A recent pork checkoff-funded research study investigated whether or not newly mixed sows would fight if they had previously been housed in close proximity in breeding barn stalls.

To determine the best practices for providing good sow and litter welfare in the farrowing accommodation, a good starting point is to re-examine the behavioral patterns that have been documented around farrowing and during lactation, in a natural or semi-natural environment. There is a series of behaviors carried out, with sows and piglets undergoing various phases of isolation, community integration, and living. Jensen has proposed that maternal behavior can be divided into six distinct parts: (i) isolation and nest site seeking, (ii) nest building, (iii) farrowing, (iv) nest occupation, (v) social integration, and (vi) weaning [1].

In the U.S., housing for the lactating sow and her piglets can be divided into five main areas. Total confinement (farrowing stall) houses 83.4 % of the sows. Remaining operations house far fewer sows with open buildings that have outside access at 12.4 %, open building with no outside access, 2.9 %, pasture with hut or no building, 0.7 %, and lot with hut or no building the lowest at 0.6 % [1]. Farrowing stalls have become widely accepted by the industry for numerous reasons: they have made sow management easier, efficiently utilized space, and they can help to reduce piglet mortality [2]. However, the farrowing stall has received criticism due to potential detrimental effects it may impose on the welfare of the sow (such as occurrence of shoulder ulcers [3, 4], behaviors considered problematic [5, 6, 7], and sow’s movements are more restricted). The development of an alternative, economical farrowing system that retains the advantages of the conventional farrowing stall, and provides welfare benefits to the sow and piglets, could be beneficial to the industry [8, 9].

The assessment of welfare within farrowing systems presents a unique challenge for pork producers, veterinarians, and animal scientists. Welfare assessment within all other phases of swine production involves pigs at a single stage of their productive life. Within the farrowing environment, the sow and her piglets are at two very different stages of their life, and have different requirements in regards to their thermal, social, and physical environments [1]. A system that may be ideal for the welfare needs and requirements of the sow may be far from optimal for her piglets, and vice versa. In order for objective and science-based assessments to be conducted on swine farms, we must have an appreciation of the sows and her piglets welfare during farrowing and lactation.