42 Group sow housing considerations for improved survival and productivity

Abstract Group sow housing considerations for improved survival and productivity. The Australian pork industry decided in 2010 to voluntarily phase out stall housing for pregnant sows by 2017. The change was supported by extensive R&D by the Pork CRC for High Integrity Australian Pork and the time line was brought forward by two major retailers in Australia. For 85 to 90% of producers the transition was complete by 2019-2020 and sows were grouped at weaning or straight after mating. I reviewed the pertinent literature, interviewed many producers on what is required to make group housing successful for the sow and the producer and looked at trend from an Australian bench making project in some aspects of reproduction and sow mortality from 2006 to 2020. The research showed sows adapt to grouping and exhibit reduced aggressive behaviors, injuries and plasma indicators of stress within 4 to 5 d after mixing. During this period, it was all about space at mixing, grouping sows based on size/parity, ensuring they all receive adequate feed and familiarization with group housing by the sow and staff. Producers said it is all about ensuring sows are grouped on size/parity, feeding with many using ad libitum feeding for the week after mixing, space with a preference between 1.8 and 2.2 m2, flooring (slats preferred) and minimizing mixing events. Producers were split on the use of drop feeding and electronic sow feeders with opinions very divided. For drop feeding the preferred housing system comprised full length feeding stalls without a back gate. All producers said they would not go back to stalls. Most producers experienced a decline in farrowing rate and increased lameness during the transition. However, reproduction improved over time and sow mortality decreased. If the top 4 to 5 factors affecting aggressiveness and overall welfare are followed, group housing sows improves their welfare and does not reduce their reproductive performance or longevity. Detection of estrus can be more difficult in groups and a number of Australian producers have implemented the use of satiety blocks during the first 2 and last 2 wk of gestation to further improve welfare and meet retailer requirements. Mating in groups (not stalls) has also been reported to improve reproduction.