{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T12:19:36Z","timestamp":1791289176215,"version":"4.3.0"},"reference-count":74,"publisher":"American Veterinary Medical Association (AVMA)","issue":"2","license":[{"start":{"date-parts":[[2026,2,1]],"date-time":"2026-02-01T00:00:00Z","timestamp":1769904000000},"content-version":"unspecified","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["javma"],"published-print":{"date-parts":[[2026,2,1]]},"abstract":"Abstract<\/jats:title>\n \n Objective<\/jats:title>\n To describe common bacterial isolates cultured from sick neonatal foals and their antimicrobial susceptibility and resistance patterns.<\/jats:p>\n <\/jats:sec>\n \n Methods<\/jats:title>\n Medical records of foals \u2264 30 days of age, admitted to the Ontario Veterinary College from 2020 to 2023, and with a positive aerobic bacterial culture and susceptibility testing performed (Kirby-Bauer method) were included. A descriptive analysis of species isolated and antimicrobial and multidrug resistance profiles was performed.<\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n \n 62 samples from 60 predominantly Thoroughbred (42% [25 of 60]) neonatal foals (median age, 8 days) yielded 104 isolates of 34 bacterial species and genera.\n Enterococcus<\/jats:italic>\n spp (22% [23 of 104]),\n Streptococcus equi<\/jats:italic>\n subsp\n zooepidemicus<\/jats:italic>\n (17% [18 of 104]),\n Escherichia coli<\/jats:italic>\n (12% [12 of 104]),\n Actinobacillus equuli<\/jats:italic>\n subsp\n haemolyticus<\/jats:italic>\n (8% [8 of 104]), and\n Staphylococcus aureus<\/jats:italic>\n (8% [8 of 104]) were most frequent. Antimicrobial susceptibility was highest to chloramphenicol (74% [75 of 102]), ceftiofur (68% [71 of 104]), and enrofloxacin (64% [66 of 103]). Gram-positive isolates were most susceptible to chloramphenicol (87% [53 of 61]), ampicillin (75% [38 of 61]), and rifampin (70% [43 of 61]). Gram-negative bacteria were most susceptible to enrofloxacin (81% [34 of 42]) and ceftiofur (71% [30 of 42]). An amikacin plus ampicillin combination had the highest susceptibility (78% [70 of 90]). Multidrug resistance for the 104 isolates was 78% (81 of 104): 66% (41 of 62) for gram-positive isolates and 93% (39 of 42) for gram-negative isolates.\n <\/jats:p>\n <\/jats:sec>\n \n Conclusions<\/jats:title>\n \n S equi<\/jats:italic>\n subsp\n zooepidemicus<\/jats:italic>\n was the most common species and Enterococcus was the most common genus, but a breadth of equine-associated and environmental species were cultured. There was a high proportion of isolates expressing multidrug resistance and low susceptibility to first-line antimicrobials.\n <\/jats:p>\n <\/jats:sec>\n \n Clinical Relevance<\/jats:title>\n Ongoing susceptibility monitoring and implementation of an effective antimicrobial stewardship program for this patient population is required.<\/jats:p>\n <\/jats:sec>","DOI":"10.2460\/javma.25.05.0339","type":"journal-article","created":{"date-parts":[[2025,10,1]],"date-time":"2025-10-01T17:38:52Z","timestamp":1759340332000},"page":"1-8","source":"Crossref","is-referenced-by-count":2,"title":["A high proportion of bacterial isolates from septic neonatal foals in Ontario express multidrug resistance and low susceptibility to first-line antimicrobials"],"prefix":"10.2460","volume":"264","author":[{"given":"Daniela","family":"Espinosa Seoane","sequence":"first","affiliation":[{"name":"Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christopher Bruce","family":"Riley","sequence":"additional","affiliation":[{"name":"Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniel G.","family":"Kenney","sequence":"additional","affiliation":[{"name":"Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ashley","family":"Spencer","sequence":"additional","affiliation":[{"name":"Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luis Guillermo","family":"Arroyo","sequence":"additional","affiliation":[{"name":"Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1272","reference":[{"issue":"10","key":"ref1","series-title":"J Am Vet Med Assoc","first-page":"1608","article-title":"Bacterial isolates from blood and their susceptibility patterns in critically ill foals: 543 cases (1991-1998)","volume":"218","author":"Marsh PS","year":"2001","unstructured":"Marsh PS, Palmer JE. Bacterial isolates from blood and their susceptibility patterns in critically ill foals: 543 cases (1991-1998). J Am Vet Med Assoc. 2001;218(10):1608-1610. doi:10.2460\/javma.2001.218.1608"},{"issue":"7","key":"ref2","series-title":"Aust Vet J","first-page":"266","article-title":"Blood culture isolates and antimicrobial sensitivities from 427 critically ill neonatal foals","volume":"86","author":"Russell CM","year":"2008","unstructured":"Russell CM, Axon JE, Blishen A, Begg AP. Blood culture isolates and antimicrobial sensitivities from 427 critically ill neonatal foals. Aust Vet J. 2008;86(7):266-271. doi:10.1111\/j.1751-0813.2008.00311.x"},{"issue":"9","key":"ref3","series-title":"J Am Vet Med Assoc","first-page":"1446","article-title":"Factors associated with survival of neonatal foals with bacteremia and racing performance of surviving Thoroughbreds: 423 cases (1982-2007)","volume":"233","author":"Sanchez LC","year":"2008","unstructured":"Sanchez LC, Gigu\u00e8re S, Lester GD. Factors associated with survival of neonatal foals with bacteremia and racing performance of surviving Thoroughbreds: 423 cases (1982-2007). J Am Vet Med Assoc. 2008;233(9):1446-1452. doi:10.2460\/javma.233.9.1446"},{"issue":"4","key":"ref4","series-title":"Aust Vet J","first-page":"163","article-title":"Blood culture isolates and antimicrobial sensitivities from 1621 critically ill neonatal foals (2005-2022)","volume":"103","author":"Flood JA","year":"2025","unstructured":"Flood JA, Collins NM, Russell CM, Cuming RS, Carrick JB, Cudmore LA. Blood culture isolates and antimicrobial sensitivities from 1621 critically ill neonatal foals (2005-2022). Aust Vet J. 2025;103(4):163-170. doi:10.1111\/avj.13423"},{"issue":"4","key":"ref5","series-title":"Equine Vet J","first-page":"607","article-title":"Prognosis for survival to discharge and racing performance in Thoroughbred foals treated for single joint septic arthritis (2009-2016)","volume":"55","author":"Whisenant KD","year":"2023","unstructured":"Whisenant KD, Ruggles AJ, Stefanovski D, Woodie JB, Hopper SA, Embertson RM. Prognosis for survival to discharge and racing performance in Thoroughbred foals treated for single joint septic arthritis (2009-2016). Equine Vet J. 2023;55(4):607-617. doi:10.1111\/evj.13892"},{"issue":"1","key":"ref6","series-title":"Equine Vet J","first-page":"84","article-title":"Bacteraemia in neonatal foals: clinicopathological differences between gram-positive and gram-negative infections, and single organism and mixed infections","volume":"39","author":"Corley KTT","year":"2007","unstructured":"Corley KTT, Pearce G, Magdesian KG, Wilson WD. Bacteraemia in neonatal foals: clinicopathological differences between gram-positive and gram-negative infections, and single organism and mixed infections. Equine Vet J. 2007;39(1):84-89. doi:10.2746\/042516407X157585"},{"issue":"5","key":"ref7","series-title":"J Vet Intern Med","first-page":"1203","article-title":"Bacteremia in equine neonatal diarrhea: a retrospective study (1990-2007)","volume":"22","author":"Hollis AR","year":"2008","unstructured":"Hollis AR, Wilkins PA, Palmer JE, Boston RC. Bacteremia in equine neonatal diarrhea: a retrospective study (1990-2007). J Vet Intern Med. 2008;22(5):1203-1209. doi:10.1111\/j.1939-1676.2008.0152.x"},{"issue":"2","key":"ref8","series-title":"J Vet Intern Med","first-page":"e70004","article-title":"The systemic inflammatory response syndrome and predictors of infection and mortality in 1068 critically ill newborn foals","volume":"39","author":"Wilkins PA","year":"2025","unstructured":"Wilkins PA, Wong D, Slovis NM, The systemic inflammatory response syndrome and predictors of infection and mortality in 1068 critically ill newborn foals. J Vet Intern Med. 2025;39(2):e70004. doi:10.1111\/jvim.70004"},{"issue":"5","key":"ref9","series-title":"J Vet Emerg Crit Care (San Antonio)","first-page":"660","article-title":"Retrospective evaluation of blood culture isolates and sepsis survival rate in foals in the Czech Republic: 50 cases (2011-2013)","volume":"25","author":"Hytychov\u00e1 T","year":"2015","unstructured":"Hytychov\u00e1 T, Bezd\u011bkov\u00e1 B. Retrospective evaluation of blood culture isolates and sepsis survival rate in foals in the Czech Republic: 50 cases (2011-2013). J Vet Emerg Crit Care (San Antonio). 2015;25(5):660-666. doi:10.1111\/vec.12348"},{"issue":"2","key":"ref10","series-title":"N Z Vet J","first-page":"107","article-title":"Antimicrobial susceptibility of bacteria isolated from neonatal foal samples submitted to a New Zealand veterinary pathology laboratory (2004 to 2013)","volume":"64","author":"Toombs-Ruane LJ","year":"2016","unstructured":"Toombs-Ruane LJ, Riley CB, Kendall AT, Hill KE, Benschop J, Rosanowski SM. Antimicrobial susceptibility of bacteria isolated from neonatal foal samples submitted to a New Zealand veterinary pathology laboratory (2004 to 2013). N Z Vet J. 2016;64(2):107-111. doi:10.1080\/00480169.2015.1109006"},{"issue":"3","key":"ref11","series-title":"J Vet Intern Med","first-page":"1193","article-title":"Antibiograms of field and hospital acquired equine neonatal bacterial fluid cultures in the Midwestern United States: 149 samples (2007-2018)","volume":"37","author":"Bookbinder LC","year":"2023","unstructured":"Bookbinder LC, Mani R, Carr EA. Antibiograms of field and hospital acquired equine neonatal bacterial fluid cultures in the Midwestern United States: 149 samples (2007-2018). J Vet Intern Med. 2023;37(3):1193-1200. doi:10.1111\/jvim.16671"},{"issue":"6","key":"ref12","series-title":"Crit Care Med","first-page":"1589","article-title":"Duration of hypotension before initiation of effective antimicrobial therapy is the critical determinant of survival in human septic shock","volume":"34","author":"Kumar A","year":"2006","unstructured":"Kumar A, Roberts D, Wood KE, Duration of hypotension before initiation of effective antimicrobial therapy is the critical determinant of survival in human septic shock. Crit Care Med. 2006;34(6):1589-1596. doi:10.1097\/01.CCM.0000217961.75225.E9"},{"key":"ref13","series-title":"Vet J","first-page":"74","article-title":"Initial antimicrobial treatment of foals with sepsis: do our choices make a difference?","volume":"243","author":"Theelen MJP","year":"2019","unstructured":"Theelen MJP, Wilson WD, Byrne BA, Edman JM, Kass PH, Magdesian KG. Initial antimicrobial treatment of foals with sepsis: do our choices make a difference? Vet J. 2019;243:74-76. doi:10.1016\/j.tvjl.2018.11.012"},{"issue":"2","key":"ref14","series-title":"J Vet Intern Med","first-page":"955","article-title":"Differences in isolation rate and antimicrobial susceptibility of bacteria isolated from foals with sepsis at admission and after \u226548 hours of hospitalization","volume":"34","author":"Theelen MJP","year":"2020","unstructured":"Theelen MJP, Wilson WD, Byrne BA, Differences in isolation rate and antimicrobial susceptibility of bacteria isolated from foals with sepsis at admission and after \u226548 hours of hospitalization. J Vet Intern Med. 2020;34(2):955-963. doi:10.1111\/jvim.15692"},{"issue":"2","key":"ref15","series-title":"Equine Vet J","first-page":"161","article-title":"Temporal trends in in vitro antimicrobial susceptibility patterns of bacteria isolated from foals with sepsis: 1979-2010","volume":"46","author":"Theelen MJP","year":"2014","unstructured":"Theelen MJP, Wilson WD, Edman JM, Magdesian KG, Kass PH. Temporal trends in in vitro antimicrobial susceptibility patterns of bacteria isolated from foals with sepsis: 1979-2010. Equine Vet J. 2014;46(2):161-168. doi:10.1111\/evj.12130"},{"issue":"11","key":"ref16","series-title":"Schweiz Arch Tierheilkd","first-page":"665","article-title":"Antimicrobial susceptibility patterns of blood culture isolates from foals in Switzerland","volume":"160","author":"Fouch\u00e9 N","year":"2018","unstructured":"Fouch\u00e9 N, Gerber V, Thomann A, Perreten V. Antimicrobial susceptibility patterns of blood culture isolates from foals in Switzerland. Schweiz Arch Tierheilkd. 2018;160(11):665-671. doi:10.17236\/sat00184"},{"issue":"9","key":"ref17","series-title":"Can Vet J","first-page":"951","article-title":"Antimicrobial resistance in bacteria isolated from horses from the Atlantic provinces, Canada (1994 to 2013)","volume":"59","author":"Awosile BB","year":"2018","unstructured":"Awosile BB, Heider LC, Saab ME, McClure JT. Antimicrobial resistance in bacteria isolated from horses from the Atlantic provinces, Canada (1994 to 2013). Can Vet J. 2018;59(9):951-957."},{"issue":"5","key":"ref18","series-title":"Can Vet J","first-page":"292","article-title":"Aerobic bacterial isolates in horses in a university hospital, 1986-1988","volume":"32","author":"Lavoie JP","year":"1991","unstructured":"Lavoie JP, Couture L, Higgins R, Laverty S. Aerobic bacterial isolates in horses in a university hospital, 1986-1988. Can Vet J. 1991;32(5):292-294."},{"issue":"7","key":"ref19","series-title":"Can Vet J","first-page":"747","article-title":"Evolution of in vitro antimicrobial resistance in an equine hospital over 3 decades","volume":"57","author":"Malo A","year":"2016","unstructured":"Malo A, Cluzel C, Labrecque O, Beauchamp G, Lavoie JP, Leclere M. Evolution of in vitro antimicrobial resistance in an equine hospital over 3 decades. Can Vet J. 2016;57(7):747-751."},{"issue":"2","key":"ref20","series-title":"Can Vet J","first-page":"153","article-title":"Bacterial isolates from equine infections in western Canada (1998-2003)","volume":"49","author":"Clark C","year":"2008","unstructured":"Clark C, Greenwood S, Boison JO, Chirino-Trejo M, Dowling PM. Bacterial isolates from equine infections in western Canada (1998-2003). Can Vet J. 2008;49(2):153-160."},{"issue":"1","key":"ref21","series-title":"BMC Vet Res","first-page":"479","article-title":"Extended spectrum \u03b2 lactamase-producing Enterobacteriaceae shedding by race horses in Ontario, Canada","volume":"16","author":"Shnaiderman-Torban A","year":"2020","unstructured":"Shnaiderman-Torban A, Navon-Venezia S, Paitan Y, Extended spectrum \u03b2 lactamase-producing Enterobacteriaceae shedding by race horses in Ontario, Canada. BMC Vet Res. 2020;16(1):479. doi:10.1186\/s12917-020-02701-z"},{"issue":"3","key":"ref22","series-title":"J Vet Intern Med","first-page":"1185","article-title":"Evaluation of updated sepsis scoring systems and systemic inflammatory response syndrome criteria and their association with sepsis in equine neonates","volume":"32","author":"Wong DM","year":"2018","unstructured":"Wong DM, Ruby RE, Dembek KA, Evaluation of updated sepsis scoring systems and systemic inflammatory response syndrome criteria and their association with sepsis in equine neonates. J Vet Intern Med. 2018;32(3):1185-1193. doi:10.1111\/jvim.15087"},{"issue":"3","key":"ref23","series-title":"Equine Vet J","first-page":"536","article-title":"Dorothy Russell Havemayer Working Group on Foal Sepsis. Report from the 2024 Dorothy Russell Havemeyer Working Group Meeting on consensus definitions for foal sepsis","volume":"57","author":"Wilkins PA","year":"2025","unstructured":"Wilkins PA, Wong DM; Dorothy Russell Havemayer Working Group on Foal Sepsis. Report from the 2024 Dorothy Russell Havemeyer Working Group Meeting on consensus definitions for foal sepsis. Equine Vet J. 2025;57(3):536-539. doi:10.1111\/evj.14443"},{"key":"ref24","article-title":"Performance Standards for Antimicrobial Disk and Dilution Susceptibility Tests for Bacteria Isolated From Animals","author":"Lubbers BV","year":"2018","unstructured":"Lubbers BV, Papich MG, Schwarz S, Performance Standards for Antimicrobial Disk and Dilution Susceptibility Tests for Bacteria Isolated From Animals. 4th ed. Clinical and Laboratory Standards Institute; 2018."},{"issue":"3","key":"ref25","series-title":"Clin Microbiol Infect","first-page":"268","article-title":"Multidrug-resistant, extensively drug-resistant and pandrug-resistant bacteria: an international expert proposal for interim standard definitions for acquired resistance","volume":"18","author":"Magiorakos AP","year":"2012","unstructured":"Magiorakos AP, Srinivasan A, Carey RB, Multidrug-resistant, extensively drug-resistant and pandrug-resistant bacteria: an international expert proposal for interim standard definitions for acquired resistance. Clin Microbiol Infect. 2012;18(3):268-281. doi:10.1111\/j.1469-0691.2011.03570.x"},{"key":"ref26","article-title":"Modern Applied Statistics with S","author":"Venables WN","year":"2002","unstructured":"Venables WN, Ripley BD. Modern Applied Statistics with S. 4th ed. Springer; 2002. doi:10.1007\/978-0-387-21706-2"},{"key":"ref27","article-title":"R version 4.4.1","year":"2024","unstructured":"R: A Language and Environment for Statistical Computing. R version 4.4.1, R Core Team; 2024. Accessed October 30, 2024. https:\/\/cran.r-project.org\/manuals.html"},{"key":"ref28","series-title":"Equine Infectious Diseases","first-page":"265","article-title":"Streptococcal infections","author":"Waller AS","year":"2014","unstructured":"Waller AS, Sellon DC, Sweeney CR, Streptococcal infections. In: Equine Infectious Diseases. Elsevier; 2014:265\u2013277. doi:10.1016\/B978-1-4557-0891-8.00028-2"},{"issue":"22","key":"ref29","series-title":"Vet Rec","first-page":"543","article-title":"Umbilical infections in foals: microbiological investigation and management","volume":"180","author":"Rampacci E","year":"2017","unstructured":"Rampacci E, Passamonti F, Bottinelli M, Umbilical infections in foals: microbiological investigation and management. Vet Rec. 2017;180(22):543. doi:10.1136\/vr.103999"},{"key":"ref30","series-title":"PeerJ","first-page":"e13682","article-title":"Antimicrobial resistance among Streptococcus equi subspecies zooepidemicus and Rhodococcus equi isolated from equine specimens submitted to a diagnostic laboratory in Kentucky, USA","volume":"10","author":"Lord J","year":"2022","unstructured":"Lord J, Carter C, Smith J, Locke S, Phillips E, Odoi A. Antimicrobial resistance among Streptococcus equi subspecies zooepidemicus and Rhodococcus equi isolated from equine specimens submitted to a diagnostic laboratory in Kentucky, USA. PeerJ. 2022;10:e13682. doi:10.7717\/peerj.13682"},{"key":"ref31","series-title":"Prev Vet Med","first-page":"105857","article-title":"Antimicrobial susceptibility of Salmonella and Escherichia coli from equids sampled in the NAHMS 2015-16 equine study and association of management factors with resistance","volume":"213","author":"Kohnen AB","year":"2023","unstructured":"Kohnen AB, Wiedenheft AM, Traub-Dargatz JL, Antimicrobial susceptibility of Salmonella and Escherichia coli from equids sampled in the NAHMS 2015-16 equine study and association of management factors with resistance. Prev Vet Med. 2023;213:105857. doi:10.1016\/j.prevetmed.2023.105857"},{"key":"ref32","series-title":"Vet J","first-page":"42","article-title":"Enterococcus infections in foals","volume":"248","author":"Willis AT","year":"2019","unstructured":"Willis AT, Magdesian KG, Byrne BA, Edman JM. Enterococcus infections in foals. Vet J. 2019;248:42-47. doi:10.1016\/j.tvjl.2019.04.005"},{"issue":"6","key":"ref33","series-title":"Equine Vet Educ","first-page":"328","article-title":"Antimicrobial therapy for multidrug resistant pathogens","volume":"21","author":"Weese JS","year":"2009","unstructured":"Weese JS. Antimicrobial therapy for multidrug resistant pathogens. Equine Vet Educ. 2009;21(6):328-334. doi:10.2746\/095777308X334293"},{"issue":"1","key":"ref34","series-title":"Antimicrob Resist Infect Control","first-page":"130","article-title":"Enterococcus faecium: from microbiological insights to practical recommendations for infection control and diagnostics","volume":"9","author":"Zhou X","year":"2020","unstructured":"Zhou X, Willems RJL, Friedrich AW, Rossen JWA, Bathoorn E. Enterococcus faecium: from microbiological insights to practical recommendations for infection control and diagnostics. Antimicrob Resist Infect Control. 2020;9(1):130. doi:10.1186\/s13756-020-00770-1"},{"issue":"12","key":"ref35","series-title":"J Equine Vet Sci","first-page":"1057","article-title":"Genomic description of antibiotic resistance in Escherichia coli and Enterococci isolates from healthy Lusitano horses","volume":"33","author":"Moura I","year":"2013","unstructured":"Moura I, Torres C, Silva N, Somalo S, Igrejas G, Poeta P. Genomic description of antibiotic resistance in Escherichia coli and Enterococci isolates from healthy Lusitano horses. J Equine Vet Sci. 2013;33(12):1057-1063. doi:10.1016\/j.jevs.2013.04.002"},{"key":"ref36","series-title":"J Clin Microbiol","first-page":"e02210","article-title":"What\u2019s new in antibiograms? Updating CLSI M39 guidance with current trends","volume":"60","author":"Simner PJ","year":"2022","unstructured":"Simner PJ, Hindler JA, Bhowmick T, What\u2019s new in antibiograms? Updating CLSI M39 guidance with current trends. J Clin Microbiol. 2022;60:e02210-21. doi:10.1128\/jcm.02210-21"},{"issue":"2","key":"ref37","series-title":"J Vet Intern Med","first-page":"487","article-title":"ACVIM consensus statement on therapeutic antimicrobial use in animals and antimicrobial resistance","volume":"29","author":"Weese JS","year":"2015","unstructured":"Weese JS, Gigu\u00e8re S, Guardabassi L, ACVIM consensus statement on therapeutic antimicrobial use in animals and antimicrobial resistance. J Vet Intern Med. 2015;29(2):487-498. doi:10.1111\/jvim.12562"},{"issue":"10","key":"ref1","series-title":"J Am Vet Med Assoc","first-page":"1608","article-title":"Bacterial isolates from blood and their susceptibility patterns in critically ill foals: 543 cases (1991-1998)","volume":"218","author":"Marsh PS","year":"2001","unstructured":"Marsh PS, Palmer JE. Bacterial isolates from blood and their susceptibility patterns in critically ill foals: 543 cases (1991-1998). J Am Vet Med Assoc. 2001;218(10):1608-1610. doi:10.2460\/javma.2001.218.1608"},{"issue":"7","key":"ref2","series-title":"Aust Vet J","first-page":"266","article-title":"Blood culture isolates and antimicrobial sensitivities from 427 critically ill neonatal foals","volume":"86","author":"Russell CM","year":"2008","unstructured":"Russell CM, Axon JE, Blishen A, Begg AP. Blood culture isolates and antimicrobial sensitivities from 427 critically ill neonatal foals. Aust Vet J. 2008;86(7):266-271. doi:10.1111\/j.1751-0813.2008.00311.x"},{"issue":"9","key":"ref3","series-title":"J Am Vet Med Assoc","first-page":"1446","article-title":"Factors associated with survival of neonatal foals with bacteremia and racing performance of surviving Thoroughbreds: 423 cases (1982-2007)","volume":"233","author":"Sanchez LC","year":"2008","unstructured":"Sanchez LC, Gigu\u00e8re S, Lester GD. Factors associated with survival of neonatal foals with bacteremia and racing performance of surviving Thoroughbreds: 423 cases (1982-2007). J Am Vet Med Assoc. 2008;233(9):1446-1452. doi:10.2460\/javma.233.9.1446"},{"issue":"4","key":"ref4","series-title":"Aust Vet J","first-page":"163","article-title":"Blood culture isolates and antimicrobial sensitivities from 1621 critically ill neonatal foals (2005-2022)","volume":"103","author":"Flood JA","year":"2025","unstructured":"Flood JA, Collins NM, Russell CM, Cuming RS, Carrick JB, Cudmore LA. Blood culture isolates and antimicrobial sensitivities from 1621 critically ill neonatal foals (2005-2022). Aust Vet J. 2025;103(4):163-170. doi:10.1111\/avj.13423"},{"issue":"4","key":"ref5","series-title":"Equine Vet J","first-page":"607","article-title":"Prognosis for survival to discharge and racing performance in Thoroughbred foals treated for single joint septic arthritis (2009-2016)","volume":"55","author":"Whisenant KD","year":"2023","unstructured":"Whisenant KD, Ruggles AJ, Stefanovski D, Woodie JB, Hopper SA, Embertson RM. Prognosis for survival to discharge and racing performance in Thoroughbred foals treated for single joint septic arthritis (2009-2016). Equine Vet J. 2023;55(4):607-617. doi:10.1111\/evj.13892"},{"issue":"1","key":"ref6","series-title":"Equine Vet J","first-page":"84","article-title":"Bacteraemia in neonatal foals: clinicopathological differences between gram-positive and gram-negative infections, and single organism and mixed infections","volume":"39","author":"Corley KTT","year":"2007","unstructured":"Corley KTT, Pearce G, Magdesian KG, Wilson WD. Bacteraemia in neonatal foals: clinicopathological differences between gram-positive and gram-negative infections, and single organism and mixed infections. Equine Vet J. 2007;39(1):84-89. doi:10.2746\/042516407X157585"},{"issue":"5","key":"ref7","series-title":"J Vet Intern Med","first-page":"1203","article-title":"Bacteremia in equine neonatal diarrhea: a retrospective study (1990-2007)","volume":"22","author":"Hollis AR","year":"2008","unstructured":"Hollis AR, Wilkins PA, Palmer JE, Boston RC. Bacteremia in equine neonatal diarrhea: a retrospective study (1990-2007). J Vet Intern Med. 2008;22(5):1203-1209. doi:10.1111\/j.1939-1676.2008.0152.x"},{"issue":"2","key":"ref8","series-title":"J Vet Intern Med","first-page":"e70004","article-title":"The systemic inflammatory response syndrome and predictors of infection and mortality in 1068 critically ill newborn foals","volume":"39","author":"Wilkins PA","year":"2025","unstructured":"Wilkins PA, Wong D, Slovis NM, The systemic inflammatory response syndrome and predictors of infection and mortality in 1068 critically ill newborn foals. J Vet Intern Med. 2025;39(2):e70004. doi:10.1111\/jvim.70004"},{"issue":"5","key":"ref9","series-title":"J Vet Emerg Crit Care (San Antonio)","first-page":"660","article-title":"Retrospective evaluation of blood culture isolates and sepsis survival rate in foals in the Czech Republic: 50 cases (2011-2013)","volume":"25","author":"Hytychov\u00e1 T","year":"2015","unstructured":"Hytychov\u00e1 T, Bezd\u011bkov\u00e1 B. Retrospective evaluation of blood culture isolates and sepsis survival rate in foals in the Czech Republic: 50 cases (2011-2013). J Vet Emerg Crit Care (San Antonio). 2015;25(5):660-666. doi:10.1111\/vec.12348"},{"issue":"2","key":"ref10","series-title":"N Z Vet J","first-page":"107","article-title":"Antimicrobial susceptibility of bacteria isolated from neonatal foal samples submitted to a New Zealand veterinary pathology laboratory (2004 to 2013)","volume":"64","author":"Toombs-Ruane LJ","year":"2016","unstructured":"Toombs-Ruane LJ, Riley CB, Kendall AT, Hill KE, Benschop J, Rosanowski SM. Antimicrobial susceptibility of bacteria isolated from neonatal foal samples submitted to a New Zealand veterinary pathology laboratory (2004 to 2013). N Z Vet J. 2016;64(2):107-111. doi:10.1080\/00480169.2015.1109006"},{"issue":"3","key":"ref11","series-title":"J Vet Intern Med","first-page":"1193","article-title":"Antibiograms of field and hospital acquired equine neonatal bacterial fluid cultures in the Midwestern United States: 149 samples (2007-2018)","volume":"37","author":"Bookbinder LC","year":"2023","unstructured":"Bookbinder LC, Mani R, Carr EA. Antibiograms of field and hospital acquired equine neonatal bacterial fluid cultures in the Midwestern United States: 149 samples (2007-2018). J Vet Intern Med. 2023;37(3):1193-1200. doi:10.1111\/jvim.16671"},{"issue":"6","key":"ref12","series-title":"Crit Care Med","first-page":"1589","article-title":"Duration of hypotension before initiation of effective antimicrobial therapy is the critical determinant of survival in human septic shock","volume":"34","author":"Kumar A","year":"2006","unstructured":"Kumar A, Roberts D, Wood KE, Duration of hypotension before initiation of effective antimicrobial therapy is the critical determinant of survival in human septic shock. Crit Care Med. 2006;34(6):1589-1596. doi:10.1097\/01.CCM.0000217961.75225.E9"},{"key":"ref13","series-title":"Vet J","first-page":"74","article-title":"Initial antimicrobial treatment of foals with sepsis: do our choices make a difference?","volume":"243","author":"Theelen MJP","year":"2019","unstructured":"Theelen MJP, Wilson WD, Byrne BA, Edman JM, Kass PH, Magdesian KG. Initial antimicrobial treatment of foals with sepsis: do our choices make a difference? Vet J. 2019;243:74-76. doi:10.1016\/j.tvjl.2018.11.012"},{"issue":"2","key":"ref14","series-title":"J Vet Intern Med","first-page":"955","article-title":"Differences in isolation rate and antimicrobial susceptibility of bacteria isolated from foals with sepsis at admission and after \u226548 hours of hospitalization","volume":"34","author":"Theelen MJP","year":"2020","unstructured":"Theelen MJP, Wilson WD, Byrne BA, Differences in isolation rate and antimicrobial susceptibility of bacteria isolated from foals with sepsis at admission and after \u226548 hours of hospitalization. J Vet Intern Med. 2020;34(2):955-963. doi:10.1111\/jvim.15692"},{"issue":"2","key":"ref15","series-title":"Equine Vet J","first-page":"161","article-title":"Temporal trends in in vitro antimicrobial susceptibility patterns of bacteria isolated from foals with sepsis: 1979-2010","volume":"46","author":"Theelen MJP","year":"2014","unstructured":"Theelen MJP, Wilson WD, Edman JM, Magdesian KG, Kass PH. Temporal trends in in vitro antimicrobial susceptibility patterns of bacteria isolated from foals with sepsis: 1979-2010. Equine Vet J. 2014;46(2):161-168. doi:10.1111\/evj.12130"},{"issue":"11","key":"ref16","series-title":"Schweiz Arch Tierheilkd","first-page":"665","article-title":"Antimicrobial susceptibility patterns of blood culture isolates from foals in Switzerland","volume":"160","author":"Fouch\u00e9 N","year":"2018","unstructured":"Fouch\u00e9 N, Gerber V, Thomann A, Perreten V. Antimicrobial susceptibility patterns of blood culture isolates from foals in Switzerland. Schweiz Arch Tierheilkd. 2018;160(11):665-671. doi:10.17236\/sat00184"},{"issue":"9","key":"ref17","series-title":"Can Vet J","first-page":"951","article-title":"Antimicrobial resistance in bacteria isolated from horses from the Atlantic provinces, Canada (1994 to 2013)","volume":"59","author":"Awosile BB","year":"2018","unstructured":"Awosile BB, Heider LC, Saab ME, McClure JT. Antimicrobial resistance in bacteria isolated from horses from the Atlantic provinces, Canada (1994 to 2013). Can Vet J. 2018;59(9):951-957."},{"issue":"5","key":"ref18","series-title":"Can Vet J","first-page":"292","article-title":"Aerobic bacterial isolates in horses in a university hospital, 1986-1988","volume":"32","author":"Lavoie JP","year":"1991","unstructured":"Lavoie JP, Couture L, Higgins R, Laverty S. Aerobic bacterial isolates in horses in a university hospital, 1986-1988. Can Vet J. 1991;32(5):292-294."},{"issue":"7","key":"ref19","series-title":"Can Vet J","first-page":"747","article-title":"Evolution of in vitro antimicrobial resistance in an equine hospital over 3 decades","volume":"57","author":"Malo A","year":"2016","unstructured":"Malo A, Cluzel C, Labrecque O, Beauchamp G, Lavoie JP, Leclere M. Evolution of in vitro antimicrobial resistance in an equine hospital over 3 decades. Can Vet J. 2016;57(7):747-751."},{"issue":"2","key":"ref20","series-title":"Can Vet J","first-page":"153","article-title":"Bacterial isolates from equine infections in western Canada (1998-2003)","volume":"49","author":"Clark C","year":"2008","unstructured":"Clark C, Greenwood S, Boison JO, Chirino-Trejo M, Dowling PM. Bacterial isolates from equine infections in western Canada (1998-2003). Can Vet J. 2008;49(2):153-160."},{"issue":"1","key":"ref21","series-title":"BMC Vet Res","first-page":"479","article-title":"Extended spectrum \u03b2 lactamase-producing Enterobacteriaceae shedding by race horses in Ontario, Canada","volume":"16","author":"Shnaiderman-Torban A","year":"2020","unstructured":"Shnaiderman-Torban A, Navon-Venezia S, Paitan Y, Extended spectrum \u03b2 lactamase-producing Enterobacteriaceae shedding by race horses in Ontario, Canada. BMC Vet Res. 2020;16(1):479. doi:10.1186\/s12917-020-02701-z"},{"issue":"3","key":"ref22","series-title":"J Vet Intern Med","first-page":"1185","article-title":"Evaluation of updated sepsis scoring systems and systemic inflammatory response syndrome criteria and their association with sepsis in equine neonates","volume":"32","author":"Wong DM","year":"2018","unstructured":"Wong DM, Ruby RE, Dembek KA, Evaluation of updated sepsis scoring systems and systemic inflammatory response syndrome criteria and their association with sepsis in equine neonates. J Vet Intern Med. 2018;32(3):1185-1193. doi:10.1111\/jvim.15087"},{"issue":"3","key":"ref23","series-title":"Equine Vet J","first-page":"536","article-title":"Dorothy Russell Havemayer Working Group on Foal Sepsis. Report from the 2024 Dorothy Russell Havemeyer Working Group Meeting on consensus definitions for foal sepsis","volume":"57","author":"Wilkins PA","year":"2025","unstructured":"Wilkins PA, Wong DM; Dorothy Russell Havemayer Working Group on Foal Sepsis. Report from the 2024 Dorothy Russell Havemeyer Working Group Meeting on consensus definitions for foal sepsis. Equine Vet J. 2025;57(3):536-539. doi:10.1111\/evj.14443"},{"key":"ref24","article-title":"Performance Standards for Antimicrobial Disk and Dilution Susceptibility Tests for Bacteria Isolated From Animals","author":"Lubbers BV","year":"2018","unstructured":"Lubbers BV, Papich MG, Schwarz S, Performance Standards for Antimicrobial Disk and Dilution Susceptibility Tests for Bacteria Isolated From Animals. 4th ed. Clinical and Laboratory Standards Institute; 2018."},{"issue":"3","key":"ref25","series-title":"Clin Microbiol Infect","first-page":"268","article-title":"Multidrug-resistant, extensively drug-resistant and pandrug-resistant bacteria: an international expert proposal for interim standard definitions for acquired resistance","volume":"18","author":"Magiorakos AP","year":"2012","unstructured":"Magiorakos AP, Srinivasan A, Carey RB, Multidrug-resistant, extensively drug-resistant and pandrug-resistant bacteria: an international expert proposal for interim standard definitions for acquired resistance. Clin Microbiol Infect. 2012;18(3):268-281. doi:10.1111\/j.1469-0691.2011.03570.x"},{"key":"ref26","article-title":"Modern Applied Statistics with S","author":"Venables WN","year":"2002","unstructured":"Venables WN, Ripley BD. Modern Applied Statistics with S. 4th ed. Springer; 2002. doi:10.1007\/978-0-387-21706-2"},{"key":"ref27","article-title":"R version 4.4.1","year":"2024","unstructured":"R: A Language and Environment for Statistical Computing. R version 4.4.1, R Core Team; 2024. Accessed October 30, 2024. https:\/\/cran.r-project.org\/manuals.html"},{"key":"ref28","series-title":"Equine Infectious Diseases","first-page":"265","article-title":"Streptococcal infections","author":"Waller AS","year":"2014","unstructured":"Waller AS, Sellon DC, Sweeney CR, Streptococcal infections. In: Equine Infectious Diseases. Elsevier; 2014:265\u2013277. doi:10.1016\/B978-1-4557-0891-8.00028-2"},{"issue":"22","key":"ref29","series-title":"Vet Rec","first-page":"543","article-title":"Umbilical infections in foals: microbiological investigation and management","volume":"180","author":"Rampacci E","year":"2017","unstructured":"Rampacci E, Passamonti F, Bottinelli M, Umbilical infections in foals: microbiological investigation and management. Vet Rec. 2017;180(22):543. doi:10.1136\/vr.103999"},{"key":"ref30","series-title":"PeerJ","first-page":"e13682","article-title":"Antimicrobial resistance among Streptococcus equi subspecies zooepidemicus and Rhodococcus equi isolated from equine specimens submitted to a diagnostic laboratory in Kentucky, USA","volume":"10","author":"Lord J","year":"2022","unstructured":"Lord J, Carter C, Smith J, Locke S, Phillips E, Odoi A. Antimicrobial resistance among Streptococcus equi subspecies zooepidemicus and Rhodococcus equi isolated from equine specimens submitted to a diagnostic laboratory in Kentucky, USA. PeerJ. 2022;10:e13682. doi:10.7717\/peerj.13682"},{"key":"ref31","series-title":"Prev Vet Med","first-page":"105857","article-title":"Antimicrobial susceptibility of Salmonella and Escherichia coli from equids sampled in the NAHMS 2015-16 equine study and association of management factors with resistance","volume":"213","author":"Kohnen AB","year":"2023","unstructured":"Kohnen AB, Wiedenheft AM, Traub-Dargatz JL, Antimicrobial susceptibility of Salmonella and Escherichia coli from equids sampled in the NAHMS 2015-16 equine study and association of management factors with resistance. Prev Vet Med. 2023;213:105857. doi:10.1016\/j.prevetmed.2023.105857"},{"key":"ref32","series-title":"Vet J","first-page":"42","article-title":"Enterococcus infections in foals","volume":"248","author":"Willis AT","year":"2019","unstructured":"Willis AT, Magdesian KG, Byrne BA, Edman JM. Enterococcus infections in foals. Vet J. 2019;248:42-47. doi:10.1016\/j.tvjl.2019.04.005"},{"issue":"6","key":"ref33","series-title":"Equine Vet Educ","first-page":"328","article-title":"Antimicrobial therapy for multidrug resistant pathogens","volume":"21","author":"Weese JS","year":"2009","unstructured":"Weese JS. Antimicrobial therapy for multidrug resistant pathogens. Equine Vet Educ. 2009;21(6):328-334. doi:10.2746\/095777308X334293"},{"issue":"1","key":"ref34","series-title":"Antimicrob Resist Infect Control","first-page":"130","article-title":"Enterococcus faecium: from microbiological insights to practical recommendations for infection control and diagnostics","volume":"9","author":"Zhou X","year":"2020","unstructured":"Zhou X, Willems RJL, Friedrich AW, Rossen JWA, Bathoorn E. Enterococcus faecium: from microbiological insights to practical recommendations for infection control and diagnostics. Antimicrob Resist Infect Control. 2020;9(1):130. doi:10.1186\/s13756-020-00770-1"},{"issue":"12","key":"ref35","series-title":"J Equine Vet Sci","first-page":"1057","article-title":"Genomic description of antibiotic resistance in Escherichia coli and Enterococci isolates from healthy Lusitano horses","volume":"33","author":"Moura I","year":"2013","unstructured":"Moura I, Torres C, Silva N, Somalo S, Igrejas G, Poeta P. Genomic description of antibiotic resistance in Escherichia coli and Enterococci isolates from healthy Lusitano horses. J Equine Vet Sci. 2013;33(12):1057-1063. doi:10.1016\/j.jevs.2013.04.002"},{"key":"ref36","series-title":"J Clin Microbiol","first-page":"e02210","article-title":"What\u2019s new in antibiograms? Updating CLSI M39 guidance with current trends","volume":"60","author":"Simner PJ","year":"2022","unstructured":"Simner PJ, Hindler JA, Bhowmick T, What\u2019s new in antibiograms? Updating CLSI M39 guidance with current trends. J Clin Microbiol. 2022;60:e02210-21. doi:10.1128\/jcm.02210-21"},{"issue":"2","key":"ref37","series-title":"J Vet Intern Med","first-page":"487","article-title":"ACVIM consensus statement on therapeutic antimicrobial use in animals and antimicrobial resistance","volume":"29","author":"Weese JS","year":"2015","unstructured":"Weese JS, Gigu\u00e8re S, Guardabassi L, ACVIM consensus statement on therapeutic antimicrobial use in animals and antimicrobial resistance. 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