Variation in piglet mortality between and within satellites in a sow pool

Abstract: The piglet mortality rates have become a major issue in today’s pig production. While other production traits such as number of born piglets or produced piglets per sow have been improved, the mortality rate has escalated. High mortality rates before weaning does not only affect the economy but must also be looked at as both an animal welfare problem and an ethical issue. The background to this problem has been addressed many times, and its salvation has also been addressed by breeding. Breeding for increased piglet survival has been successful, but is time consuming and could not be seen as a quick fix. Through analyzes of production results, interviewing staff about management routines and herd visits has this study investigated the variation of piglet mortality within satellite herds of a sow pool, which share the same animal material but may differ in other aspects. The study focused on mortality from farrowing to weaning at approximately five weeks. It was found that there were great variation both between and within herds, even though the genetic material was the same, which indicate that the mortality rates were affected by management and housing. Furthermore, the mortality results within herds did also fluctuate heavily between batches, and could vary from 4-32%. Lower piglet mortality rates could be linked to certain management routines as many light hours during the lactation period and keeping the feed ratio of sows unchanged for the time around expected farrowing. Also, routines for identifying sow refusing to eat and the detection of the end of a farrowing was proved to be important for low mortality rates within the herd. The mortality rates were also dependent on season, party number and number of liveborn piglets in the litter.