The prevalence of Campylobacter spp. and Yersinia enterocolitica was determined in cohorts of growing pigs on eight swine farms in Iowa and North Carolina. Approximately 60 pigs from each site were periodically sampled from the nursery to slaughter. Both all in/all out and continuous flow production systems were monitored. Overall, when results from the two states are combined, Campylobacter coli was found in the nursery (90%), grower (92.8%) and finisher (90.9%) stages. At slaughter, C. coli was detected overall on 17.1% of carcasses. For Iowa, 83% of ileocaecal lymph nodes yielded Campylobacter. In contrast, Y. enterocolitica was not found in either rectal or tonsilar swabs or in carcass swabs collected from Iowa hogs. Y. enterocolitica was detected in 8.8% (5 of 57) of North Carolina hogs sampled on one occasion; no isolations were made from carcass swabs at slaughter.