Management of High Prolificacy in French Herds: Can We Alleviate Side Effects on Piglet Survival?

In general the development of hyper prolific sows has been associated with a dramatic increase in perinatal mortality. Analysis of the performance of French sow herds (IFIP, 2007) indicates that total number of piglets born per litter increased from 11.9 in 1996 to 13.8 in 2006. Simultaneously, total mortality increased from less than 19% up to 21%, with about 25% of herds losing more than 25% of piglets born before weaning (Badouard, personal communication). Stillborn piglets (8% of total born) presently account for about 40% of total mortality. With 12.7 born alive per litter, mortality frequently reaches 15% during lactation, mainly due to crushing of starved and weak piglets. However, the size of weaned litters and sow productivity are still increasing with prolificacy (Figure 1), without an apparent negative impact on sow fertility or longevity (Boulot, 2004). In 2006, the 10% most efficient French farms (n=280) weaned 30 piglets/productive sow /year, with 14.3 total born per litter and only 17.3% total piglet losses. That may represent a somewhat optimistic perception of prolificacy, despite negative ethical impacts and economic wastes.