{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,13]],"date-time":"2026-05-13T01:23:56Z","timestamp":1778635436614,"version":"3.51.4"},"reference-count":40,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2019,8,23]],"date-time":"2019-08-23T00:00:00Z","timestamp":1566518400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Extended-spectrum \u03b2-lactamase Enterobacteriaceae (ESBL-E) have been investigated in adult horses, but not in foals. We aimed to determine shedding and infection in neonatal foals and mares. Rectal swabs were sampled from mare and foal pairs on admission and on the 3rd day of hospitalization; enriched, plated, and bacteria were verified for ESBL production. Identification and antibiotic susceptibility profiles were determined (Vitek2). Genotyping was performed by multilocus sequence typing (MLST). Genes were identified by PCR and Sanger sequencing. Medical data were analyzed for risk factors (SPSS). On admission, 55 pairs were sampled, of which 33 pairs were re-sampled. Shedding rates on admission in foals and mares were 33% (95% CI 21\u201347%) and 16% (95% CI 8\u201329%), respectively, and during hospitalization, these increased significantly to 85% (95% CI 70\u201394%) and 58% (95% CI 40\u201373%), respectively. Foal shedding was associated with umbilical infection on admission (P = 0.016) and with ampicillin treatment during hospitalization (p = 0.011), and was independent of the mare\u2019s shedding. The most common ESBL-E was Escherichia coli. During hospitalization, species diversity increased. Four foals were infected with ESBL-E strains, including umbilical infections and wounds. This study substantiates an alarming prevalence of shedding in neonatal foals, which should be further investigated in order to reduce resistance rates.<\/jats:p>","DOI":"10.3390\/ani9090600","type":"journal-article","created":{"date-parts":[[2019,8,26]],"date-time":"2019-08-26T04:38:23Z","timestamp":1566794303000},"page":"600","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["Extended-Spectrum \u03b2-Lactamase-Producing Enterobacteriaceae in Hospitalized Neonatal Foals: Prevalence, Risk Factors for Shedding and Association with Infection"],"prefix":"10.3390","volume":"9","author":[{"given":"Anat","family":"Shnaiderman-Torban","sequence":"first","affiliation":[{"name":"Koret School of Veterinary Medicine (KSVM), The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 761001, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yossi","family":"Paitan","sequence":"additional","affiliation":[{"name":"Department of Clinical Microbiology and Immunology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel"},{"name":"Clinical Microbiology Lab, Meir Medical Center, Kfar Saba 4428164, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Haia","family":"Arielly","sequence":"additional","affiliation":[{"name":"Clinical Microbiology Lab, Meir Medical Center, Kfar Saba 4428164, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kira","family":"Kondratyeva","sequence":"additional","affiliation":[{"name":"Department of Molecular Biology, Faculty of Natural Science, Ariel University, Ariel 40700, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3810-8418","authenticated-orcid":false,"given":"Sharon","family":"Tirosh-Levy","sequence":"additional","affiliation":[{"name":"Koret School of Veterinary Medicine (KSVM), The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 761001, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gila","family":"Abells-Sutton","sequence":"additional","affiliation":[{"name":"Koret School of Veterinary Medicine (KSVM), The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 761001, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shiri","family":"Navon-Venezia","sequence":"additional","affiliation":[{"name":"Department of Molecular Biology, Faculty of Natural Science, Ariel University, Ariel 40700, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0984-6822","authenticated-orcid":false,"given":"Amir","family":"Steinman","sequence":"additional","affiliation":[{"name":"Koret School of Veterinary Medicine (KSVM), The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 761001, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,8,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"10","DOI":"10.1016\/j.vetmic.2014.01.017","article-title":"Extended-spectrum \u03b2-lactamase, carbapenemase and AmpC producing Enterobacteriaceae in companion animals","volume":"170","author":"Rubin","year":"2014","journal-title":"Vet. Microbiol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"216","DOI":"10.1002\/med.20210","article-title":"New definitions of extended-spectrum \u03b2-lactamase conferring worldwide emerging antibiotic resistance","volume":"32","author":"Lee","year":"2012","journal-title":"Med. Res. Rev."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Liu, X., Thungrat, K., and Boothe, D.M. (2016). 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