{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,5]],"date-time":"2026-08-05T00:45:47Z","timestamp":1785890747975,"version":"3.56.0"},"reference-count":52,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2023,10,17]],"date-time":"2023-10-17T00:00:00Z","timestamp":1697500800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the Veterinary Medicine Directorate","award":["VM0536"],"award-info":[{"award-number":["VM0536"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>Time-kill curves (TKCs) are more informative compared with the use of minimum inhibitory concentration (MIC) as they allow the capture of bacterial growth and the development of drug killing rates over time, which allows to compute key pharmacodynamic (PD) parameters. Our study aimed, using a semi-mechanistic mathematical model, to estimate the best pharmacokinetic\/pharmacodynamic (PK\/PD) indices (\u0192AUC\/MIC or %\u0192T &gt; MIC) for the prediction of clinical efficacy of veterinary FQs in Staphylococcus pseudintermedius, Staphylococcus aureus, and Escherichia coli collected from canine pyoderma cases with a focus on the comparison between marbofloxacin and pradofloxacin. Eight TCKs for each bacterial species (4 susceptible and 4 resistant) were analysed in duplicate. The best PK\/PD index was \u0192AUC24h\/MIC in both staphylococci and E. coli. For staphylococci, values of 25\u201340 h were necessary to achieve a bactericidal effect, whereas the calculated values (25\u201335 h) for E. coli were lower than those predicting a positive clinical outcome (100\u2013120 h) in murine models. Pradofloxacin showed a higher potency (lower EC50) in comparison with marbofloxacin. However, no difference in terms of a maximal possible pharmacological killing rate (Emax) was observed. Taking into account in vivo exposure at the recommended dosage regimen (3 and 2 mg\/kg for pradofloxacin and marbofloxacin, respectively), the overall killing rates (Kdrug) computed were also similar in most instances.<\/jats:p>","DOI":"10.3390\/antibiotics12101548","type":"journal-article","created":{"date-parts":[[2023,10,17]],"date-time":"2023-10-17T08:08:33Z","timestamp":1697530113000},"page":"1548","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Time-Kill Analysis of Canine Skin Pathogens: A Comparison of Pradofloxacin and Marbofloxacin"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0009-0007-9293-5266","authenticated-orcid":false,"given":"Stefano","family":"Azzariti","sequence":"first","affiliation":[{"name":"Department of Comparative Biomedical Sciences, Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield AL9 7TA, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrew","family":"Mead","sequence":"additional","affiliation":[{"name":"Department of Comparative Biomedical Sciences, Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield AL9 7TA, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pierre-Louis","family":"Toutain","sequence":"additional","affiliation":[{"name":"Department of Comparative Biomedical Sciences, Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield AL9 7TA, UK"},{"name":"INTHERES, Universit\u00e9 de Toulouse, INRAE, Ecole Nationale V\u00e9t\u00e9rinaire de Toulouse, 23 chemin des Capelles-BP 87614, CEDEX 03, 31076 Toulouse, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ross","family":"Bond","sequence":"additional","affiliation":[{"name":"Department of Clinical Sciences and Services, Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield AL9 7TA, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6005-1975","authenticated-orcid":false,"given":"Ludovic","family":"Pelligand","sequence":"additional","affiliation":[{"name":"Department of Comparative Biomedical Sciences, Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield AL9 7TA, UK"},{"name":"Department of Clinical Sciences and Services, Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield AL9 7TA, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,10,17]]},"reference":[{"key":"ref_1","unstructured":"EUCAST (2023, July 01). 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