Progress 10/28/16 to 09/30/20
Outputs
Target Audience:Upon initiation of this project, the target audience was food animal producers and the veterinarians who work with them. Our initial intent was to use the food animal pastures and facilities of the Auburn University College of Veterinary Medicine (AU-CVM) to investigate Salmonellamovement between animal species. One year into the project we realized that our findings also needed to be shared with administrators at the vet school, including the Director of the Teaching Hospitals, the Head of the Food Animal Section, the Head of the Equine Section, and the veterinarian in charge fo the AU-CVM dairy herd. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?Both objectives of this project formed the core work of a Masters' thesis project for graduate student Steven Kitchens in the PI's laboratory. Two undergraduate students, Austin Conley and Ryan Valentino, each enrolled in Research Problems courses with the PI and generated data for Objective 2. The ERCSalmonellasampling and initial bacteriophage isolation efforts described here composed the core of Mackenzie Michael's undergraduate research project for her enrollment in VBMS 4980 - Undergraduate Research. This graded course required Mackenzie to learn and carry out a set of research protocols, to analyze the results of her research, to write a paper describing her project, and to formally present her findings to a diverse audience. Ph.D. graduate student Steven Kitchens adapted the culture protocol for environmental isolation of Salmonella and developed the sampling technique utilized in Objectives 1 to generate the data described. Co-investigator Wright worked with Steven on designing statistical analyses designed to determine the significance of our data. Steven has since presented his data to a broad audience of students and faculty at the AU-CVM's annual Phi Zeta Research Emphasis Day. How have the results been disseminated to communities of interest?From the project's outset, the PI sent quarterly reports to the AU-CVM Hospital Director and the heads of the food animal and equine sections of the Large Animal Teaching Hospital. Undergraduate and graduate students involved with the project regularly presented their research findings to a diverse audience at local and regional scientific meetings. The graduate students gave annual departmental seminars throughoutthe life of the project. And the PI briefedmembers of the AU Food Systems Institute'sSalmonellaWorking Group frequently as the project unfolded. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
Objective 1: Trace movement ofSalmonellastrains among the Auburn University College of Veterinary Medicine's (AU-CVM) equine, beef, and dairy barns, and with associated pastures and natural water sources. Major Activities Completed/Experiments Conducted: i.) Two protocols were developed to address Objective 1: (a) an environmentalsampling strategy was devised to detectsmall numbers ofSalmonellain such diverse environments as water troughs, feces, stall surfaces, and hay stacks, and (b) a previously publishedSalmonellaculture and isolation food sample protocol was adapted to detect Salmonellain theenvironmental samples.ii.) Using these two protocols, 893samples were procured and cultured for Salmonellaover a three-year period from the AU-CVM food animal (beef and dairy cattle) and equine environment. iii.) In 2015 and again in 2016, we cultured the feces of individual dairy cows in an attempt to locate the source of theSalmonella. iv.) In 2017and 2018, we performed 309 fecal cultures on the dairy calf herd. These calves were birthed by cows from the dairy herd, but the calf population is dynamic, as older calves were moved out as new calves weremoved into thegroup over the 21-month culture period. v.) In the summer of 2018 and again in May of 2019, we cultured 146 environmental samples from the Equine Reproduction Unit, a facility separate from the Equine Hospital which shares a fence line with the dairy calf herd. vi.) After isolating bothS.Muenster andS.Muenchen from both bovine and equine sites distant from each other on the AU-CVM campus, we naturally wondered if the strains from these different sites were the same strain or different (eachSalmonellaserotype is composed of multiple strains). We performed Pulse-Field Gel Electrophoresis (PFGE)on aset ofS.Muenchen strains from different sources, and we analyzed a set ofS.Muenster strains by whole genomic sequencing analysis. Data and Results: ii.) Much to our surprise, 39% (349) of the893 environmental samples containedSalmonella, and the contamination was widespread across the bovine and equine environments.Two serotypes ofSalmonellapredominated,S.Muenster andS.Cerro. We noted that the prevalence ofSalmonellawas highest in environments frequented by the dairy herd and decreased on a gradient scale the further the positive samples were from the dairy herd. Therefore, we cultured the feces of cows in the dairy herd. iii.) Ninety-one percent (20/22) of the dairy cows tested were positive for eitherS.Muenster orS.Cerro, or both. iv.) As expected, bothS.Muenster andS.Cerro were isolated from the dairy calves. Unexpectedly, a third Salmonellaserotype,S.Muenchen, emerged in the calves during this study, and eventually became the predominant serotype isolated from the calves bylate 2018. v.) As CVM administrators received our reports regardingSalmonellaisolation from multiple campus sites, the director of our Equine Reproduction Center (ERC) became worried and asked us to culture the ERC environment. During 5 weeks in May-June 2018, 131 ERC environmental samples were procured and cultured forSalmonella. Interestingly,S.Muenchen was isolated from each of these weekly ERC samples, along withS.Muenster andS.Cerro. TheS.Muenchen was present in the ERC and dairy calf samples simultaneously. The ERC was closed in September 2018, following these culture results. In May 2019, after7 months of no use, we cultured portions of the ERC to determine ifSalmonellawas still present in the environment. 11/15 environmental samples for this final sampling were positive forSalmonella, specifically,S.Muenster. vi.) TheS.Muenchen isolates from two calves and one isolate from the ERC were shown to be indistinguishable by PFGE analysis.Sequence analysis of 10S.Muenster strains isolated from the initial large-scale environmental survey, the dairy cows and dairy calves, the equine hospital and the Equine Reproduction Center were shown to be linked to a common ancestor. Impact: i.) Change in knowledge: Before we began this project, the food animal and equine sections were unaware of the extent ofSalmonellacontamination across their facilities. Previously, environmental sampling forSalmonellacontamination of these facilities employed insensitive methods.The culture method that we adapted to environmental testing proved to be extremely sensitive and unveiled contamination across large areas of the CVM campus. The sampling technique that we developed, and the repeated sampling that we performed over 3 years that generated 893 samples,showed us thatSalmonellamovement was occurring between the bovine and equine facilities on the vet school campus. ii.) Change in action: The results of our work made itglaringly obvious that biosecurity on the AU-CVM campus was basically non-existent. As a result of this project, the AU-CVM modified its approach to biosecurity: a) the equine clinicians immediately increased their biosecurity effortsboth in the Equine Teaching Hospital and the Equine Reproduction Center, including adding foot baths and changing the disinfectant being used. b) the Equine Reproduction Centerwas closed for many months to prevent further transmission ofSalmonellato both university and client-owned horses. The once passive surveillance forSalmonella, which focused on culturing only animals showing signs, changed to active surveillance, where all animals and the environment were cultured routinely. A biosecurity consultant was hired to map out a plan to decrease environmental contamination, and a full-time biosecurity officer was hired to lead infection control efforts in the college. Objective2: Use bacteriophages isolated from samples described in Objective 1 to naturally controlSalmonellain a contaminated environment. Major Activities Completed/Experiments Conducted: Forty-sevenSalmonella-positive samples from Objective 1 were screened for lytic bacteriophage activity against a set ofSalmonellaserotypes, including theS.Muenster andS.Cerro strains isolated from the CVM dairy herd. Individual bacteriophages targeting each of these serotypes were isolated from these samples, includingS.Muenster-targetedS73. This bacteriophage wasused to examine its ability to killS.Muenster on a concrete chip, concrete being a major surface used in both bovine and equine facilities. Data and Results: Sixteen of these 47 samples contained lytic activity againstS.Muenster, and 17 showed lytic activity againstS.Cerro. Surprisingly, 8 of these samples showed lytic activity againstbothS.Muenster andS.Cerro. This finding suggests that eitherthese samples contain (1) more than one lytic bacteriophage, or (2) a bacteriophage that lyses both serotypes. After isolating bacteriophage S73 (and others), we examined the number of viableS.Muenster present on the concrete chip following treatment with S73 for 10 min, 1 h, and 24 h, to determine if S73 could reduceSalmonellaon the chip. Remarkably, we saw an almost 100-fold decrease inS.Muenster CFU's on the concrete chip following a 1h exposure to S73. Impact: In the dairy parlor, where milk is drawn, disinfectants and cleaners are not used in order to prevent contamination of the milk. However, dairy parlors quickly become contaminated with bovine feces after a dairy herd has been milked. Our own work from Objective 1 showed that the AU-CVM dairy parlor was the mostSalmonella-contaminated facility in the entire study. This finding convinced us to isolateSalmonella-targeted bacteriophages to decrease this pathogen in this very contaminated environment. The finding that aSalmonella-targeted bacteriophage can killSalmonellaon concrete shows that this biological disinfection approach is feasible and worth future study.
Publications
- Type:
Theses/Dissertations
Status:
Published
Year Published:
2016
Citation:
Development Toward a Bovine Salmonella Model and a Bacteriophage Treatment Cocktail to Reduce Salmonella Peripheral Lymph Node Carriage in Calves. J. Forrest Shirley, MS Thesis. S. Price, Graduate Advisor. Auburn University, 2016.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2016
Citation:
Kitchens, S.R., Wright, J.C., Duran S.H., and Price, S.B. A Two Year Study of Environmental Salmonella Incidence and Proximal Contamination in a Multi-Species Animal Facility. Abstracts of This Is Research: Student Symposium 2016. Auburn, AL, April 13, 2016.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2018
Citation:
Environmental Sampling for Salmonella in an Equine Reproduction Center. Abstracts of Phi Zeta Research Emphasis Day, November, 2018
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2019
Citation:
"Movement of Salmonella in a Veterinary Teaching Hospital" Abstracts of the Auburn University Research Symposium, Spring, 2019.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2020
Citation:
Chick Embryo Lethality Assay for Salmonella Newport. Abstracts of Phi Zeta Research Emphasis Day, November, 2020
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Progress 10/01/18 to 09/30/19
Outputs
Target Audience:The target audiences for this reporting period included faculty and graduate students in the Department of Pathobiology, members of the College of Veterinary Medicine's (CVM) Infection Control Committee, and veterinary clinicians and staff of the CVM's Equine Section. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?Ph.D. graduate student Steven Kitchens performed the techniques utilized in Objectives 1 and 2 to generate the data described. Co-investigator Wright worked with Steven on designing statistical analyses designed to determine the significance of our data. Steven has since presented this data to a broad audience of students and faculty at the AU-CVM's annual Phi Zeta Research Emphasis Day. How have the results been disseminated to communities of interest?The results of ourSalmonella environmental sampling have been communicated to the new biosecurity officer, Andrea Perkins, of the CVM's Department of Clinical Sciences, along with individuals involved with safety issues at the CVM. Information about the location and extent ofSalmonella contamination across the CVM campus will help Andrea work with faculty, staff, and students to develop biosafety guidelines to prevent the dissemination ofSalmonella at the CVM. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
The Long-Term Goal of the project is to develop on-farm interventions to decrease transmission of Salmonella between food animal species. The Objectives of the project are to: (1) trace movement of Salmonella species amoung the Auburn University Collge of Veterinary Medicine's equine, beef, and dairy barns, along with associated pastures and natural water sources; (2) use bacteriophages isolated from samples described in Objective 1 to naturally control Salmonella in a contaminated environment. Salmonellosis in horses can result in a fulminant, often fatal, disease. Foals are especially susceptible, but adult mares and stallions also can develop systemic disease, although more commonly they shed the organism in their feces but show no signs of disease. In mixed animal species environments, such as those encountered on Alabama farms where food animals and horses are raised closely together, Salmonella species can be transmitted from cattle, poultry, or swine to horses. Because horses appear to develop disease signs more readily than food animal species infected with Salmonella, they can serve as sentinels for the presence of Salmonella in a mixed animal species environment. Therefore, horses can be utilized to determine the effectiveness of interventions put in place to prevent movement of Salmonella between animal species on farms. Objective1: Trace movement of Salmonella species among the Auburn University College of Veterinary Medicine's equine, beef, and dairy barns, along with associated pastures and natural water sources. In the previous project year, we reported on the isolation of three Salmonellaserotypes from the AU-CVM's Equine Reproduction Center (ERC),S.Cerro,S. Muenster, andS. Muenchen, all of which also had been isolated previously from dairy calves in the Food Animal Section of the AU-CVM. We speculated that these three serotypes were moving between cattle and horses within the veterinary school confines. To confirm this, in 2019 we compared S. Muenchen isolates from the food animal environment, dairy calves, and ERC environment using pulse-field electrophoresis (PFGE) analysis performed at the National Animal Disease Laboratory, Ames, IA. The PFGE results confirmed that the three S. Muenchen isolates were indistinguishable. In May, 2019, we returned to the ERC, 8 months following closure of the broodmare barn, to determine if Salmonella was still present in the environment. Ten samples were taken for Salmonella culture of the broodmare barn, three samples were taken from the stallion barn, and two samples from one of the adjoining pastures. Surprisingly, 11/15 samples were positive for Salmonella Muenster, including 7/10 of the broodmare barn samples, despite the fact that no horses had been in the broodmare barn for the preceding 8 months. These results indicate thatS. Muenster can survive in the environment for extended periods of time, and that environmental robustness differs among Salmonella serotypes, since serotypes Cerro and Muenchen had previously been isolated in the ERC environment alongside Muenster. Objective2: Use bacteriophages isolated from samples generated in Objective 1 to naturally controlSalmonella in a contaminated environment. In the previous reporting period, we isolated bacteriophages that targetedSalmonella serotypes Cerro and Muenster. In the current project period, we designed a simple experiment using one of our S. Muenster-targeted bacteriophages (S73) against its S. Muenster host on a concrete chip. We examined the number of viable Salmonella present on the chip following treatment with phage S73 for 10 min, 1 h, and 24 h, to determine if S73 could reduce S. Muenster on the chip. Remarkably, we saw an almost 100-fold decrease in S. Muenster CFU's on the concrete chip following a 1 h exposure to phage S73. Thus, surface decontamination ofSalmonella with lytic, targeted bacteriophages is feasible.
Publications
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2019
Citation:
"Movement of Salmonella in a Veterinary Teaching Hospital" Abstracts of the Auburn University Research Symposium, Spring, 2019.
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Progress 10/01/17 to 09/30/18
Outputs
Target Audience:The target audiences for this reporting period were the faculty veterinary clinicians, veterinary students, and staff employees of the College of Veterinary Medicine's Equine Reproduction Center (CVM-ERC). The results of the environmental Salmonellasampling performed by the Research Associate and undergraduate student were conveyed by the project PI weekly to the Director of the CVM-ERC and the Equine Section Leaderduring the Summer, 2018, sampling period. Changes/Problems:No changes in the approved project are anticipated for the next reporting period. What opportunities for training and professional development has the project provided?The ERC Salmonella sampling and initial bacteriophage isolation efforts described here composed the core of Mackenzie Michael's undergraduate research project and fulfilled her requirements in VBMS 4980 - Undergraduate Research. This graded course required Mackenzie to learn and carry out a set of research protocols, to analyze the results of her research, to write a paper describing her project, and to formally present her findings to a diverse audience. How have the results been disseminated to communities of interest?During the five-week ERC sampling period, the PI of the project sent weekly reports to the Director of the ERC, and to her supervisor, the Equine Section Head of the CVM Large Animal Teaching Hospital. These reports included the specific ERC facilities that turned up culture-positive for Salmonella. In response, during the fourth week of the sampling effort, the personnel at the ERC implemented a set of interventions to reduce the Salmonella contamination of their facility. Although the research team was not told what the interventions involved, comparison of the number of positive samples before and after the interventions were implementedshowed a significant drop in the Salmonella positive samples collected in Week 5. These results were communicated in a slide presentationto a CVM audience. The ERC continued its investigation by having horses housed at the ERC cultured for Salmonella. The culture results showed several adult animals to be Salmonella positive, and a university owned foal began showing signs of salmonellosis and was diagnosed with the disease. The Equine Section Head reported theSalmonella infection of ERC horses tothe CVM Infection Control Committee, which recommended that an outside consultant be hired to provide advice on how to manage the problem. The consultant's report resulted in the temporary closure of the ERC as the staff worked to implement interventions to remove Salmonella from the ERC environment and its horses. What do you plan to do during the next reporting period to accomplish the goals?We will continue working on Objective 2 by isolating and characterizing bacteriophages that target the endemic Salmonella in the CVM dairy herd and the ERC, including S. Muenster and S. Cerro. Once the most lytically active if these bacteriophages have been isolated, we will test their disinfecting activity on work surfaces, such as concrete used in animal stalls.
Impacts
What was accomplished under these goals?
Salmonellosis in horses can result in a fulminant, often fatal, disease. Foals are especially susceptible, but adult mares and stallions also can develop systemic disease, although more commonly they shed the organism in their feces but show no signs of disease. In mixed animal species environments, such as those encountered on Alabama farms where food animals and horses are raised proximally to each other, Salmonella can be transmitted from cattle, poultry, or swine to horses. Because horses appear to develop disease signs more readily than food animal species infected with Salmonella, they can serve as sentinelsfor the presence of Salmonella in a mixed animal species environment. Therefore, horses can be utilized to determine the effectiveness of interventions put in place to prevent movement of Salmonella between animal species onfarms. The Auburn University College of VeterinaryMedicine's (CVM) Equine Reproduction Center (ERC) shares a fence line with the CVM's dairy herd, individual dairy cows of which we previously showed to be shedding two serotypes of Salmonella, Muenster and Cerro. We reasoned that theproximal locationof theinfected cattle to the ERC may have resulted in movement of the pathogen into theERC's environment, and perhaps, into the horses themselves. We therefore undertooka thoroughsampling of the ERC environment for Salmonella. Objective 1: Trace proximal movement of Salmonella species among the Auburn University College of Veterinary Medicine's equine, beef, and dairy barns, along with associated pastures and natural water sources. Environmental samples from the ERC were taken over a period of 5 weeks in May/June, 2018. A sensitive, culture-based technique was used to isolate Salmonellafrom the samples. Five facilities within the ERC were sampled, composed of six different sample types - drains, feces, feed, floors, surfaces, and water. A total of 131 samples were taken, 49 (37%) of which were culture positive for Salmonella. The frequency of positive samples in ERC facilitieswas highest for the ERC road (100%) and the stallion barn (61%). The drains (67%), feces (55%), and standing water (61%) had the highest frequency of Salmonella isolation among sample types. Serotyping of the Salmonella isolates indicated serotypes Muenster, Cerro, and Muenchen were present in the ERC environment. These results confirmed our suspicion that Salmonella had moved proximally between the Equine Reproduction Center and the CVM Dairy, in one or both directions. Objective 2: Use bacteriophages isolated from samples described in Objective 1 to naturally control Salmonella in a contaminated environment.Forty-seven of the 131 Salmonella positive samples were screened for lytic bacteriophage activity against a set of Salmonella serotypes, including the two serotypes previously isolated from the CVM dairy herd, S. Cerro and S. Muenster. Seventeen of these 47 samples contained lytic activity against S. Cerro, and 16 showed lytic activity against S. Muenster. Surprisingly, 8 of these samples showed lytic activity against both S. Cerro and S. Muenster, suggesting either (1) the presence of more than one lytic bacteriophage, or (2)the presence of a bacteriophage that can lyse both serotypes.
Publications
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2018
Citation:
Environmental Sampling for Salmonella in an Equine Reproduction Center
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Progress 10/28/16 to 09/30/17
Outputs
Target Audience:The project target audience is food animal producers and the veterinarians who work with them. However, in this reporting period, the target audience was narrower. Because the environmental sampling was performed on food animal facilities within the AU-College of Veterinary Medicine, the PI of the project reported sampling results quarterly to the following CVM administrators: (1) the Teaching Hospital Director and the Hospital Administrator; (2) the Head of the Food Animal Section;(3) the Head of the Equine Section; (4) theveterinarian in charge of the CVM dairy herd, and(5) the Cooridinator of Animal Health & Disease Research. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?Both objectives of this project formed the core work of a Master's thesis project for graduate student Steven Kitchensin the PI's laboratory. Two undergraduate students, Austin Conley and Ryan Valentino, each enrolled in a Research Problems course with the PI and generated data for Objective 2 of the project. How have the results been disseminated to communities of interest?The project PI disseminated the quarterly Salmonella sampling results to section heads in the AU-CVM teaching hospital. Feedback from the Equine section head was frequent, and resulted in a change in the protocol used to disinfect the equine hospital barns. (Salmonella frequently cause serious disease in foals, and sometimes in adult horses, so preventing movement of the pathogen into the hospital barns is an ongoing priority.) Additionally, when one of the dairy cattle-associated Salmonella serotypes was isolated from mares in the AU-CVM's Equine Reproduction unit, these animals were no longer placed on pasture previously grazed by the dairy herd. The conclusion reached to instigate this change in grazing was that Salmonella shed by infected cattle into the pasture environment was infecting the mares. What do you plan to do during the next reporting period to accomplish the goals?No changes in the approved project are planned for the next reporting period. The focus of our efforts will be on completing Objective 2, specifically with testing our Salmonella Muenster and Cerro-targeted bacteriophages against these two serotypes on contaminated surfaces to model bacteriophage 'disinfection' of the dairy parlor. In addition, we will begin examining the dynamics of Salmonella shedding from naturally infected calves in the AU-CVM dairy herd.
Impacts
What was accomplished under these goals?
Foodborne bacterial diseases caused by Salmonella continue to be a major burden to human health. Most human cases of salmonellosis arise from contaminated food fromchickens,pigs, and cattle. In Alabama, where poultry production comprises a large agricultural commodity, many producers grow a second food animal (pigs or cattle) along with chickens. Because chickens are a major source of Salmonella, the potential for movement of the pathogen to other species of food animals is great. Therefore, defining the main parameters underscoring this movement is critical to establishing interventions to prevent on-farm transmission among food animals. The AU-CVMfood animalsection was chosen to examine proximal movement of Salmonella in a food animal setting because ofthe section'sproximity to other species of animals at the vet school, thus modeling the on-farm environment. A culture protocol originally designed to isolate Salmonella from food was modified to isolate Salmonella fromhay, feed, water troughs, gates, cattle feces, and pasture soil samples. Of the 631 environmental samples tested over a 2-year period, 36% were positive for Salmonella, indicating that the modified isolation protocol worked, and that the CVMfood animalenvironment is significantly contaminated with Salmonella. Importantly, Salmonella serotypeCerro, originally isolated froma bovine hospital barn, appeared to rapidly spread to multiple sites, includingtwo equine barns. These findings are important because they indicate thatthis very sensitiveSalmonella cultureapproach should detect proximal Salmonella movementon Alabama farms where two or more species of food animals are produced. Objective 1: Trace proximal movement of Salmonella species among the AU-CVM equine, beef, and dairy barns, along with associated pastures and natural water sources. Quarterly sampling of the AU-CVM facilities over two years resulted in the culture of631 samples for Salmonella. Thirty-six percent of these samples were positive, regardless of animal species exposure. Variables associatd with the increased probability for isolation of Salmonella from environmental samples included the summer season, water and drain samples, samples exposed to bovine resident animals, indoor environments such as buildings, and the dairy and beef barn locations. A significantly increased frequency of Salmonella isolation from environmental samples exposed to dairy cattle indicated that cattle are either the source of this pathogen, or are serving as the amplifying host for Salmonella. The consistent recovery of two cattle-associated Salmonella serotypes, serotypes Muenster and Cerro, supports this conclusion. Objectve 2: Use bacteriophages isolated from samples described inObjective 1 to naturally control Salmonella in a contaminated environment. Lytic bacteriophages are naturally occurringviruses that infect and multiply inside bacteria, eventually lysing the host bacterium with release of new virions. Because bacteriophages are most easily found with their bacterial host, we examined a subset of the 230 Salmonella-positive samples generated in Objective 1for Salmonella-targeted phages. We found phages targeted to both serotype Muenster, and serotype Cerro, in these samples. The next step will be to test the ability of these phages to 'disinfect' surfaces similar to the ones found in a dairy parlor, where normal chemical disinfectants are not used to prevent chemical contamination of the milk.
Publications
- Type:
Theses/Dissertations
Status:
Published
Year Published:
2016
Citation:
Development Toward a Bovine Salmonella Model and a Bacteriophage Treatment Cocktail to Reduce Salmonella Peripheral Lymph Node Carriage in Calves. J. Forrest Shirley, MS Thesis. S. Price, Graduate Advisor. Auburn University, 2016.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2016
Citation:
Kitchens, S.R., Wright, J.C., Duran S.H., and Price, S.B. A Two Year Study of Environmental Salmonella Incidence and Proximal Contamination in a Multi-Species Animal Facility. This Is Research: Student Symposium 2016. Auburn, AL, April 13, 2016.
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