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Johanna Elfenbein, DVM, PhD, DACVIM

Assistant Professor, Equine Medicine


Dr. Elfenbein received her undergraduate degree in biochemical sciences from Harvard in 2003. She earned her DVM from the University of Florida College of Veterinary Medicine in 2007. She completed an internship in large animal medicine and surgery at the University of Georgia and returned to the University of Florida for her large animal internal medicine residency. She attained board certification in the American College of Veterinary Internal Medicine in 2011. Following residency training, Dr. Elfenbein went to Texas A&M University for her PhD training in biomedical sciences, funded by the NIH T32 fellowship. She completed her PhD in 2014 studying Salmonella pathogenesis and began employment at NCSU CVM in 2014. She received the AVMA-AVMF Young Investigator Award (2015) and the University of Florida Young Alumni Award (2015) recognizing her research contributions. Her research is currently funded by the National Institutes of Health.
Diplomate, American College of Veterinary Internal Medicine (Large Animal)
Member American Society for Microbiology
Member American Veterinary Medical Association
PhD (2014, Texas A&M University)
Diplomate, ACVIM (2011)
DVM (2007, University of Florida)
Gastroenterology, Infectious Diseases
Salmonella Pathogenesis:
Salmonella is the leading cause of bacterial foodborne gastroenteritis in people in the United States. This bacterium is capable of colonizing and causing disease in all species of mammals and birds. Animals that appear normal may harbor this pathogen in the intestine and may serve as sources of this bacterium to infect other animals and people. This is of particular concern in food-producing animals, as these animals are a direct conduit to contamination of the human food chain. My laboratory studies the properties of the bacterium that are needed for it to grow and cause disease in the mammalian intestine. My overall goal is to develop new antibiotics to specifically target this pathogen and new vaccines to prevent Salmonella colonization in large animals. This work is funded by the National Institutes of Health (National Institute of Allergy and Infectious Disease) and by North Carolina State University.

Equine Colic:
Colic is a leading cause of morbidity and mortality in horses. Colic can be caused by numerous factors including inadequate water intake, feeding practices, infectious diseases, and intestinal accidents. Work in my laboratory is searching for new infectious causes of colic with the overall goal to improve diagnosis and prevention of colic.

  • (2017) Identifying novel innate immune response targets to alter Salmonella Typhimurium pathogenesis.Cruz E, Westerman T, Elfenbein J, Sheats MK. | Poster, Summer Undergraduate Research Symposium, Office of Undergraduate Research, NCSU, Raleigh, NC.
  • (2017) Identification of Salmonella Typhimurium genes essential to induce the neutrophil oxidative burst.Westerman TL, Sheats MK, Jones SL, Elfenbein JR. | Poster, Mid-Atlantic Microbial Pathogenesis Meeting
  • (2016) Development of a neutrophil-Salmonella co-culture system to study Salmonella genes that alter the neutrophil respiratory burst.Westerman TL, Sheats MK, Jones SL, Elfenbein JR. | Oral Presentation, Duke Innate Immunity Group Symposium
  • (2016) A high-throughput in vitro system to study Salmonella-neutrophil interactions.Westerman TL, Sheats MK, Jones SL, Elfenbein JR. | Poster, 5th ASM Conference on Salmonella
  • (2016) Novel two-step hierarchical screening of mutant pools reveals mutants under selection in chicks.Yang H-J, Bogomolnaya LM, Elfenbein JR, Endicott-Yazdani T, Reynolds MM, Porwollik S, Cheng P, Xia X-Q, McClelland M, Andrews-Polymenis HL | Infection and Immunity 2016 Mar 24;84(4):1226-38.
  • (2015) Multicopy Single-Stranded DNA Directs Intestinal Colonization of Enteric Pathogens.Elfenbein JR, Knodler LA, Nakayasu ES, Ansong C, Brewer HM, Bogomolnaya L, Adams LG, McClelland M, Adkins JN, Andrews-Polymenis HL | PLoS Genet 2015 Sep;11(9):e1005472. PubMed PMID: 26367458.
  • (2014) Systemic and anti-nociceptive effects of prolonged lidocaine, ketamine, and butorphanol infusions alone and in combination in healthy horses.Elfenbein JR, Robertson SA, MacKay RJ, KuKanich B, Sanchez LC. | BMC Veterinary Research. 10(Suppl 1):S6. doi:10.1186/1746-6148-10-S1-S6. 2014
  • (2013) Novel determinants of intestinal colonization of Salmonella enterica serotype Typhimurium identified in bovine enteric infection.Elfenbein JR, Endicott-Yazdani T, Porwollik S, Bogomolnaya LM, Cheng P, Guo J, Zheng Y, Yang H, Talamantes M, Shields C, Maple A, Ragoza Y, DeAtley K, Tatsch T, Cui P, Andrews KD, McClelland M, Lawhon SD, Andrews-Polymenis H. | Infection and Immunity. doi:10.1128/IAI.00874-13. 2013.
  • (2012) Effect of butorphanol on thermal nociceptive threshold in healthy pony foals.McGowan KT, Elfenbein JR, Robertson SA, Sanchez LC. | Equine Veterinary Journal. doi: 10.1111/j.2042-3306.2012.00673.x. 2012.
  • (2012) Prevalence of gastric and duodenal ulceration in 691 non-surviving foals (1995-2006).Elfenbein JR, Sanchez LC. | Equine Veterinary Journal. 44(s41)76-9. 2012.
  • (2011) Systemic effects of a prolonged continuous infusion of ketamine in healthy horses.Elfenbein JR, Robertson SA, Corser AA, Urion RJ, Sanchez LC. | Journal of Veterinary Internal Medicine. 25(5) 1134-7. 2011.
  • (2011) Pathology in practice. Severe, chronic, segmental proliferative and ulcerative enteritis with intraepithelial curved bacilli (L. intracellularis) and multifocal transmural necrosis.Ellis AE, Hart KA, Elfenbein JR. | Journal of the American Veterinary Medical Association. 238(11)1417-9. 2011.
  • (2010) Effects of deferoxamine on iron elimination following blood transfusion in neonatal foals.Elfenbein JR, Giguère S, Meyer SK, Javsicas LH, Zimmel DN, Farina LL, Sanchez LC. | Journal of Veterinary Internal Medicine. 24(6) 1475-82. 2010.
  • (2009) Pathology in Practice: Interstitial pneumonia with fibrosis and intranuclear inclusion bodies.Kubiski SV, Rech RR, Camus MS, Pellegrini-Masini A, Elfenbein JR, Howerth EW. | Journal of the American Veterinary Medical Association. 235(4)381-3. 2009.
  • (2009) Effect of detomidine on somatic and visceral nociception and duodenal motility in conscious horses.Elfenbein J, Sanchez LC, Robertson S, Cole C, Sams R. | Veterinary Anaesthesia and Analgesia. 36(2)162-72. 2009.
  • (2008) Hypoglycemia and hyperlactatemia associated with lymphoma in an Angus cow.Elfenbein J, Credille B, Camus M, LeRoy B, Blas-Machado U, Woolums A. | Journal of Veterinary Internal Medicine. 22(6)1441-3. 2008.
  • (2008) Effect of acepromazine, butorphanol, or N-butylscopolammonium bromide on somatic and visceral nociception and duodenal motility in conscious horses.Sanchez LC, Elfenbein JR, Robertson SA. | American Journal of Veterinary Research. 69(5)579-585. 2008.