Effects of Tylosin, a Direct-Fed Microbial and Feedlot Pen Environment on Phenotypic Resistance among Enterococci Isolated from Beef Cattle Feces.
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ABSTRACT:
SUBMITTER: Murray SA
PROVIDER: S-EPMC8772914 | biostudies-literature | 2022 Jan
REPOSITORIES: biostudies-literature
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Effects of Tylosin, a Direct-Fed Microbial and Feedlot Pen Environment on Phenotypic Resistance among Enterococci Isolated from Beef Cattle Feces.
Murray Sarah A SA Holbert Ashlyn C AC Norman Keri N KN Lawhon Sara D SD Sawyer Jason E JE Scott Harvey M HM
Antibiotics (Basel, Switzerland) 20220114 1
In two sequential replicates (<i>n</i> = 90 and <i>n</i> = 96 feedlot finisher cattle, respectively) we measured the impact of an <i>Enterococcus faecium</i>-based probiotic (DFM) and an altered feedlot pen environment on antimicrobial resistance among fecal enterococci in cattle fed (or, not fed) the macrolide tylosin. Diluted fecal samples were spiral-plated on plain and antibiotic-supplemented m-<i>Enterococcus</i> agar. In the first replicate, tylosin significantly (<i>p</i> < 0.05) increase ...[more]
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