Figure 1
From: A 25 years experience of group-housed sows–reproduction in animal welfare-friendly systems
Phenotypic trends in Swedish piglet production, based on data from the herd monitoring program PigWin (Svenska Pig, 2013 [[47]]). a) Weaning to service interval (WSI) and number of non productive days (NPD). b) Litter size, number of liveborn piglets (Liveborn) and number of weaned piglets (Weaned) per litter. c) Piglet mortality, number of stillborn piglets (No. stillborn) and number of piglets died during suckling period (Mort. suckling period) per litter.