Watai, Y., Uchihashi, M. 2021. Group housing procedure of laboratory farm pigs. Laboratory Animal Science Professional 9(5) (September/October), 58-60.

Our initial attempt was to individually place pigs in cages according to the serial numbers assigned by the vendor and remove cage inserts to combine those that happened to be next to each other. Unfortunately, this resulted in many fighting incidents. To investigate the cause of fighting, we re-evaluated information on the shipping slip from the vendor. The slip listed farm, serial number, individual identification (ID) number, sex, date of birth (DOB), and body weight (BW). This vendor owned 2 farms, and we had an impression that grouping pigs from Farm 2 resulted in fewer fights than Farm 1. We discussed with the vendor, and they agreed to provide more detailed information for each farm and add the final housing location (FHL) of each pig on the shipping slip. We learned that pigs were always group housed at Farm 2, while at Farm 1, pigs may be singly housed in pre-shipment to control BW. Additionally, each shipment could include pigs from different facilities, rooms, or pens/cages. Based on this additional information, we conducted 2 trials seeking to reduce the incidence of fighting and percentage of singly housed pigs. In this article, we share our findings and conclusions.