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Minimum Inhibitory Concentration (MIC) data for third generation cephalosporin resistant E. coli and extended spectrum beta-lactamase producing Enterobacteriaceae from feedlot cattle

    The data presents the antimicrobial susceptibility testing results in three separate files: 1) third generation cephalosporin resistant E. coli isolates obtained on cefotaxime supplemented media; 2) extended spectrum beta-lactamase (ESBL) producing E. coli, and 3) ESBL-producing Klebsiella, Enterobacter and Citrobacter species obtained on chromogenic media. The data was generated as part of a research project that evaluated the impact of tylosin supplementation of feedlot cattle on the dynamics of antimicrobial resistant fecal bacteria. The study was a longitudinal design with periodic sampling of fecal samples from individual animals over the entire feeding period.

    Comparison of methods to detect low levels of Salmonella enterica in surface waters to support antimicrobial resistance surveillance efforts performed in multiple laboratories

      Identifying and developing effective and sensitive detection methods for antimicrobial resistant Salmonella enterica from surface water is a goal of the U.S. National Antimicrobial Resistance Monitoring System (NARMS). No specific microbiological methods used in surveillance efforts for Salmonella enterica or antimicrobial resistant S. enterica in water have been standardized or reported in the U.S. Here we describe a multi-laboratory evaluation of four methods, bulk water enrichment (BW), vertical Modified Moore Swab (VMMS), modified Standard Method 9260.B3 (SM), and dead-end ultrafiltration (DEUF), to recover S. enterica from surface water.

      Agricultural Collaborative Research Outcomes System (AgCROS)

        The Agricultural Collaborative Research Outcomes System (AgCROS) is a growing “network of networks” that presently consists of multiple agricultural data networks: Nutrient Uptake and Outcome Network (NUOnet), the Greenhouse gas Reduction through Agricultural Carbon Enhancement Network (GRACEnet), Resilient Economic Agricultural Practices (REAP), Dairy Agriculture for People and the Planet (DAPP; Dairy Grand Challenge), Soil Health Assessment Network (SHAnet), Agricultural Antibiotic Resistance (AgAR), and the Long-Term Agroecosystem Research (LTAR) Network. By integrating these diverse database networks, AgCROS facilitates the flow of information and increases the cooperation among researchers participating in these networks.

        2014 Swine CAFO Study SE for Agricultural Antibiotic Resistance in Mississippi State, Mississippi

          The purpose of this study was to measure the microbial constituents of swine-sow, -nursery, and -finisher farm manure lagoon wastewater and determine the changes induced by farm management. A total of 37 farms were visited in the Mid-South USA and analyzed for the genes 16S rRNA, spaQ (Salmonella spp.), Camp-16S (Campylobacter spp.), tetA, tetB, ermF, ermA, mecA, and intI using quantitative PCR. Additionally, 16S rRNA sequence libraries were created.

          Nebraska Prairie Study for Agricultural Antibiotic Resistance in Lincoln, Nebraska

            The inherent spatial heterogeneity and complexity of antibiotic resistant bacteria and antibiotic resistance (AR) genes in manureaffected soils makes it difficult to sort out resistance that can be attributed to human antibiotic use from resistance that occurs naturally in the soil. This study characterizes native Nebraska prairie soils that have not been affected by human or food-animal waste products to provide data on background levels of resistance in southeastern Nebraskan soils.

            IncA-C Alignment

              IncA/C plasmids are a class of plasmids from Enterobacteraciae that are relatively large (49 to >180 kbp), are readily transferred by conjugation, and carry multiple antimicrobial resistance genes. Reconstruction of the phylogeny of these plasmids has been difficult because of the high rate of remodeling by recombination-mediated horizontal gene transfer (HGT). We hypothesized that evaluation of nucleotide polymorphisms relative to the rate of HGT would help to develop a clock to show if anthropic practices have had significant influences on the lineages of the plasmid. A system was developed to rapidly sequence up to 191 known open27 reading-frames from each of 39 recently isolated IncA/C plasmids from a diverse panel of Salmonella enterica and Escherichia coli. With these data plus sequences from Genbank we were able to distinguish six distinct lineages that had extremely low numbers of polymorphisms within each lineage, especially among the largest group designated as Lineage 1. Two regions, each about half the plasmid in size, could be distinguished with a separate lineal pattern. The distribution of Lineage 1 showed that it has migrated extremely rapidly with fewer polymorphisms than can be expected in two-thousand years. Remodeling by frequent HGT was evident with a pattern that appeared to have the highest rate just upstream of the putative conjugation origin of transfer (ori-T). It seems likely that when an IncA/C plasmid is transferred also adjacent to a multiple antimicrobial resistance gene cassette.