|GRAGG, SARA - TEXAS TECH UNIVERSITY|
|LONERAGAN, GUY - TEXAS TECH UNIVERSITY|
|BRASHEARS, MINDY - TEXAS TECH UNIVERSITY|
|Bosilevac, Joseph - Mick|
|Kalchayanand, Norasak - Nor|
|BROWN, TYSON - TEXAS TECH UNIVERSITY|
Submitted to: Foodborne Pathogens and Disease
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/8/2013
Publication Date: 4/8/2013
Publication URL: http://handle.nal.usda.gov/10113/56897
Citation: Gragg, S.E., Loneragan, G.H., Brashears, M.M., Arthur, T.M., Bosilevac, J.M., Kalchayanand, N., Wang, R., Schmidt, J.W., Brooks, J.C., Shackelford, S.D., Wheeler, T.L., Brown, T.R., Edrington, T.S., Brichta-Harhay, D.M. 2013. Cross-sectional study examining Salmonella enterica carriage in subiliac lymph nodes of cull and feedlot cattle at harvest. Foodborne Pathogens and Disease. 10:368-374.
Technical Abstract: Bovine peripheral lymph nodes, including subiliac lymph nodes, have been identified as a potential source of human exposure to Salmonella enterica when trim containing these nodes is incorporated into ground beef. In order to gain a better understanding of the burden of S. enterica in subiliac lymph nodes of feedlot and cull cattle at harvest, 3,327 subiliac lymph nodes were collected from cattle in 3 geographically distinct regions of the U.S. Overall crude prevalence of S. enterica was 8.0% (95% confidence limits [CL]=7.1, 8.9%). Prevalence was greater in feedlot cattle (15.5% [95% CL=13.7, 17.4%]) compared to cull cattle (1.8% [95% CL= 1.2, 2.4%]). Of the 618 feedlot cattle lymph nodes subjected to enumeration, 144 nodes harbored S. enterica, and estimates of concentration were <1.3 Log10 CFU/lymph node in 21.5% of nodes, 1.3 to 2.9 Log10 CFU/lymph node in 44.4%, 3.0 to 4.5 Log10 CFU/lymph node in 20.8%, and >4.5 log10 CFU/lymph node in 13.2%. The majority of serotypes recovered from lymph nodes were S. Montevideo (44.0%) and S. Anatum (24.8%). The majority (86.6%) of isolates were pansusceptible to a panel of 15 antimicrobial agents; however, multi-drug resistant isolates (7.1%) were also occasionally observed. Data indicate that Salmonella is readily recovered from the subiliac lymph nodes of cattle, and additional research is necessary to mitigate potential risk to food safety.