|Morrow, J. - LIRV LUBBOCK|
|Dailey, J. - LIRV LUBBOCK|
Submitted to: American Society of Animal Science
Publication Type: Abstract Only
Publication Acceptance Date: July 22, 2002
Publication Date: N/A
Technical Abstract: Weaned pigs are often transported to grower facilities and co-mingled without regard to farm of origin. This study examines the effect of mixing stress on Salmonella status in segregated early-weaned pigs. Piglets (7 d old n=28) were divided into 4 groups (2 controls and 2 mixed groups). One pig in each group of 7 was challenged with 10**9 CFU S. typhimurium (ST) via oral gavage. ST status was evaluated daily by rectal swab. In the mixed groups, 1 pig each day for 5 days was moved from one mixed group to the other mixed group to stimulate mixing stress. The control groups were not mixed. Behavior was constantly monitored in all 4 groups. The mixed pig groups were significantly more stressed compared to controls, as demonstrated by increased aggressive behavior, decreased rooting and eating, more ST positive and increased ST numbers in rectal samples. After necropsy, pigs in mixed groups had increased numbers of ST positive tonsils and lymph nodes however no differences in cecal ST positive pigs were observed compared to controls. Results suggest that mixing groups of pigs from different farms can cause social stress that may increase susceptibility to ST.