, and 12 months later when these piglets became gilts and farrowed themselves, they showed increased aggression towards their piglets.
Implications
Mixing during pregnancy is not only stressful for the gilts and sows themselves, but also has long-term detrimental consequences on piglet development. These effects were most apparent when mixing occurred in the 2nd trimester. Therefore mixing should be avoided if possible and particularly during the middle trimester of pregnancy.
Sponsors & Partners
Research Sponsors
SEERAD (May 2007 onwards, Scottish Executive Rural Directorate (SERD))
Research Partners
SAC, University of Edinburgh