Progress 10/01/07 to 09/30/12
Outputs
OUTPUTS: We used interdisciplinary research teams to generate important research results relevant to prevention and control of enteric bacteria and viruses; primarily, but not exclusively focused on Escherichia coli O157:H7, other Shiga toxin-producing E. coli (STEC), Salmonella, Noroviruses, and antimicrobial resistance of enteric bacteria in cattle and swine. Activities include developing and enhancing methods for characterizing and detecting enteric pathogens, including STEC serogroups O26, O45, O103, O111, O121, O145, O104 and O157 and major virulence genes for STEC and enteroaggregative E. coli pathotypes. In addition, we have evaluated, developed and improved prevention and intervention strategies to reduce enteric pathogen burden. We performed studies of enteric pathogens to evaluate vaccines, direct-fed microbials, livestock diets, epithelial cell signal transduction pathways, regulation of nuclear translocation, host transcriptional responses to bacterial infection, subversion of innate immune responses, and broad-spectrum antivirals. We also provided training on control of enteric pathogens to students, producers, veterinarians, and other scientists. We have mentored multiple veterinary students and graduate students in veterinary pathobiology, public health, food science programs. We have delivered manuscripts as well as oral and poster presentations of the results of these studies to the scientific community and industry representatives at several regional, national, and international scientific meetings. In addition, press releases have been used to disseminate the important research outcomes to a broader audience. PARTICIPANTS: Principal Investigators: David G. Renter (Station Rep), Kyeong-Ok Chang, T.G. Nagaraja, Jerome Nietfeld, Ludek Zurek. Collaborators: Phil Hardwidge, Mike Sanderson, H. Morgan Scott, Dan Thomson, Jim Drouillard, Xiaorong Shi, Jianfa Bi, Megan Jacob, Yunjeong Kim, Natalia Cernicchiaro. Students and post-doctoral fellows: Ashley Smith, Charley Cull, Zach Paddock, R. Amachawadi, G. Agga, L. Schaefer. TARGET AUDIENCES: Veterinarians, researchers, scientific extension personnel, cattle producers, industry organizations, animal scientists, and the general public. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
Our results under Objective 1 provided useful information on enteric pathogens in food and food animal production environments. We have generated prevalence estimates for STEC in feces of commercial feeder cattle, which are critical to populate risk assessments and identify potential risks of human illness due to STEC infections. We also determined that STEC from the feces of US feedlot cattle do not appear to carry genes characteristic of the virulent hybrid strain of STEC O104 that caused the large foodborne outbreak in Germany and France in 2011. In addition, we found that steam-flaked corn in cattle feedlots is a hotspot for deposition and acquisition of E. coli and other coliforms by house flies; methods to reduce fly access to SFC should be evaluated in order to reduce bacterial contamination. Our results under Objective 2 provided useful information on interventions for reducing enteric bacteria and viruses. We quantified the effects of preharvest interventions targeting STEC O157 on fecal shedding non-O157 STEC serogroups. We confirmed that feeding cattle distillers grains (DG) increases fecal shedding of E. coli O157:H7; unfortunately the addition of starch to a DG-supplemented diet did not negate the effects of DG on fecal shedding of E. coli O157:H7. Our findings on the intestinal epithelial cell signal transduction pathways activated by ETEC and the relative importance of these host pathways to enterotoxin(LT)-induced ETEC adherence provide insight into previously unexplored functions of LT and their relative importance to ETEC virulence. We found that IKKbeta-dependent modification of a specific amino acid in RPS3 promoted specific NF-kappaB functions that underlie the molecular pathogenetic mechanisms of E. coli O157:H7. In addition, we demonstrated that the two copies of E. coli O157:H7 non-locus of enterocyte effacement-encoded protein H, designated NleH1 and NleH2, have pronounced functional differences in their ability to alter host transcriptional responses to bacterial infection. Our results show that enterotoxigenic E. coli evade the host innate immune response by directly modulating NF-kappaB signaling. We also have identified compounds that have potential as antiviral therapeutics aimed at a single virus or multiple viruses in the picornavirus-like supercluster, which includes picornaviruses, caliciviruses and, coronaviruses, by targeting 3Cpro or 3CLpro. In addition, our results suggest a crucial role of lipid metabolism in rotavirus replication, and triacsin C and/or its analogs as potential therapeutic options for rotavirus infections. We provided educational opportunities to professional and graduate students, as well as continuing education to veterinarians, to enhance their understanding of STEC and Salmonella in the beef industry, the conclusions that can be reached based on research, and the opportunities to reduce these pathogens in beef production systems. In addition, we produced and disseminated a review of the latest findings about Ribosomal Protein S3 extraribosomal functions, with special emphasis on their relation to microbial pathogenesis and enteropathogenic E. coli.
Publications
- Wang X, Gao X, Hardwidge PR. Heat-labile enterotoxin-induced activation of NF-kappaB and MAPK pathways in intestinal epithelial cells impacts enterotoxigenic Escherichia coli (ETEC) adherence, Cellular Microbiology, 2012 Aug;14(8):1231-41. PMID: 22452361.
- Kim Y, Lovell S, Tiew K, Mandadapu SR, Alliston KR, Battaile KP, Groutas WC, Chang K. Novel Broad-Spectrum Antivirals against 3C or 3C-like proteases of Picornaviruses, Noroviruses and Coronaviruses. Journal of Virology, 2012, 86(21):11754-62.
- Cull CA, Paddock ZD, Nagaraja TG, Bello NB, Babcock AH, Renter DG. Efficacy of a vaccine and a direct-fed microbial against fecal shedding of Escherichia coli O157:H7 in a randomized pen-level field trial of commercial feedlot cattle. Vaccine 2012; 30(43): 6210-6205.
- Pham T, Gao X, Tsai K, Olsen R, Wan F, Hardwidge PR. Functional differences and interactions between the E. coli type III secretion system effectors NleH1 and NleH2, Infection & Immunity, 2012 Jun;80(6):2133-40. PMID: 22451523.
- Wan F, Weaver A, Gao X, Bern M, Hardwidge PR, Lenardo MJ. IKKβ phosphorylates RPS3 to regulate its nuclear translocation and NF-kB specifier function, Nature Immunology 2011 Apr;12(4):335-43. PMID: 21399639.
- Gao, X, Hardwidge PR. Ribosomal protein S3: A multifunctional target of bacterial pathogens, Frontiers in Cellular and Infection Microbiology, 2011, 2:137. PMCID: PMC3125523.
- Kim Y, George D, Prior AM, Prasain K, Hao S, Le DD, Hua DH, Chang K. Novel triacsin C analogs as potential antivirals against rotavirus infections. Eur J Med Chem, 2012, 50:311-8.
- Jacob ME, Nagaraja TG. Use of direct-fed microbials as a preharvest food safety intervention in cattle. p 189-202. In: Direct-Fed Microbials and Probiotics for Animals: Science and Mechanisms of Action. T. R. Callaway and S. C. Ricke (eds.) 2012. Springer Publ., NY.
- Bai J, Paddock ZD, Shi X, Li S, An B, Nagaraja TG.. Applicability of a Multiplex PCR to detect the seven major Shiga toxin-producing Escherichia coli based on genes that code for serogroup-specific O-antigens and major virulence factors in cattle feces. Foodborne Path Dis. 2012, 9:541-548.
- Paddock ZD, Shi X, Bai J, Nagaraja TG. Applicability of a multiplex PCR to detect O26, O45, O103, O111, O121, O145, and O157 serogroups of Escherichia coli in cattle feces. Vet Microbiol 2012, 156:381-388.
- Jacob ME, Shi X, An B, Nagaraja TG, Bai J. Evaluation of a multiplex real-time PCR for the quantification of Escherichia coli O157 in cattle feces. Foodborne Path Dis 2012, 9:79-85.
- Agga GE, Scott HM, Vinasco-Torres, Amachawadi RG, Nagaraja TG, Tokach M, Nelssen J, Dritz S, Renter DG, Bai J, Norby B. Effects of chlortetracycline and copper supplementation on tetracycline and ceftiofur resistance determinants in piglet feces. 6th International conference on Antimicrobial Agents in Veterinary Medicine (AAVM), Washington, DC, 2012.
- Renter DG. Food Safety in the Beef Industry: Successes and Challenges. Academy of Veterinary Consultants, Washington, DC. 2012.
- Sanderson MW, Jacob ME, Dodd CC, Renter DG. Impact of intervention failures and vaccination on beef carcass E. coli O157 contamination. International Symposium of Veterinary Epidemiology and Economics (ISVEE) 2012. Maastricht, the Netherlands. Proceedings p 365.
- Renter DG, Cull C, Paddock ZD, Bello NM, Nagaraja TG. Efficacy of the SRP vaccine and/or low-dose Bovamine against fecal shedding of E. coli O157:H7 in a randomized field trial of commercial feedlot cattle. Annual Meeting of the Institute of Food Technologists, Las Vegas, NV. 2012.
- Renter DG. Efficacy of the SRP vaccine and/or low-dose Bovamine against fecal shedding of E. coli O157:H7 in a randomized field trial of commercial feedlot cattle. Beef Industry Safety Summit, Tampa, FL. 2012.
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Progress 01/01/11 to 12/31/11
Outputs
OUTPUTS: We have used interdisciplinary research teams to generate important research results relevant to prevention and control of enteric bacteria and viruses; primarily, but not exclusively focused on E. coli O157:H7, other Shiga toxin-producing E. coli (STEC), Salmonella, Noroviruses, and antimicrobial resistance of enteric bacteria in cattle and swine. Activities include: 1) development of a multiplex PCR to detect the seven major STEC based on genes that code for serogroup-specific O-antigens and major virulence factors in cattle feces; 2) an evaluation of Escherichia coli O157:H7 genetic diversity in bovine fecal samples; 3) a study of tcrB gene mediated copper resistant fecal enterococci in pigs fed diets supplemented with copper; 4) characterization of antibiotic resistant and virulent enterococci from animal feed; 5) a study of antibiotic resistant and potentially virulent enterococcal from insects in confined swine operations; 6) a study of characterization and inhibition of norovirus proteases of genogroups I and II using a fluorescence resonance energy transfer assay; and 7) an estimation prevalence of STEC serogroup O26 in feces of feedlot cattle. In addition, we have studied: 1) the effects of a vaccine and a direct-fed microbial on fecal shedding of E. coli O157:H7 and O26 in pens of commercial feedlot cattle fed a diet supplemented with distiller's grains; 2) the inhibitory effects of bile acids and synthetic Farnesoid X receptor agonists on rotavirus replication; and 3) the effects of bacterial transfer rates and interventions on the prevalence and concentration of E. coli O157 on beef carcasses. We have mentored multiple veterinary students and graduate students in veterinary pathobiology, public health, food science programs. We have delivered manuscripts as well as oral and poster presentations of the results of these studies to the scientific community and industry representatives at several regional, national, and international scientific meetings. In addition, press releases have been used to disseminate the important research outcomes to a broader audience. PARTICIPANTS: Principal Investigators: David G. Renter (Station Rep), Kyeong-Ok Chang, T.G. Nagaraja, Jerome Nietfeld, Ludek Zurek Collaborators: Mike Sanderson, H. Morgan Scott, Dan Thomson, Jim Drouillard, Xiaorong Shi, Jianfa Bi, Megan Jacob, Brad White, Bob Larson, Jan Sargeant, Mohammed Alam, Yunjeong Kim Students and post-doctoral fellows: Chuck Dodd, Megan Jacob, Ethel Taylor, Zach Paddock, Greg Peterson, R. Amachawadi, Jason Nickell, Laura Schaefer, TARGET AUDIENCES: Veterinarians, researchers, scientific extension personnel, cattle producers, industry organizations, animal scientists, and the general public PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
Our results under Objective 1 have provided useful information on the detection, transmission, dissemination, persistence and survival of enteric bacterial and viral pathogens in food and food animal production environments. We have developed assays to detect major serogroups and virulence genes of STEC and have demonstrated the diversity of STEC O157 strains in bovine fecal samples. We have demonstrated that supplementation of copper in swine diets may be associated with antimicrobial resistance in fecal enterococci. In a separate study, we demonstrated that antimicrobial resistant and potentially virulent enterococci may be present in swine feed at feed mills and farms. In addition, we have shown that insects in swine production environments may serve as vectors or reservoirs of antimicrobial resistant and potentially virulent enterococci. For Noroviruses, we have established a high throughput assay that may be useful for screening potential antivirals or studying enzyme-substrate interactions. We also have described the prevalence, distribution, and frequency of virulence genes of STEC O26 in feedlot cattle. Our results under Objective 2 have provided useful information on potential and applied interventions for reducing foodborne enteric bacteria and viruses. We have quantified the effects of commercial available preharvest interventions targeting STEC O157 on fecal shedding of STEC O157 and O26. We have shown that bile acids and FXR agonists play important roles in the suppression of rotavirus replication, which may serve therapeutic option for rotavirus infection in animals and humans. In addition, we have quantified the effects of post-harvest interventions as well as the influence of bacterial transfer between cattle feces, hides and carcasses on the prevalence and concentration of O157 on beef cattle carcasses.
Publications
- Dodd C, Sanderson MW, Jacob M, Renter DG. Modeling preharvest and harvest interventions for Escherichia coli O157 contamination on beef cattle carcasses. J Food Prot. 2011; 74(9):1422-1433. Nickell JS, White BJ, Larson RL, Renter DG, Sanderson MS, Peck C. Bovine Viral Diarrhea Virus (BVDV) Status in cow-calf herds and associations with biosecurity and production practices among Montana beef producers. Bov Pract. 2011; 45(1): 14-22. Dodd C, Renter DG, Shi X, Alam MJ, Nagaraja TG, Sanderson MW. Prevalence and persistence of Salmonella in cohorts of feedlot cattle. Foodborne Pathog Dis. 2011; 8(7): 781-789. Nickell JS, White BJ, Larson RL, Renter DG, Sanderson MW. A simulation model to quantify the value of implementing whole-herd Bovine Viral Diarrhea Virus testing strategies in beef cow/calf herds. J Vet Diagn Invest. 2011; 23(2): 194-205. Dodd CC, Renter DG, et al. Evaluation of the effects of a commercially available Salmonella Newport siderophore receptor and porin protein vaccine on fecal shedding of Salmonella bacteria and health and performance of feedlot cattle. Am J Vet Res., 2011; 72(2): 239-247. Taylor E, Renter DG, Nagaraja TG. Genetic variations in shiga toxin-producing abilities of bovine and human Escherichia coli O157:H7. Zoonoses Public Health, 2011; 58(3): 185-91. Sargeant JM, O'Connor A, Renter DG, Kelton D, Snedeker K, Wisener L, Leonard E, Guthrie A, Faires M. Reporting of methodological features in observational studies of pre-harvest food safety. Prev Vet Med., 2011; 98(2-3): 88-98. Paddock, Z. D., C. E. Walker, J. S. Drouillard, Nagaraja T.G.. Dietary monensin level, supplemental urea, and ractopamine on fecal shedding of Escherichia coli O157:H7 in feedlot cattle. J. Anim. Sci., 2011; 89:2829-2835. Amachawadi, R. G., N. W. Shelton, X. Shi, J. Vinasco, S. S. Dritz, M. D. Tokach, J. L. Nelssen, H. M. Scott, T. G. Nagaraja. Selection of tcrB gene mediated copper resistant fecal enterococci in pigs fed diets supplemented with copper. Appl. Environ. Microbiol., 2011; 77:5597-5603. Jacob, M. E., K. M. Almes, X. Shi, J. M. Sargeant, and T. G. Nagaraja. Escherichia coli O157 diversity in bovine fecal samples. J. Food Prot., 2011; 74:1186-1188. Yunjeong Kim and Kyeong-Ok Chang. Inhibition of Rotavirus replication by Bile Acids through Farnesoid X Recepter. J Virol., 2011; 85(23):12570-7. Aqeel Ahmad, Anuradha Ghosh, Coby Schal, and Ludek Zurek. Insects in confined swine operations carry a large antibiotic resistant and potentially virulent enterococcal community. BMC Microbiol., 2011; 11(1):23. Daisuke Takahashi, Yunjeong Kim, Kyeong-Ok Chang, Asokan Anbanandam, Om Prakash. 2011. 1H, 15N, and 13C resonance assignments of Norwalk virus protease. Biomol NMR Assign. Jun 8. [Epub ahead of print] Jacob, M. E., X. Shi, B. An, T. G. Nagaraja, and J. Bai. Evaluation of a multiplex real-time PCR for the quantification of Escherichia coli O157 in cattle feces. Foodborne Path. Dis. In Press. Paddock, Z., X. Shi, J. Bai, and T.G. Nagaraja. Applicability of a multiplex PCR to detect O26, O45, O103, O111, O121, O145, and O157 serogroups of Escherichia coli in cattle feces. Vet. Microbiol. In Press. Kyeong-Ok Chang, Daisuke Takahashi, Om Prakash, and Yunjeong Kim. Characterization of Proteases from Norovirus Genogroup I and II with the Fluorescence Resonance Energy Transfer Assay. Virology. In Press.
- Published Abstracts: Cull C, Renter DG, Paddock ZD, Bello NM, Babcock AH, Nagaraja TG. Effects of a vaccine and a direct-fed microbial on fecal shedding of E. coli O157:H7 in pens of commercial feedlot cattle fed a diet supplemented with distiller's grains. Conference of Research Workers in Animal Disease, Chicago, IL, 2011. #86. Paddock ZD, Renter DG, Cull C, Schaefer LA, Shi X, Li S, Bai J, Nagaraja TG. Fecal shedding of Escherichia coli O26 in feedlot cattle from a field trial evaluating an Escherichia coli O157:H7 vaccine and a direct-fed microbial. Conference of Research Workers in Animal Disease, Chicago, IL, 2011. #87. Jacob M, Sanderson M, Dodd C, Renter DG. Modeling the effect of bacterial transfer rates and interventions on the prevalence and concentration of Escherichia coli O157 on beef carcasses. Conference of Research Workers in Animal Disease, Chicago, IL, 2011. #89. Schaefer LA, Paddock ZD, Cull C, , Shi X, Li S, Bai J, Nagaraja TG, Renter DG. Prevalence of Shiga toxin-producing Escherichia coli serogroup O26 in feces of feedlot cattle. Conference of Research Workers in Animal Disease, Chicago, IL, 2011. #38P. Amachawadi, R. G., H. M. Scott, N. W. Shelton, M. D. Tokach, J. Vinasco, T. R. Mainini, S. S. Dritz, J. L. Nelson, and T. G. Nagaraja. 2011. Effects of feeding copper sulfate, tetracycline, and tylosin on the prevalence of of transferable copper resistance gene, tcrB, among fecal enterococci in swine. Conference of Research Workers in Animal Disease, Chicago, IL, 2011. #92. Renter DG. Food Safety and the Beef Industry - Key Messages to Share and Pre-harvest Issues to Consider. Academy of Veterinary Consultants, Denver, CO. 2011. Renter DG, Jacob M, Paddock Z, Cull C, Nagaraja TG. Escherichia coli O157:H7 effects related to feeding cattle distiller's grains. Joint meeting of the American Society for Animal Sciences and Asociacion Argentina de Produccion Animal, Argentina, 2011. Paddock, Z. D., X. Xiaorong, T. G. Nagaraja, and J. Bai. 2011. Detection of major serotypes of Shiga-toxin producing E. coli in bovine feces by multiplex PCR. J. Anim. Sci.89(E-Suppl.):359. Daisuke Takahashi, Yunjeong Kim, Kyeong-Ok Chang, Asokan Anbanandam, Om Prakash. Structural and dynamic characterization of Norwalk virus protease. GRASP 2011 NMR meeting, Lawrence, KS, 2011. Yunjeong Kim, Daisuke Takahashi, Om Prakash, Kyeong-Ok Chang. Enzyme assay and NMR studies of the norovirus proteases. American Society for Virology, 2011. Daisuke Takahashi, Yunjeong Kim, Kyeong-Ok Chang, Asokan Anbanandam, Om Prakash. NMR Solution structure determination of Norwalk virus 3C-like cysteine protease. The 55th Biophysical Soc Meeting, Baltimore, MD, 2011.
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Progress 01/01/10 to 12/31/10
Outputs
OUTPUTS: We have used an interdisciplinary team approach to generate important outputs on several enteric bacteria and viruses in livestock and food products. Activities include a survey of beef producers on BVDV biosecurity practices, development of methods for detecting and characterizing enteric pathogens, development of models for controlling enteric bacteria and viruses, development of biodegradable nanogels for oral delivery of interferon, and field studies of Salmonella, Shiga-toxin producing E. coli (STEC), Enterococcus and BVDV in cattle and swine production systems as well as studies of these bacteria in food and livestock feed. We have developed a multiplex real-time PCR for quantification of E. coli O157 and other multiplex PCR procedures for detection of seven serotypes of STEC in bovine feces. We also have generated new applied knowledge on the transmission, dissemination, persistence and survival of enteric bacterial and viral pathogens in food and food animal production environments. We used experimental approaches to demonstrate that BVDV transmission from persistently infected (PI) cattle to non-PI cattle can result in transient infections that may not lead to overt clinical disease, but could lead to further transmission of BVDV. We have studied the ability of common insect species to acquire and transfer enteric bacteria in food and livestock feed systems. We have utilized modeling techniques to evaluate preharvest interventions for E. coli O157 contamination of beef cattle carcasses and to quantify the value of implementing whole herd BVDV testing strategies in beef cow-calf herds. We also have generated new applied knowledge on potential effects of feed ingredients on E. coli O157 fecal shedding in finishing cattle and on fecal enterococci in feeder pigs. We also have studied norovirus structures and vehicles for oral delivery of interferon in norovirus infections. We have mentored multiple veterinary students and graduate students in veterinary pathobiology, public health, food science programs. We have delivered manuscripts as well as oral and poster presentations of the results of these studies to the scientific community and industry representatives at several regional, national, and international scientific meetings. In addition, press releases have been used to disseminate the important research outcomes to a broader audience. PARTICIPANTS: Principal Investigators: David G. Renter (Station Rep), Kyeong-Ok Chang, T.G. Nagaraja, Sanjeev Narayanan, Jerome Nietfeld, Dick Oberst, Ludek Zurek. Collaborators: Mike Sanderson, H. Morgan Scott, Dan Thomson, Jim Drouillard, Xiaorong Shi, Jianfa Bai. Students and post-doctoral fellows: Chuck Dodd, Trent Fox, Megan Jacob, Ethel Taylor, Callie Walker, B. Fritz, M. Jahangir Alam, Greg Peterson, R. Amachawadi, D. Mina, A. Thornton, J. Nickell, B. Depenbusch. TARGET AUDIENCES: Veterinarians, researchers, scientific extension personnel, cattle producers, industry organizations, animal scientists, and the general public. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
Members of our group have demonstrated multiple useful outcomes associated with E. coli O157:H7, other STEC, Salmonella, and antimicrobial resistance of enteric bacteria; primarily in beef cattle production systems, but also in swine and food production environments. We also have generated multiple useful outcomes associated with viral pathogens; specifically, on the transmission and potential control opportunities for BVDV in cattle, and potential antiviral strategies for noroviral infections. The multiplex PCR procedures that we have developed for serotypes of STEC in bovine feces may be extremely useful for identifying, quantifying and/or characterizing these important enteric bacteria. Our research outcomes on Salmonella in feedlot populations are unique and may facilitate approaches to controlling Salmonella in commercial feedlots. Our research also has demonstrated that the speed with which exposed cattle become transiently infected and their potential ability to shed the virus may impact design and implementation of BVDV control programs. By demonstrating that the Red Flour Beetle, Tribolium castaneum, can acquire antibiotic-resistant enterococci from animal feed and transfer them to sterile feed, we show that management of T. castaneum may be important to prevent the spread of antibiotic-resistant and virulent enterococci in animal feed and feed manufacturing environments. Similar implications could result from our findings that stored-product insects carry antibiotic-resistant and potentially virulent enterococci. We also have shown that their dispersal behavior and capacity to transport antibiotic-resistant bacteria make house flies a potential threat to public health; thus, area wide management may be needed to mitigate health risks. We also have produced outcomes that may impact interventions for reducing foodborne enteric bacteria and viruses. We have shown that combinations of preharvest interventions may be particularly important for supplementing harvest interventions during periods of higher variability in fecal shedding prevalence (i.e., summer). We also have produced outcomes that may be extremely useful for optimizing BVDV testing strategies for cow-calf herds. By evaluating data from a state BVDV program, we have generated information that may impact potential client education needs for reducing herd exposures to BVDV. Our work on norovirus has produced novel outcomes on issues that may impact therapy for norovirus infections.
Publications
- Paddock ZD, Walker CE, Drouillard JS, Renter DG, Nagaraja TG. 2010. Monensin level, supplemental urea, and administration of ractopamine on fecal shedding of Escherichia coli O157:H7 in feedlot cattle. National Meeting of the American Society of Animal Science, Denver. J Anim Sci. 88 (E-Suppl. 2): 1086.
- Nickell JS, White BJ, Renter DG, Larson RL, Anderson G, Oberst R, Hesse R, Munoz R. 2010. El-Attrache J. Utilization of VetMAX Gold BVDV Detection Kit for the detection and potential differentiation of persistently infected and transiently infected cattle. European Diagnostics Association, Lelystad, Holland.
- Yunjeong Kim, Mahendra Thapa, Duy H Hua and K.O. Chang. 2010. Biodegradable nanogels as delivery systems for interferons in norovirus infection. The 29th Annual meeting of American Society for Virology, Bozeman, Montana, July 17-21.
- Daisuke Takahashi, Yunjeong Kim, Kyeong-Ok Chang, Asokan Anbanandam, Om Prakash. 2010. NMR Structural Studies on Norwalk Virus 3C-like Cysteine Protease. Great Plains Regional Annual Symposium on Protein and Biomolecular NMR, Lawrence, KS, Oct 29-30.
- K. Jung, Wang, Q.H., Zhang, Z., Takanashi, S., Scheuer, K., Shen, S., Kim, Y., Chang, K.O., Saif, L.J. 2010. Simvastatin enhances GII.4 human norovirus infectivity in gnotobiotic pigs. 4th International Meeting on Calicivirus. Santa Cruz, Chile, Oct 16-19.
- Jacob, M. E., K. F. Lechtenberg, L. L. Burnham, D. Haverkamp, and T. G. Nagaraja. 2010. Feeding MSE direct-fed microbials in finishing cattle decreases the fecal shedding of Escherichia coli O157:H7. Midwest American Society of Animal Sciences Meeting, Iowa. Mar 15-17. Jacob, M. E., D. G. Renter, Z. D. Paddock, K. F. Lechtenberg, and T. G. Nagaraja. 2010. Feeding dried or wet distillers grains at varying inclusion levels to feedlot cattle affects the fecal prevalence of Escherichia coli O157:H7. Midwest American Society of Animal Sciences Meeting, Iowa. Mar 15-17.
- Amachawadi, R. G., N. W. Shelton, X. Shi, S. S. Dritz, M. D. Tokach, J. L. Nelssen, S. K. Narayanan, L. Zurek, H. M. Scott, and T. G. Nagaraja. 2010. Effect of copper supplementation on prevalence of transferable copper resistance (tcrB) gene among fecal enterococci in piglets. Second ASM Conference on Antimicorbial Resistance in Zoonotic Bacteria and Foodborne Pathogens in Animals, Humans, and the Environment, Toronto, Canada. June 8-11.
- Amachawadi, R. G., J. Vinasco, X. Shi, H. M. Scott, and T. G. Nagaraja. 2010. Conjugal transfer of acquired copper resistance (tcrB) gene in fecal enterococci of pigs. Third ASM Conference on Enterococci, Portland, OR. July 30-Aug 2.
- Rao S, Van Donkersgoed J, Bohaychuk V, Besser T, Song X, Wagner B, Hancock D, Renter DG, Dargatz D, Morley P. 2010. Antimicrobial drug use and antimicrobial resistance in enteric bacteria among cattle from Alberta feedlots. Foodborne Pathog and Dis. 7(4):449-457.
- Nickell JS, White BJ, Larson RL, Renter DG. 2010. Onset and duration of transient infections among antibody diverse beef calves exposed to a Bovine Viral Diarrhea Virus persistently infected calf. Inter J Appl Res Vet Med. 8(4) in press.
- Smith R, Sanderson MW, Renter DG, White B, Larson R. 2010. A stochastic risk analysis model for the spread of Bovine Viral Diarrhea Virus after introduction to naive cow calf herds. Prev Vet Med. 95(1-2): 86-98.
- Jacob M, Paddock Z, Renter DG, Lechtenberg K, Nagaraja TG. 2010. Feeding dried or wet distillers grains at various inclusion levels to feedlot cattle affects fecal shedding of Escherichia coli O157:H7. Appl and Environ Microbiol. 76(21): 7238-7242.
- Jacob M, Renter DG, Nagaraja TG. 2010. Animal and truckload level associations between E. coli O157:H7 in feces and on hides at harvest and contamination of pre evisceration beef carcasses. J Food Protec. 73(6): 1030-1037.
- Dodd C, Renter DG, Fox J, Shi X, Sanderson MW, Nagaraja TG. 2010. Genetic relatedness of Escherichia coli O157 isolates from cattle feces and pre-intervention beef carcasses. Foodborne Pathog and Dis. 7(4): 357-365.
- Taylor E, Kastner J, Renter DG. 2010. Challenges involved in the Salmonella Saintpaul outbreak and lessons learned. J Public Health Manag and Pract. 16(3): 221-231.
- Walker, C. X. Shi, M. J. Sanderson, J. S. Sargeant, and T. G. Nagaraja. 2010. Prevalence of Escherichia coli O157:H7 in gut contents of beef cattle at slaughter. Foodborne Pathog and Dis. 7: 249-255.
- Jacob, M.E., J.T. Fox, T.G. Nagaraja, J.S. Drouillard, R.G. Amachavadi, S.K. Narayanan. 2010. Effects of feeding elevated concentrations of supplemental copper and zinc on antimicrobial susceptibilities of fecal bacteria in feedlot cattle. Foodborne Pathog and Dis. 7:643-648.
- Jacob M. E., D. G. Renter, and T. G. Nagaraja. 2010. Animal- and truckload-level associations between E. coli O157:H7 in feces and on hides at harvest and contamination of pre-evisceration beef carcasses. J. Food Prot. 73:1030-1037.
- Bai J., X. Shi and T. G. Nagaraja. 2010. A Multiplex PCR Procedure for detection of six major virulence genes in Escherichia coli O157:H7. J. Microbiol. Meth. 82:85-89.
- Amachawadi, R. G., N. W. Shelton, M. E. Jacob, X. Shi, S. K. Narayanan, L. Zurek, S. S. Dritz, J. L. Nelssen, M. D. Tokach, and T. G. Nagaraja. 2010. Occurrence of tcrB, a transferable copper resistance gene, in fecal enterococci of swine. Foodborne Pathog and Dis. 9:1089-1097.
- Channaiah LH, Subramanyam B, Zurek L. 2010. Survival of Enterococcus faecalis OG1RF:pCF10 in poultry and cattle feed: vector competence of the Red Flour Beetle, Tribolium castaneum (Herbst). J Food Protect. 73(3): 568-573.
- Channaiah LH, Subramanyam B, McKinney, and Zurek L. 2010. Stored-product insects carry antibiotic-resistant and potentially virulent enterococci. FEMS Micro Ecol. 74(2): 464-471. Chakrabarti S, Kambhampati S, Zurek L. 2010. Assessment of house fly dispersal between rural and urban habitats in Kansas, USA. J Kansas Entomol Soc. 83(2): 172-188.
- Jacob, Megan. 2010. The Effect of Distillers Grains on the Prevalence and Concentration of Escherichia coli O157 in Cattle. PhD Dissertation, Kansas State University. (Advisor, T.G. Nagaraja).
- Dodd, Chuck. 2010. Epidemiology of Salmonella and E. coli O157 in Beef Cattle Production Systems. PhD Dissertation, Kansas State University. (Advisor, D.G. Renter).
- Amachawadi, R. G. 2010. Effects of feeding elevated concentration of copper on prevalence and selection of fecal enterococci positive for transferable copper resistance gene in piglets. MS thesis, Kansas State University. (Advisor, T.G. Nagaraja).
- Y. Kim and K.O. Chang. 2010. Chapter 6. Porcine enteric caliciviruses. Caliciviruses: Molecular and Cellular Virology. Horizon Scientific Press.
- K.O. Chang and Y. Kim. 2010. Chapter 9. Reverse Genetics System and Replicon system of Caliciviruses: Molecular and Cellular Virology. Horizon Scientific Press.
- Nickell JS, White BJ, Larson RL, Renter DG, Sanderson MW. 2010. Estimating the value of implementing whole herd bovine viral diarrhea virus (BVDV) testing strategies in U.S. cow-calf herds when BVDV herd status is unknown. American Association of Veterinary Laboratory Diagnosticians Annual Meeting, Minneapolis, MN.
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Progress 01/01/09 to 12/31/09
Outputs
OUTPUTS: We've used an interdisciplinary team approach to address Objectives 1 and 2 of this project through research on enteric bacteria. We improved on methods for detection and characterization of bacteria by developing a microarray chip and software analysis platform that allows for rapid identification of human and animal bacterial pathogens in complex sample matrices including soil and feces, and by developing a multiplex PCR procedure that detected six of E. coli O157:H7's major virulence genes, fliC, stx1, stx2, eae, rfbE, and hlyA, in a single reaction. We also evaluated the phenotypic and genotypic characteristics of E. coli O157:H7 isolates in order to better evaluate the epidemiologic factors related to transmission of E. coli O157:H7 from live cattle to carcasses and the microbiologic factors that may be related to the propensity for cattle strains to cause human disease. We've provided evidence that catecholamine hormones affect horizontal gene transfer rates between enteric bacteria and affect growth and virulence gene expression in Citrobacter rodentium. We also have shown that oxytetracycline dosing does not appear to affect transfer of a plasmid containing antimicrobial resistance genes among Salmonella and E. coli. Our research team has provided the first report of the tcrB gene in fecal enterococci of U.S. swine, which may have antimicrobial resistance implications. We've continued to provide data on potential intervention strategies for enteric bacteria in cattle. We demonstrated the efficacy of an SRP-based vaccine for E. coli O157:H7, which may prove to be a preharvest intervention that reduces E. coli O157:H7 in cattle and ultimately improve food safety. However, our commercial feedlot trial of the conditionally licensed and commercially available Salmonella Newport SRP vaccine showed that the vaccine had no significant effect on Salmonella fecal prevalence, cattle health, or cattle performance. We've continued to generate quantitative effect estimates for factors associated with E. coli O157:H7 fecal shedding and contamination of beef hides and carcasses so that we might improve the development or implementation of effective intervention strategies. In addition, we have evaluated, and will continue to evaluate the association between feeding distiller's grains (DG) and increased fecal shedding of E. coli O157:H7 in finishing cattle. We confirmed the positive association, and showed that the inclusion level (20 vs. 40 percent) but not the type of DG (dry vs. wet) affects fecal prevalence of E. coli O157:H7. This may explain why we found no effects on several measures of E. coli O157:H7 prevalence in an observational study of cattle (fed various levels and types of DG) that were presented to a commercial abattoir. We have delivered oral and poster presentations of the results of these studies to the scientific community and industry representatives at several regional, national, and international scientific meetings (please see publications). In addition, press releases have been used to disseminate the important research outcomes to a broader audience. PARTICIPANTS: Principal Investigators: David G. Renter (Station Rep), T.G. Nagaraja, Sanjeev Narayanan, Ludek Zurek, Dick Oberst, Jerome Niedfeldt Collaborators: Dan Thomson, Mike Sanderson, Jim Drouillard, Xiaorong Shi, Jianfa Bai Students and post-doctoral fellows: Chuck Dodd, Trent Fox, Megan Jacob, Ethel Taylor, Callie Walker, B. Fritz, M. Jahangir Alam, Greg Peterson, R. Amachawadi, D. Mina, A. Thornton, S. Sreerama, B. Depenbusch TARGET AUDIENCES: Veterinarians, researchers, scientific extension personnel, cattle producers, industry organizations, animal scientists, and the general public PROJECT MODIFICATIONS: Not relevant to this project.
Impacts
We developed a microarray chip and software analysis platform that allows for molecular identification of bacterial pathogens with high specificity and reliability that is capable of detecting pathogens in complex sample matrices. We also developed a multiplex PCR procedure that detects six major virulence genes in E. coli O157:H7, which is useful because previous procedures required multiple PCR reactions to detect all six genes. We also characterized O157:H7 isolates to show the important risk factors potentially influencing transmission and spread of E. coli O157:H7 from cattle to carcasses and to determine factors associated with Shiga toxin production that may serve as useful markers to identify strains of E. coli O157:H7 that are most likely to cause human disease. We also developed important information on factors affecting E. coli O157:H7 at harvest, which may help to target pre-harvest intervention strategies for E. coli O157:H7. Our work on effects of catecholamine hormones on gene transfer rates between enteric bacteria and on Citrobacter rodentium growth and gene expression are important because results provide an explanation of how host factors may drive development of virulent and multidrug resistant strains of enteric bacteria, and how stress may influence the duration and severity of disease. We also have shown pharmacokinetic measures related to oxytetracycline dosing do not appear to affect transfer plasmids containing antimicrobial resistance genes. One of our studies was the first to report the tcrB gene in fecal enterococci of U.S. swine, which is important because of the potential association between tcrB and resistance to antibiotics, and because of the propensity of enterococci to transfer tcrB and antibiotic resistance genes to other bacteria. We developed useful information on the field efficacy of a vaccine technology that utilizes the iron requirement of pathogenic bacteria by targeting siderophore receptor and porin proteins (SRP). We found that an anti-Escherichia coli O157 SRP-based vaccine reduced fecal shedding of E. coli O157:H7 in feedlot cattle. These results and others indicate that this vaccine may serve as an effective intervention to reduce O157:H7 on cattle presented for slaughter and ultimately improve food safety. A commercially available Salmonella SRP vaccine could stimulate immunity and provide cross-protection to multiple Salmonella serotypes that are important to public health and cattle health and production. However, our study (in one commercial feedlot) showed the vaccine had no significant effect on Salmonella fecal prevalence, cattle health, or cattle performance. Feeding distiller's grains (DG) has been associated with increased fecal shedding of E. coli O157:H7 in finishing cattle. Our recent experimental trial confirmed that positive association, and showed that the inclusion level (20 vs. 40 percent) but not the type of DG (dry vs. wet) affects fecal prevalence of E. coli O157:H7. This may explain why we found no effects on prevalence estimates of E. coli O157:H7 in an observational study where cattle were fed various levels and types of DG.
Publications
- Alam M.J., Renter D.G., Taylor E.V., Mina D.M., Moxley R.A., Smith D.R. 2009. Antimicrobial susceptibility profiles of Salmonella enterica serotypes recovered from pens of commercial feedlot cattle using different sampling approaches. Current Microbiology 58(4): 354-359.
- Van Donkersgoed, J., Bohaychuk V., Besser T., Song X., Wagner B., Hancock D., Renter D.G., Dargatz D. 2009. Occurrence of foodborne bacteria in Alberta feedlots. Canadian Veterinary Journal; 50(2): 166-172.
- Coolon J.D., Jones K.L., Narayanan S., Wisely S.M. 2009. Microbial Ecology of the Intestinal Flora of P. maniculatus and P. leucopus of the Tri-State Mining District. Molecular Ecology, in press.
- Reinstein S., Fox J.T., Shi X., Alam M.J., Renter D.G., Nagaraja T.G. 2009. Prevalence of Escherichia coli O157:H7 in organically and naturally raised beef cattle. Applied and Environmental Microbiology ; 75(16): 5421-5423.
- Alam M.J., Renter D.G., Ives S.E., Thomson D.U., Hollis L.C., Sanderson M.W., Nagaraja T.G. 2009. Potential associations between fecal shedding of Salmonella in feedlot cattle treated for apparent respiratory disease and subsequent adverse health outcomes. Veterinary Research 2009; 40:02.
- Jacob M.E., Fox J.T., Drouillard J.S., Renter D.G., Nagaraja T.G. 2009. Evaluation of feeding dried distillers grains with solubles and dry-rolled corn on the fecal prevalence of Escherichia coli O157:H7 and Salmonella spp. in cattle. Foodborne Pathogens and Disease; 6(2): 145-153.
- Peterson G., Bai J., Narayanan S. 2009. A co-printed oligomer to enhance reliability of spotted microarrays. J Microbiol Methods; 77(3): 261-266.
- Fox, J. T., Drouillard, J. S., and Nagaraja T. G. 2009. Competitive exclusion Escherichia coli cultures on E. coli O157 batch culture ruminal or fecal microbial fermentation. Foodborne Pathogens and Disease; 6:193-199.
- Thomson D. U., Loneragan, G. H., Thornton A. B., Lechtenberg K. F., Emery D. A., Burkhardt D. T., Nagaraja T. G. 2009. Use of a siderophore receptor and porin proteins-based vaccine to control the burden of Escherichia coli O157:H7 in feedlot cattle. Foodborne Pathogens and Disease 2009; 6:871-877.
- Fox, J. T., Thomson, D. U., Drouillard J. S., Thornton, A. B., Burkhardt D. T., Emery D. A., Nagaraja T. G. 2009. Efficacy of Escherichia coli O157:H7 siderophore receptor/porin proteins-based vaccine in feedlot cattle naturally shedding E. coli O157. Foodborne Pathogens and Disease 2009; 6:893-899.
- Jacob, M. E., Callaway T. R., Nagaraja T. G. 2009. Dietary interactions and interventions affecting Escherichia coli O157 colonization and shedding in cattle. Foodborne Pathogens and Disease 6:785-792.
- Taylor, Ethel. 2009. Foodborne disease in the United States: from surveillance to policy. MPH, Report. (Advisor, D.G. Renter)
- Lubbers, Brian. 2009. The Impact of Oxytetracycline Dosing on Bacterial Populations and Transfer of Resistance Elements between Salmonella and E. coli in Vitro and in Vivo. Ph.D. Dissertation. (Minor Advisor: S. Narayanan).
- Renter, David G. 2009. (invited presentation). E. coli O157:H7 - Dissemination and Persistence in Bovine Production Environments. The Third Governors Conference on Ensuring Food Safety: E. coli O157:H7 -progress and challenges. University of Nebraska-Lincoln.
- Nagaraja, T. G. 2009. (invited presentation). Feeding Distillers Grains to Ruminants: What do we know so far The Third Governors Conference on Ensuring Food Safety: E. coli O157:H7 - progress and challenges. University of Nebraska-Lincoln.
- Renter D.G., Dodd, C.C., Thomson D.U., Nagaraja T.G. 2009. Salmonella in beef cattle production systems. BIFSCO - Beef Industry Safety Summit, San Diego CA.
- Dodd, C.C., Renter D.G., Thomson D.U., Nagaraja T.G. 2009. A randomized trial assessing effects of a commercially available Salmonella vaccine in commercial feedlot cattle. Conference for Research Workers in Animal Disease, Chicago, IL. #64.
- Dodd, C.C., Renter D.G., Nagaraja T.G., Shi X. 2009. Prevalence and persistence of Salmonella within pens of feedlot cattle. Conference for Research Workers in Animal Disease, Chicago, IL. #44.
- Fox, J. T., Drouillard J. S., Nagaraja T. G. 2009. Effects of mucin and its carbohydrate constituents on Escherichia coli O157 in batch culture fermentations with ruminal or fecal microbial inoculums. Journal of Animal Science 2009; 87:1304-1313.
- Thornton, A. B., Thomson D. U., Fox J. T., Loneragan G. H., Burkhardt D. T., Emery D. A., Nagaraja T G. 2009. Siderophore receptor/porin proteins-based vaccination reduces prevalence and shedding of Escherichia coli O157:H7 in experimentally inoculated cattle. Journal of Food Protection 2009; 72:866-869.
- Peterson, G, Bai, J., Nagaraja, T.G., Patton, J., and Narayanan.S. 2009. Diagnostic Microarray for Human and Animal Bacterial Diseases. Conference for Research Workers in Animal Disease, Chicago, IL.
- Peterson, G., and Narayanan, S. 2009. Norepinephrine Increases Horizontal Gene Transfer Rates Between Enteric Bacteria. Conference for Research Workers in Animal Disease, Chicago, IL.
- Gart, E., and Narayanan, S. 2009. Influence of variable concentration of catecholamines on the growth of Citrobacter rodentium and expression of virulence genes. Conference for Research Workers in Animal Disease, Chicago, IL.
- Nagaraja, T. G. 2009. Pathogen concerns for organically-grown beef. Symposium on organic poultry and red meats-microbiology considerations: What do we know, what more do we need to know and how do we get there Institute of Food Technology Annual Meeting, Anaheim, CA.
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Progress 01/01/08 to 12/31/08
Outputs
OUTPUTS: Under Objective 1 (Focus on emerging diseases - Identify, characterize, and develop improved detection methods related to newly recognized novel or emerging causes of enteric diseases and enteric pathogens of cattle and swine), we have conducted two natural prevalence studies in feedlot cattle and one inoculation study in calves that have all shown a positive association between feeding distillers' grains (DG) and fecal shedding of E. coli O157:H7 in cattle. Additionally, we have conducted in vitro fermentation studies to evaluate the effects of DG on growth of E. coli O157:H7. We have also conducted a study that evaluated the genetic variation and Shiga toxin production of E. coli O157:H7 isolates from bovine and human feces. In addition, two separate studies were used to develop a multiplex PCR for identification of E. coli O26, O111, O103, O157, and O145 in cattle feces, and microarray and multiplex PCR assays for serotype and identification of virulence genes in Salmonella enterica of human or animal origin. We also conducted a study that assessed the antimicrobial susceptibility profiles of Salmonella enterica serotypes recovered from pens of commercial feedlot cattle using different types of composite samples. Under Objective 2 (Focus on effective interventions - Develop and improve interventions and preventative measures to reduce the incidence and prevalence of infections of cattle and swine with enteric and food borne disease agents), we conducted a cattle inoculation study evaluating the efficacy of a vaccine containing outer membrane siderophore receptor and porin (SRP) proteins in reducing prevalence of E. coli O157:H7. We are currently conducting a study evaluating effect of the Salmonella SRP vaccine on prevalence of Salmonella in feces of commercial feeder cattle, and on disease outcomes and performance measures in the feedlot. We have delivered oral and poster presentations of the results of these studies to the scientific community and industry representatives at several regional, national, and international scientific meetings (please see publications). In addition, press releases have been used to disseminate the important research outcomes to a broader audience. PARTICIPANTS: Principal Investigators: Dick Oberst, T.G. Nagaraja, Jerome Niedfedlt, David G. Renter (Station Rep), Ludek Zurek, Don Robertson Collaborators: Sanjeev Narayanan, Dan Thomson, Mike Sanderson, Jim Drouillard, Xiaorong Shi, Jianfa Bai Students and post-doctoral fellows: Trent Fox, Megan Jacob, Ethel Taylor, Callie Walker, B. Fritz, Jahangir Alam, Greg Peterson, R. Amachawadi, D. Mina, A. Thornton, S. Sreerama, D. Hermesch, B. Depenbusch TARGET AUDIENCES: Veterinarians, researchers, scientific extension personnel, cattle producers, industry organizations, animal scientists, and the general public. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
Our results have led to new knowledge on factors associated with fecal shedding of E. coli O157:H7 in cattle that could lead to important interventions that decrease the economic and health impacts. We've shown that feeding distillers' grain, an ethanol fermentation co-product and valuable cattle feed, can increase fecal shedding of E. coli O157. We've also shown that E. coli O157 prevalence in pens immediately prior to slaughter can be quite high or very low even within feedlots and seasons. Factors such as month, temperature, precipitation, pen floor conditions, and water tank cleanliness were associated with E. coli O157. Methods such as ROPES that are associated with fecal and hide prevalence may provide advantages to efficiently classify pens as high or low risk to food safety. We've also found that carcass contamination was associated with truckload-level measures of fecal E. coli O157, particularly whether or not a high shedder was present within the truckload; suggesting these cattle could be a potential target for mitigation strategies to reduce carcass contamination. We've found that many Salmonella isolates collected within a feedlot pen were similar in terms of serotype and antimicrobial susceptibility regardless of the sample type. However, multi-drug resistant Salmonella and rare serotypes were recovered too infrequently to suggest a general strategy for detection and monitoring. In a different study, our results indicated a high prevalence of Salmonella in a population of cattle treated for apparent respiratory disease, but that effects associated with clinical outcomes may depend on the Salmonella strain. We've developed a multiplex PCR for identifying E. coli O26, O111, O103, O157, and O145, which will be ideal for rapid and reliable screening of samples for presence of these serotypes, and for serotype determination of isolates from bacteriological analysis. We've also developed assays for serotype and identification of virulence genes in Salmonella. An additional multiplex PCR increased the number of identifiable serotypes and provided an identication of the pathogenicity of isolates. We've also found that a TNP region appears to be a predictor of non-toxin producing strains for bovine E. coli O157:H7 isolates than for human isolates. However, Q933 was a strong indicator for high Stx2 production for both human and bovine strains and may be a useful screening tool to assess potential human virulence. Our results also have provided useful information on effective interventions for Salmonella and E. coli O157 in cattle. The efficacy of a SRP vaccine for E. coli O157 was documented in cattle inoculated with E. coli O157:H7 and in naturally shedding feedlot cattle. The SRP vaccine appears to be effective in reducing prevalence and fecal concentration of E. coli O157 and could be a very valuable pre-harvest intervention. We also found that administration of a Salmonella Newport SRP may increase milk production, even in cattle without detectable shedding of Salmonella Newport or clinical signs of salmonellosis.
Publications
- Jacob, M. E., J. T. Fox, S. L. Reinstein, and T. G. Nagaraja*. 2008. Antimicrobial susceptibility of foodborne pathogens in organic or natural production systems: an overview. Foodborne Pathog Dis. 5:721-730.
- Fox, J. T., D. G. Renter*, M. W. Sanderson, A. L. Nutsch, X. Shi, and T. G. Nagaraja. 2008. Associations between the presence and magnitude of Escherichia coli O157 in feces at harvest and contamination of preintervention beef carcasses. J. Food Protect.71:1761-1767.
- Jacob, M. E., J. T. Fox, J. S. Drouillard, D. G. Renter, and T. G. Nagaraja*. 2008. Effects of dried distillers grain on fecal prevalence and growth of Escherichia coli O157 in batch culture fermentations from cattle. Appl. Environ. Microbiol. 74: 38-43.
- Fox, J. T., X. Shi, and T. G. Nagaraja*. 2008. Escherichia coli O157 in the rectoanal mucosal region of cattle. Foodborne Path. Dis. 5:69-77.
- Depenbusch, B. E., T. G. Nagaraja, J. M. Sargeant, J. S. Drouillard*, E. R. Loe, and M. E. Corrigan. 2008. Influence of processed grains on fecal pH, starch concentration, and shedding of Escherichia coli O157 in feedlot cattle. J. Anim. Sci. 86:632-639.
- Renter D.G. 2008. Hemolytic Uremic Syndrome, In: Diseases of the Renal System. Large Animal Internal Medicine 4rd edition; 2008. Bradford P. Smith, Editor. pg. 965.
- Renter D.G., Smith D.R., King R., Stilborn B., Berg J., Berezowski J., McFall M. 2008. Detection and determinants of Escherichia coli O157:H7 in pre-slaughter feedlot pens in Alberta. Canadian Journal of Veterinary Research; 72(3):217-227.
- Hermesch D.R., Thomson D.U., Loneragan G.H., Renter D.G., White B.J. 2008. Effects of a commercially available SRP Salmonella Newport vaccine on milk production, somatic cell count and Salmonella shedding in dairy cows with no clinical signs of salmonellosis. American Journal of Veterinary Research 69(9):1229-1234.
- Alam M.J., Renter D.G., Ives S.E., Thomson D.U., Hollis L.C., Sanderson M.W., Nagaraja T.G. 2009. Potential associations between fecal shedding of Salmonella in feedlot cattle treated for apparent respiratory disease and subsequent adverse health outcomes. Veterinary Research; 40:02.
- Fox, J. T., S. Reinstein, M. E. Jacob, and T. G. Nagaraja*. 2008. Niche marketing production practices for beef cattle in the United States and prevalence of foodborne pathogens. Foodborne Path. Dis. 5:559-569.
- Jacob, M. E., J. T. Fox, S. K. Narayanan, J. S. Drouillard, D. G. Renter, and T. G. Nagaraja*. 2008. Effects of feeding wet corn distillers grains with solubles with or without monensin and tylosin on the prevalence and antimicrobial susceptibilities of fecal food-borne pathogenic and commensal bacteria in feedlot cattle. J. Anim. Sci. 86: 1182-1190.
- Jacob, M. E., G. L. Parsons, M. K. Shelor, J. T. Fox, J. S. Drouillard, D. U. Thomson, D. G. Renter, and T. G. Nagaraja*. 2008. Feeding supplemental dried distillers grains increases fecal shedding of Escherichia coli O157 in experimentally inoculated calves. Zoonoses Publ. Hlth. 55:125-132.
- Sreerama, S., M.W. Sanderson*, M. Wilkerson, and T.G. Nagaraja. 2008. Impact of persistent bovine viral diarrhea viral infection on the duration and level of shedding of Escherichia coli O157:H7 in calves. Foodborne Path. Dis. 5: 245-251.
- Sreerama, S., M.W. Sanderson*, M. Wilkerson, and T.G. Nagaraja. 2008. Impact of dexamethasone induced immunosuppression on the duration and level of shedding of E. coli O157:H7 in calves. Curr. Microbiol. 56:651-655.
- Bai, J., X. Shi and T. G. Nagaraja. 2008. An improved multiplex PCR method to detect eae, stx1, stx2, fliC, and hlyA in Escherichia coli O157:H7. Poster presented at the 108 th General Meeting of the American Society for Microbiology, Boston, MA., June 1-5.
- Jacob, M. E., J. S. Drouillard, D. G. Renter, J. T. Fox, and T. G. Nagaraja. 2007. Effects of distillers grain and dry-rolled corn supplementation in steam-flaked corn grain-based diets on fecal shedding of Escherichia coli O157:H7 and Salmonella. J. Anim. Sci., 86(Supp 1): 26.
- Nagaraja, T. G., D. G. Renter, M. E. Jacob, M. J. Sanderson, and D. O. Thomson. 2008. The impact of dietary distillers grains on Escherichia coli O157:H7 in cattle and interventions to reduce the potential food safety impact. Poster presented in the Food safety and Epidemiology and Epidemiological approaches for food safety principal investigator meeting, Washington, DC, Nov 18-19.
- Taylor, E., X. Shi, J. Alam, G. Peterson, S. Narayanan, D. Renter, and T. G. Nagaraja. 2008. Genetic variation and Shiga toxin production of Escherichia coli O157:H7 isolates from bovine and human feces. (Abstract # 48P). Poster presented in the 2008 Conference of Research Workers on Animal Diseases, Chicago, IL., (Dec 7-9, 2008).
- Amachawadi, R., M. Jacob, N. Shelton, C. Lakshmikantha, X. Shi, L. Zurek, S. Narayanan, M. Tokatch,, J. Nelson, and T. G. Nagaraja. 2008. Occurrence of tcrB, a transferable copper resistance gene, in fecal enterococci of swine. (Abstract # 78). Oral presentation in the 2008 Conference of Research Workers on Animal Diseases, Chicago, IL., (Dec 7-9, 2008).
- Jacob, M. E., D. G. Renter, and T. G. Nagaraja. 2008. Evaluating methods for detecting Salmonella in fecal and carcass samples using Bayesian analysis (Abstract # 81). Oral presentation in the 2008 Conference of Research Workers on Animal Diseases, Chicago, IL., (Dec 7-9, 2008).
- Fritz, B., G. Peterson, T. G. Nagaraja, and S. Narayanan. 2008. Development of multiplex PCR for identification of E. coli O26, O103, O111, O145, and O157 in cattle feces. (Abstract # 95). Oral presentation in the 2008 Conference of Research Workers on Animal Diseases, Chicago, IL., (Dec 7-9, 2008).
- Peterson, G., B. Gerdes, J. Berges, T. G. Nagaraja, J. G. Frye, D. S. Boyle, and S. Narayanan. 2008. Development of multiplex PCR for identification of E. coli O26, O103, O111, O145, and O157 in cattle feces. (Abstract # 95). Oral presentation in the 2008 Conference of Research Workers on Animal Diseases, Chicago, IL., (Dec 7-9, 2008).
- Walker, Callie. 2008. Prevalence of Escherichia coli O157 in beef cattle. M. S. Thesis, Kansas State University.
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