Systemic inflammatory response to shoulder ulcers and lack of preventive effect of postpartum pain medication with ketoprofen in sows

•Bilateral shoulder ulcers trigger a systemic inflammatory response.•Ketoprofen admistered for two days after farrowing does not prevent the development of shoulder ulcers in sows.•Ketoprofen increases the prevalence of shoulder ulcers at the second and third lactation week.•Body condition score is an important protective factor against shoulder ulcers.