U.S. flagAn official website of the United States government
                    Here's how you know **Official websites use .gov**
                            
                            A **.gov** website belongs to an official government organization in the United States.
 **Secure .gov websites use HTTPS**
                            
                            A **lock** (                            
                              A locked padlock                                                      
                            
                            ) or **https://** means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.


Menu Agricultural Research Service
						
                    U.S. DEPARTMENT OF AGRICULTURE
 Food and Feed Safety Research: College Station, TX
 close



    Research

                    Research Projects
                                    Publications
                                    Collaborations
                                    News
                People

                    Staff Listing
                                    CareersSearch small
                    Search
            
            ARS Home
                                About ARS
                                Contact Us




ARS Home Plains Area College Station, Texas Southern Plains Agricultural Research Center Food and Feed Safety Research Research Publications at this Location





- ARS National Programs
- Search for a scientific manuscript
- Search for a research project
- ARS Software
- Programs and Projects
- Collaborations
- Subjects of Investigation
- Publications

Title:   Author  item
                                            Edrington, Thomasitem
                                            LONERAGAN, GUY - Texas Tech Universityitem
                                            Hill, Joshuaitem
                                            Genovese, Kenneth

                                                         - *Ken*item
                                            Harhay, Daynaitem
                                            FARROW, RUSSEL - Texas A&M Universityitem
                                            KRUEGER, NATHAN - Blinn Collegeitem
                                            Callaway, Todditem
                                            Anderson, Robinitem
                                            Nisbet, David
  Submitted to: Journal of Food Protection
                                    Publication Type: Peer Reviewed Journal
                                    Publication Acceptance Date: 3/4/2013
                                    Publication  Date: 7/10/2013
                                    Citation: Edrington, T.S., Loneragan, G.H., Hill, J.E., Genovese, K.J., Brichta-Harhay, D.M., Farrow, R.L., Krueger, N.A., Callaway, T.R., Anderson, R.C., Nisbet, D.J. 2013. Development of challenge models to evaluate the efficacy of a vaccine to reduce carriage of Salmonella in peripheral lymph nodes of cattle. Journal of Food Protection. 76:1259-1263.Interpretive Summary: Cattle may contain Salmonella, a bacteria that can make people sick.  Peripheral lymph nodes in these cattle may contain Salmonella that are not eliminated by interventions in the slaughter plant.  Vaccines are currently being evaluated for controlling Salmonella in cattle, and this research was conducted to specifically evaluate if vaccines would prevent uptake of Salmonella by the peripheral lymph nodes following oral challenge.  Results indicate that these lymph nodes can become infected with Salmonella following oral inoculation and a benefit of the vaccine as a preventative was observed.   Prior to expensive live animal field studies, our experimental model may be used to pre-screen other likely intervention strategies.
                                Technical Abstract: Recent research suggests that peripheral lymph nodes in cattle may be a significant source of Salmonella contaminating ground beef.  The objective of this research was to determine whether a commercially-available Salmonella vaccine protects calves from lymph node colonization following significant oral challenge with two strains of Salmonella frequently isolated from cattle, Salmonella Newport and Montevideo.  Three experiments were conducted in which weaned calves were randomly assigned to treatment (Control or Vaccinated) and within each treatment inoculated with either Salmonella Montevideo or Newport (8 head/treatment and each strain; 32 total).  Vaccinate calves were administered a commercially-available Salmonella Newport SRP vaccine (2 ml s.c.) while control calves received a sham-injection of corn oil (2 ml s.c.).  A second booster vaccination and sham-injections were administered on d 21.  All calves were inoculated with their respective Salmonella strain 14 d following the booster vaccination.  Calves were euthanized 14, 28, 35, and 42 days post-inoculation, and various peripheral lymph nodes were collected for Salmonella culture (quantitative and qualitative).  Fecal samples were collected throughout the experiments.  In the first experiment, the oral challenge was successful in infecting peripheral lymph nodes with both strains of Salmonella.  Few treatment differences were observed; however, at 21 d post-inoculation, Salmonella Newport-challenged calves treated with the vaccine had fewer (P < 0.05) right popliteal (0 versus 75%) and right pre-scapular nodes (0 versus 75%) that were Salmonella-positive compared to Control calves.  The percentage of Salmonella-positive left popliteal and left pre-scapular nodes likewise tended (P = 0.10) to decrease in the Vaccine treatment compared to non-vaccinated controls (Newport-challenged calves only).  Experiment II utilized a lower challenge dose (10**7) than Experiments I and III (10**10), and following two necropsies (14 and 28 d post-challenge), only one peripheral lymph node was Salmonella-positive, and the study terminated.  Experiment III utilized the higher challenge dose and examined a longer duration between challenge and necropsy.  Results were similar to the first experiment in that a higher challenge dose was successful in producing Salmonella-positive peripheral lymph nodes with each of the two challenge strains.  No significant treatment differences were observed in the Montevideo- or Newport-challenged calves, although there was a trend (P = 0.13) for fewer Salmonella-positive right sub-iliac nodes in the vaccine treatment.  When analyzed by day of necropsy, the percentage of left axillary nodes was significantly reduced (100 versus 0% for the control and vaccine treatments, respectively) by the vaccine treatment (28 d post-challenge).  Serogrouping the isolates recovered from the lymph nodes confirmed recovery of the challenge strains of Salmonella.  Herein, we are the first to document the uptake of Salmonella by the peripheral lymph nodes in cattle following significant oral challenge and provide a model for evaluating potential intervention strategies.  While few significant treatment effects were observed, the trends observed in the vaccinated calves challenged with Salmonella Newport suggests a potential benefit and warrants further research.


Return to top


Connect with ARS Sign up


ARS Home
                            USDA.gov
                            Plain Writing
                            Policies & Links
                            Civil Rights Statements
                            FOIA
                            Accessibility Statement
                            Privacy Policy
                            Non-Discrimination Statement
                            Quality of Information
                            USA.gov
                            WhiteHouse.gov