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Epidemiology, Impact and Mitigation of Antimicrobial Resistance in Veterinary Medicine

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A special issue of Antibiotics (ISSN 2079-6382). This special issue belongs to the section "Antibiotics in Animal Health".

Deadline for manuscript submissions: closed (30 June 2022) | Viewed by 26302

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Special Issue Editor

Dr. Robin Temmerman

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Guest Editor

Veterinary Medicine Research & Development, Regulatory Affairs, Zoetis, Mercuriusstraat 20, 1930 Zaventem, Belgium
Interests: antimicrobial resistance; veterinary pharmacology and toxicology; PK/PD modelling; regulatory affairs
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Antimicrobial agents are progressively losing efficacy in treating bacterial infections due to the seemingly unstoppable rise in antimicrobial resistance (AMR). The past few decades saw the rise of (multi-)resistant bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus (VRE), carbapenem-resistant Enterobacteriaceae (CRE), and fluoroquinolone-resistant peusdomonas aeruginosa. The increasing and alarming levels of AMR are strongly associated with the use and consumption of antimicrobial agents. Treatment failure in veterinary medicine has negative repercussions on animal welfare and animal health and productivity in the case of food-producing animals. Importantly, animals, humans, and their shared environment are inextricably linked, something which has been described as the One Health concept. With respect to AMR, this implies that resistant bacteria and antimicrobial resistance genes can propagate between humans and animals via myriad complex interactions, unveiling AMR as a truly multifaceted threat.

Therefore, the main subjects of this Special Issue include the epidemiology and surveillance of AMR, the mechanisms and evolution of resistance, clinical applications of existing and newer antimicrobials, approaches to improve the judicious use of antimicrobials, and strategies to curb the emergence and dissemination of resistance in veterinary medicine, both in companion and food-producing animals. Additionally, submissions concerning the assessment of the One health impact of antimicrobial treatment are accepted.

Dr. Robin Temmerman
Guest Editor

Manuscript Submission Information

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Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Antibiotics is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2900 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

Antimicrobial resistance
Veterinary medicine
Antibiotics
One Health
Epidemiology

Published Papers (11 papers)

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Research

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19 pages, 1197 KiB

Open AccessArticle

Genomic Insights into Methicillin-Resistant Staphylococci and Mammaliicocci from Bulk Tank Milk of Dairy Farms in Serbia

by Andrea Kos, Bojan Papić, Majda Golob, Jana Avberšek, Darja Kušar, Tijana Ledina, Jasna Đorđević and Snežana Bulajić

Antibiotics 2023, 12(10), 1529; https://doi.org/10.3390/antibiotics12101529 - 11 Oct 2023

Viewed by 1662

Abstract

The potential risk to human and animal health provides a rationale for research on methicillin-resistant staphylococci (MRS) and mammaliicocci (MRM) in dairy herds. Here, we aimed to estimate their occurrence in the bulk tank milk (BTM) samples collected in 2019–2021 from 283 bovine dairy farms in the Belgrade district. We used whole-genome sequencing to characterize the obtained isolates and assess their genetic relatedness. A total of 70 MRS/MRM were recovered, most frequently Staphylococcus haemolyticus and Mammaliicoccus sciuri. Five clusters of 2–4 genetically related isolates were identified and epidemiological data indicated transmission through, e.g., farm visits by personnel or milk collection trucks. Most MRSA isolates belonged to the typical livestock-associated lineage ST398-t034. One MRSA isolate (ST152-t355) harbored the PVL-encoding genes. Since MRS/MRM isolates obtained in this study frequently harbored genes conferring multidrug resistance (MDR), this argues for their role as reservoirs for the spread of antimicrobial resistance genes. The pipeline milking system and total bacterial count >100,000 CFU/mL were significantly associated with higher occurrences of MRS/MRM. Our study confirms that BTM can be a zoonotic source of MRS, including MDR strains. This highlights the urgent need for good agricultural practices and the continuous monitoring of MRS/MRM in dairy farms. Full article

(This article belongs to the Special Issue Epidemiology, Impact and Mitigation of Antimicrobial Resistance in Veterinary Medicine)

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13 pages, 4112 KiB

Open AccessArticle

Emergence and Genomic Features of a mcr-1 Escherichia coli from Duck in Hungary

by Ama Szmolka, Ákos Gellért, Dóra Szemerits, Fanni Rapcsák, Sándor Spisák and András Adorján

Antibiotics 2023, 12(10), 1519; https://doi.org/10.3390/antibiotics12101519 - 7 Oct 2023

Viewed by 1742

Abstract

Plasmids carrying high-risk resistance mechanisms in pathogenic E. coli have gained particular attention in veterinary medicine, especially since the discovery of the colistin resistance gene, mcr-1. Here, we provide the first evidence of its emergence and describe the complete mcr-1 plasmid sequence of a multi-resistant avian pathogenic E. coli (APEC) strain from waterfowl in Hungary. Whole-genome sequencing analysis and core-genome MLST were performed to characterize the genome structure of the mcr-1 plasmid and to reveal the phylogenetic relation between the Hungarian duck strain Ec45-2020 and the internationally circulating mcr-1-positive E. coli strains from poultry and humans. Results showed that plasmid pEc45-2020-33kb displayed a high level of genome identity with mcr-1 plasmids of IncX4 type widespread among human, animal and food reservoirs of enteric bacteria of public health. The mcr-1-positive E. coli strain Ec45-2020 belongs to the ST162 genotype, considered as one of the globally disseminated zoonotic genotypes of MDR E. coli. In accordance with international findings, our results underline the importance of continuous surveillance of enteric bacteria with high-risk antimicrobial resistance genotypes, including neglected animals, such as waterfowls, as possible reservoirs for the colistin resistance gene mcr-1. Full article

(This article belongs to the Special Issue Epidemiology, Impact and Mitigation of Antimicrobial Resistance in Veterinary Medicine)

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12 pages, 1321 KiB

Open AccessArticle

Antimicrobial Resistance Trends of Escherichia coli Isolates: A Three-Year Prospective Study of Poultry Production in Spain

by Sandra Sevilla-Navarro, Pablo Catalá-Gregori, Jan Torres-Boncompte, Maria Teresa Orenga, Josep Garcia-Llorens and Verónica Cortés

Antibiotics 2022, 11(8), 1064; https://doi.org/10.3390/antibiotics11081064 - 5 Aug 2022

Cited by 3 | Viewed by 2558

Abstract

Antimicrobial resistance (AMR) poses a major threat to health worldwide. Poultry products are one of the main threats, due to the transmission of antimicrobial resistance genes throughout the food chain. Escherichia coli is the main cause of mortality in the poultry industry, mainly mitigated with antibiotics, but due to the high genetic strain variability, recurrent outbreaks of multidrug resistant E. coli take place. The major challenge to tackling AMR is understanding the burden of resistance. For this reason, one of the main strategies is monitoring AMR by phenotypic characterisation. Our study aimed to monitor the resistance of E. coli strains isolated from the poultry sector over a period of three years (2019–2021) to provide information on the resistance magnitude and trends. Promising results have been found concerning the low frequency of resistance to cephalosporins, polymyxin, and fluoroquinolones. However, levels of resistance found to antimicrobials such as erythromycin (100%), tylosin (98%), or penicillin (97%) suggest the need to continue working on the limitation of use of antimicrobials in poultry to achieve the demise of MDR. Full article

(This article belongs to the Special Issue Epidemiology, Impact and Mitigation of Antimicrobial Resistance in Veterinary Medicine)

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16 pages, 1632 KiB

Open AccessArticle

The Monitoring of Mycoplasma gallisepticum Minimum Inhibitory Concentrations during the Last Decade (2010–2020) Seems to Reveal a Comeback of Susceptibility to Macrolides, Tiamulin, and Lincomycin

by Marco Bottinelli, Michele Gastaldelli, Micaela Picchi, Arianna Dall’Ora, Lorena Cristovao Borges, Ana Sofía Ramírez, Andrea Matucci and Salvatore Catania

Antibiotics 2022, 11(8), 1021; https://doi.org/10.3390/antibiotics11081021 - 29 Jul 2022

Cited by 6 | Viewed by 2511

Abstract

Mycoplasma gallisepticum (Mg) is a highly contagious avian pathogen responsible for significant economic losses for the poultry industry. In some circumstances, antimicrobial treatment is useful to contain clinical signs of Mg infection in birds. However, antimicrobial resistance emergence is now common among animal pathogens, becoming a worldwide health concern. The collection of minimum inhibitory concentration (MIC) data is fundamental for an appropriate antimicrobial use and for fighting antimicrobial resistance emergence. However, MIC data can only be generated in specialized laboratories, and therefore they are not regularly available. MICs of 67 non-vaccine-derived Mg isolates collected in Italy between 2010 and 2020 were obtained. Although 79.1% of the Mg isolates showed enrofloxacin MICs ≥ 8 µg/mL, a statistically significant trend toward low MICs of erythromycin, tylosin, tilmicosin, spiramycin, tiamulin, and lincomycin was observed, indicating a comeback to susceptibility of Mg toward these drugs. Doxycycline proved to be slightly more effective than oxytetracycline. The present study shows that Mg changed its susceptibility toward many of the drugs most commonly used for its containment over a ten-year period. Full article

(This article belongs to the Special Issue Epidemiology, Impact and Mitigation of Antimicrobial Resistance in Veterinary Medicine)

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16 pages, 4203 KiB

Open AccessArticle

Epidemiological Prevalence of Phenotypical Resistances and Mobilised Colistin Resistance in Avian Commensal and Pathogenic E. coli from Denmark, France, The Netherlands, and the UK

by Andrew Mead, Candice Billon-Lotz, Rikke Olsen, Ben Swift, Pascal Richez, Richard Stabler and Ludovic Pelligand

Antibiotics 2022, 11(5), 631; https://doi.org/10.3390/antibiotics11050631 - 7 May 2022

Cited by 6 | Viewed by 1995

Abstract

Colistin has been used for the treatment of non-invasive gastrointestinal infections caused by avian pathogenic E. coli (APEC). The discovery of mobilised colistin resistance (mcr) in E. coli has instigated a One Health approach to minimise colistin use and the spread of resistance. The aim of this study was to compare colistin susceptibility of APECs (collected from Denmark n = 25 and France n = 39) versus commensal E. coli (collected from the Netherlands n = 51 and the UK n = 60), alongside genetic (mcr-1–5) and phenotypic resistance against six other antimicrobial classes (aminoglycosides, cephalosporins, fluoroquinolones, penicillins, sulphonamides/trimethoprim, tetracyclines). Minimum inhibitory concentration (MIC) values were determined using a broth microdilution method (EUCAST guidelines), and phenotypic resistance was determined using disk diffusion. Colistin MIC values of APEC were significantly lower than those for commensals by 1 dilution (p < 0.0001, Anderson-Darling test), and differences in distributions were observed between countries. No isolate carried mcr-1–5. Three phenotypically resistant isolates were identified in 2/62 APEC and 1/111 commensal isolates. Gentamicin or gentamicin–ceftriaxone co-resistance was observed in two of these isolates. This study showed a low prevalence of phenotypic colistin resistance, with no apparent difference in colistin resistance between commensal E. coli strains and APEC strains. Full article

(This article belongs to the Special Issue Epidemiology, Impact and Mitigation of Antimicrobial Resistance in Veterinary Medicine)

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20 pages, 1872 KiB

Open AccessArticle

Prevalence, Mechanism, Genetic Diversity, and Cross-Resistance Patterns of Methicillin-Resistant Staphylococcus Isolated from Companion Animal Clinical Samples Submitted to a Veterinary Diagnostic Laboratory in the Midwestern United States

by Mehmet Cemal Adiguzel, Kayla Schaefer, Trevor Rodriguez, Jessica Ortiz and Orhan Sahin

Antibiotics 2022, 11(5), 609; https://doi.org/10.3390/antibiotics11050609 - 30 Apr 2022

Cited by 5 | Viewed by 2266

Abstract

Methicillin-resistant Staphylococcus (MRS) is a leading cause of skin and soft tissue infections in companion animals, with limited treatment options available due to the frequent cross-resistance of MRS to other antibiotics. In this study, we report the prevalence, species distribution, genetic diversity, resistance mechanism and cross-resistance patterns of MRS isolated from companion animal (mostly dog and cat) clinical cases submitted to Iowa State University Veterinary Diagnostic Laboratory (ISU VDL) between 2012 and 2019. The majority of isolates were identified as Staphylococcus pseudintermedius (68.3%; 2379/3482) and coagulase-negative Staphylococcus (CoNS) (24.6%; 857/3482), of which 23.9% and 40.5% were phenotypically resistant to methicillin, respectively. Cross resistance to other β-lactams (and to a lesser extent to non-β-lactams) was common in both methicillin-resistant S. pseudintermedius (MRSP) and CoNS (MRCoNS), especially when oxacillin MIC was ≥4 μg/mL (vs. ≥0.5–<4 μg/mL). The PBP2a protein was detected by agglutination in 94.6% (521/551) MRSP and 64.3% (146/227) MRCoNS. A further analysis of 31 PBP2a-negative MRS isolates (all but one MRCoNS) indicated that 11 were mecA gene-positive while 20 were negative for mecA and other mec genes by PCR. The resistance to last-resort anti-staphylococcal human drugs (e.g., tigecycline, linezolid, vancomycin) among the MRS tested was none to very low. Even though genotyping indicated an overall high level of genetic diversity (87 unique PFGE patterns and 20 MLST types) among a subset of MRSP isolates tested (n = 106), certain genotypes were detected from epidemiologically connected cases at the same or different time points, suggesting persistence and/or nosocomial transmission. These results indicate a relatively high prevalence of MRS from companion animals in the Midwestern US; therefore, it is important to perform routine susceptibility testing of Staphylococcus in veterinary clinical settings for the selection of appropriate antimicrobial therapy. Full article

(This article belongs to the Special Issue Epidemiology, Impact and Mitigation of Antimicrobial Resistance in Veterinary Medicine)

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17 pages, 1901 KiB

Open AccessArticle

Effect of Danofloxacin Treatment on the Development of Fluoroquinolone Resistance in Campylobacter jejuni in Calves

by Debora Brito Goulart, Ashenafi Feyisa Beyi, Zuowei Wu, Mehmet Cemal Adiguzel, Anastasia Schroeder, Kritika Singh, Changyun Xu, Melda Meral Ocal, Renee Dewell, Grant A. Dewell, Paul J. Plummer, Qijing Zhang and Orhan Sahin

Antibiotics 2022, 11(4), 531; https://doi.org/10.3390/antibiotics11040531 - 15 Apr 2022

Cited by 5 | Viewed by 2193

Abstract

Campylobacter is a leading cause of foodborne gastroenteritis. Recent studies have indicated a rise in fluoroquinolone-resistant (FQ-R) Campylobacter in cattle, where FQ is used to control bovine respiratory disease (BRD). To assess the effect of danofloxacin treatment on the development of FQ-resistance in C. jejuni, 30 commercial calves were divided into Group 1, Group 2, and Group 3 (n = 10), and were all inoculated orally with FQ-susceptible (FQ-S) C. jejuni; seven days later, Group 3 was challenged with transtracheal Mannheimia haemolytica, and one week later, Group 2 and Group 3 were injected subcutaneously with danofloxacin. Rectal feces were collected to determine relative percentages of FQ-R Campylobacter via culture. Before oral inoculation with C. jejuni, 87% of calves were naturally colonized by FQ-R C. jejuni. Two days after the inoculation, FQ-R C. jejuni decreased substantially in the majority of calves. Within 24 h of danofloxacin injection, almost all C. jejuni populations shifted to an FQ-R phenotype in both FQ-treated groups, which was only transitory, as FQ-S strains became predominant during later periods. Genotyping indicated that the spike seen in FQ-R C. jejuni populations following the injection was due mainly to enrichment of preexisting FQ-R C. jejuni, rather than development of de novo FQ resistance in susceptible strains. These results provide important insights into the dynamic changes of FQ-resistant Campylobacter in cattle in response to FQ treatment. Full article

(This article belongs to the Special Issue Epidemiology, Impact and Mitigation of Antimicrobial Resistance in Veterinary Medicine)

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13 pages, 406 KiB

Open AccessArticle

A Cross-Sectional Study of Veterinarians in Germany on the Impact of the TÄHAV Amendment 2018 on Antimicrobial Use and Development of Antimicrobial Resistance in Dogs and Cats

by Marianne Moerer, Roswitha Merle and Wolfgang Bäumer

Antibiotics 2022, 11(4), 484; https://doi.org/10.3390/antibiotics11040484 - 5 Apr 2022

Cited by 8 | Viewed by 1881

Abstract

To minimize the use of third- and fourth-generation cephalosporins and fluoroquinolones, the 2018 amendment to the regulations of veterinary pharmacies (TÄHAV) introduced legal restrictions in Germany. In an online survey among German veterinarians, we investigated the influence of these requirements on the use of antibiotics in the treatment of dogs and cats and the development of resistance rates. It was found that, on average, between 21% and 30% of daily treated dogs and cats received antimicrobial therapy. The TÄHAV amendment led to a less frequent use of highest priority critically important antimicrobials (HPCIA) in 79% (240/303) of respondents and less antimicrobial use in general in 36% (108/303). As a result of these legal changes, 63% (190/303) of participants requested antimicrobial susceptibility testing (AST) more frequently. Participants consulted ASTs particularly frequently for treatment of otitis externa with 63% (190/303), cystitis with 55% (168/303), wounds with 44% (132/303), and pyoderma with 29% (88/303). Veterinarians also noted an increased loss of antimicrobial efficacy, especially when treating these diseases. The results of our survey confirm that the TÄHAV amendment is having a positive impact on prudent antibiotic use, with participants performing more ASTs, using HPCIA less frequently, and choosing alternative antimicrobials for therapy. Full article

(This article belongs to the Special Issue Epidemiology, Impact and Mitigation of Antimicrobial Resistance in Veterinary Medicine)

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12 pages, 884 KiB

Open AccessArticle

Escherichia coli Isolated from Organic Laying Hens Reveal a High Level of Antimicrobial Resistance despite No Antimicrobial Treatments

by Claudia Hess, Salome Troxler, Delfina Jandreski-Cvetkovic, Angelika Zloch and Michael Hess

Antibiotics 2022, 11(4), 467; https://doi.org/10.3390/antibiotics11040467 - 30 Mar 2022

Cited by 9 | Viewed by 2069

Abstract

The present study investigated the resistance characteristics of E. coli isolates originating from 18 organic laying hen flocks. E. coli was isolated from different organs at three different time points, resulting in 209 E. coli isolates. The antibiotic susceptibility was determined by applying a microdilution assay. General, a high resistance rate was found. The antibiotic susceptibility was independent from the presence of pathological lesions, the isolation site, or the affiliation to a pathogenic serogroup. The majority of the isolates proved to be multi-drug-resistant (95.70%), of which 36.84% could be categorized as extensively drug-resistant. All isolates were resistant to oxacillin and tylosin. Resistance rates to amoxicillin (67.94%), cefoxitin (55.98%), ceftazidime (82.30%), colistin (73.68%), nalidixic acid (91.87%), streptomycin (42.58%), tetracycline (53.59%), and sulfamethoxazole (95.22%) were high. None of the isolates revealed pan-drug-resistance. A great heterogeneity of resistance profiles was found between isolates within a flock or from different organs of the same bird, even when isolates originated from the same organ. An increase in antimicrobial resistance was found to be correlated with the age of the birds. The fact, that no antibiotic treatment was applied except in two flocks, indicates that resistant bacteria circulating in the environment pose a threat to organic systems. Full article

(This article belongs to the Special Issue Epidemiology, Impact and Mitigation of Antimicrobial Resistance in Veterinary Medicine)

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19 pages, 7656 KiB

Open AccessArticle

Intestinal Exposure to Ceftiofur and Cefquinome after Intramuscular Treatment and the Impact of Ceftiofur on the Pig Fecal Microbiome and Resistome

by Sofie Rutjens, Nick Vereecke, Ward De Spiegelaere, Siska Croubels and Mathias Devreese

Antibiotics 2022, 11(3), 342; https://doi.org/10.3390/antibiotics11030342 - 4 Mar 2022

Cited by 2 | Viewed by 2410

Abstract

Optimization of antimicrobial treatment during a bacterial infection in livestock requires in-depth knowledge of the impact of antimicrobial therapy on the pathogen and commensal microbiota. Once administered antimicrobials and/or their metabolites are excreted either by the kidneys through urine and/or by the intestinal tract through feces, causing antimicrobial pressure and possibly the emergence of resistance in the gastro-intestinal tract. So far, the excretion of ceftiofur and cefquinome in the intestinal tract of pigs has not been described. The objective of this study was to investigate the excretion of ceftiofur and cefquinome in the different segments of the gut and feces after intramuscular administration. Therefore, 16 pigs were treated either with ceftiofur (n = 8) or cefquinome (n = 8), and feces were collected during the entire treatment period. The presence of ceftiofur and desfuroylceftiofuracetamide or cefquinome were quantified via liquid chromatography–tandem mass spectrometry. At the end of the treatment, pigs were euthanized, and samples from the duodenum, jejunum, ileum and cecum were analyzed. In feces, no active antimicrobial residues could be measured, except for one ceftiofur-treated pig. In the gut segments, the concentration of both antimicrobials increased from duodenum toward the ileum, with a maximum in the ileum (187.8 ± 101.7 ng·g⁻¹ ceftiofur-related residues, 57.8 ± 37.5 ng·g⁻¹ cefquinome) and sharply decreased in the cecum (below the limit of quantification for ceftiofur-related residues, 6.4 ± 4.2 ng·g⁻¹ cefquinome). Additionally, long-read Nanopore sequencing and targeted quantitative polymerase chain reaction (qPCR) were performed in an attempt to clarify the discrepancy in fecal excretion of ceftiofur-related residues between pigs. In general, there was an increase in Prevotella, Bacteroides and Faecalibacterium and a decrease in Escherichia and Clostridium after ceftiofur administration (q-value < 0.05). The sequencing and qPCR could not provide an explanation for the unexpected excretion of ceftiofur-related residues in one pig out of eight. Overall, this study provides valuable information on the gut excretion of parenteral administered ceftiofur and cefquinome. Full article

(This article belongs to the Special Issue Epidemiology, Impact and Mitigation of Antimicrobial Resistance in Veterinary Medicine)

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Review

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26 pages, 4316 KiB

Open AccessReview

Bovine Respiratory Disease: Conventional to Culture-Independent Approaches to Studying Antimicrobial Resistance in North America

by Sara Andrés-Lasheras, Murray Jelinski, Rahat Zaheer and Tim A. McAllister

Antibiotics 2022, 11(4), 487; https://doi.org/10.3390/antibiotics11040487 - 5 Apr 2022

Cited by 13 | Viewed by 3784

Abstract

Numerous antimicrobial resistance (AMR) surveillance studies have been conducted in North American feedlot cattle to investigate the major bacterial pathogens of the bovine respiratory disease (BRD) complex, specifically: Mannheimia haemolytica, Pasteurella multocida, Histophilus somni, and Mycoplasma bovis. While most bacterial isolates recovered from healthy cattle are susceptible to a repertoire of antimicrobials, multidrug resistance is common in isolates recovered from cattle suffering from BRD. Integrative and conjugative elements (ICE) have gained increasing notoriety in BRD-Pasteurellaceae as they appear to play a key role in the concentration and dissemination of antimicrobial resistant genes. Likewise, low macrolide susceptibility has been described in feedlot isolates of M. bovis. Horizontal gene transfer has also been implicated in the spread of AMR within mycoplasmas, and in-vitro experiments have shown that exposure to antimicrobials can generate high levels of resistance in mycoplasmas via a single conjugative event. Consequently, antimicrobial use (AMU) could be accelerating AMR horizontal transfer within all members of the bacterial BRD complex. While metagenomics has been applied to the study of AMR in the microbiota of the respiratory tract, the potential role of the respiratory tract microbiome as an AMR reservoir remains uncertain. Current and prospective molecular tools to survey and characterize AMR need to be adapted as point-of-care technologies to enhance prudent AMU in the beef industry. Full article

(This article belongs to the Special Issue Epidemiology, Impact and Mitigation of Antimicrobial Resistance in Veterinary Medicine)

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