{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T17:15:04Z","timestamp":1790702104967,"version":"4.1.0"},"reference-count":39,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2021,8,20]],"date-time":"2021-08-20T00:00:00Z","timestamp":1629417600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Spanish Ministry of Economy and Competitiveness; FEDER; French Ministry for Agriculture and Food","award":["FPU UMU 2015"],"award-info":[{"award-number":["FPU UMU 2015"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Contagious agalactia is associated with mastitis, keratoconjunctivitis, arthritis, pneumonia, and septicemia in small ruminants in countries with large dairy industries worldwide. The causative agents belong to four (sub)species of the Mycoplasma genus that have remained essentially susceptible to antimicrobials, including to the widely-used tetracycline family. However, some clinical isolates have been detected that show increased minimum inhibitory concentrations of tetracyclines, although they do not harbor the mutation in the 16SrRNA gene usually associated with resistance. The present work aimed to assess whether efflux pumps, infrequently described in mycoplasmas, could participate in the observed moderate loss of susceptibility. General efflux mechanisms were measured (i) using the fluorescence property of ethidium bromide when accumulated intracellularly and intercalated in the mycoplasma genomes, its active extrusion resulting in a temperature-dependent decrease in fluorescence and (ii) monitoring the growth inhibition of mycoplasmas by subinhibitory concentrations of tetracycline with or without reserpine, a known inhibitor of efflux in other bacteria. Both methods revealed non-specific efflux phenomena in most of the isolates tested, although their efficacy was difficult to quantify. This property could contribute to the acquisition of mutations conferring resistance by maintaining intracellular concentrations of tetracyclines at subinhibitory levels.<\/jats:p>","DOI":"10.3390\/ani11082449","type":"journal-article","created":{"date-parts":[[2021,8,20]],"date-time":"2021-08-20T08:44:45Z","timestamp":1629449085000},"page":"2449","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Efflux Might Participate in Decreased Susceptibility to Oxytetracycline in Contagious Agalactia-Causative Mycoplasma spp."],"prefix":"10.3390","volume":"11","author":[{"given":"Juan","family":"Tatay-Dualde","sequence":"first","affiliation":[{"name":"Ruminant Health Research Group, Faculty of Veterinary Sciences, Regional Campus of International Excellence \u201cCampus Mare Nostrum\u201d, Campus de Espinardo s\/n, University of Murcia, 30100 Murcia, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Miranda","family":"Prats-van der Ham","sequence":"additional","affiliation":[{"name":"Ruminant Health Research Group, Faculty of Veterinary Sciences, Regional Campus of International Excellence \u201cCampus Mare Nostrum\u201d, Campus de Espinardo s\/n, University of Murcia, 30100 Murcia, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Patrice","family":"Gaurivaud","sequence":"additional","affiliation":[{"name":"UMR Mycoplasmoses Animales, Anses, VetAgro Sup, Universit\u00e9 de Lyon, F-69364 Lyon, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4354-1689","authenticated-orcid":false,"given":"Christian","family":"de la Fe","sequence":"additional","affiliation":[{"name":"Ruminant Health Research Group, Faculty of Veterinary Sciences, Regional Campus of International Excellence \u201cCampus Mare Nostrum\u201d, Campus de Espinardo s\/n, University of Murcia, 30100 Murcia, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3968-4801","authenticated-orcid":false,"given":"Florence","family":"Tardy","sequence":"additional","affiliation":[{"name":"UMR Mycoplasmoses Animales, Anses, VetAgro Sup, Universit\u00e9 de Lyon, F-69364 Lyon, France"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,8,20]]},"reference":[{"key":"ref_1","first-page":"229","article-title":"Contagious Agalactia In Sheep and Goats: Current Perspectives","volume":"10","author":"Tardy","year":"2019","journal-title":"Vet. 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