Addressing pain at parturition in the pig

This research project addressed pain at parturition in pigs using three different approaches. Firstly, a survey study explored UK pig farmer and veterinarian attitudes to pain and the use of pain relief in order to understand the commercial context behind decisions relating to pain and its management. Secondly, an observational study was conducted to investigate the use of behaviour to assess pain associated with the process of giving birth (or farrowing) in pigs. A final experimental study was used to investigate the administration of a pain relief drug post-farrowing to improve pig welfare and increase productivity. In a questionnaire to farmers and veterinarians, individuals were asked to identify the anti-inflammatory drugs they used or prescribed and how often for selected conditions in pigs. They were also asked to rate the painfulness of different conditions and indicate their level of agreement with statements about pain and the use of pain relief. Results showed anti-inflammatories were widely used, with high agreement that pigs recovered better when given these drugs. Farmers and vets gave similar scores for painful conditions but females and younger respondents scored higher for specific conditions. The results suggest that potential barriers to the increased use of pain relief include a lack of up to date knowledge and communication between farmers and vets about pain and how best to treat it. A preliminary investigation was conducted to identify novel behavioural measures to assess pain in sows over the periparturient period. A set of spontaneous putative pain behaviours were characterised and quantified, using observations of sows before, during and after farrowing. These potential behavioural pain indicators were rare or absent before farrowing and the highest levels were seen during farrowing. For the post-farrowing observations, levels were highest for the immediate post-farrowing period and remained higher than pre-farrowing values up to 24 hours after the last piglet was born. Positive correlations between behavioural variables measured during and after farrowing indicate the individual consistency in the expression of these behaviours. Putative pain behaviours, along with other measures of welfare and productivity were then used to test the benefits of administering the non-steroidal anti-inflammatory drug ketoprofen, compared with a saline placebo, 1.5 hours post farrowing in primiparous and multiparous sows. No clear treatment differences were observed for the sow welfare measures, including the putative behavioural indicators of pain. For primiparous sows treated with ketoprofen, fewer piglets died, but this could be due to an unexpected treatment difference in piglet birth weight, which is strongly linked with piglet mortality. Further research is needed to validate the spontaneous behaviours used in this study as indicators of pain in periparturient sows.