Related Experiment Video

Updated: Aug 21, 2026

Antimicrobial Synergy Testing by the Inkjet Printer-assisted Automated Checkerboard Array and the Manual Time-kill Method
12:03

Antimicrobial Synergy Testing by the Inkjet Printer-assisted Automated Checkerboard Array and the Manual Time-kill Method

Published on: April 18, 2019

Minimum inhibitory concentrations of some antimicrobial drugs against bacteria causing uterine infections in cattle

I M Sheldon1, M Bushnell, J Montgomery

  • 1Department of Veterinary Clinical Sciences, Royal Veterinary College, Hawkshead Lane, Hatfield AL9 7TA.

The Veterinary Record
|October 27, 2004
PubMed

Insights

Cefquinome and enrofloxacin show the most promise for treating uterine infections in animals caused by Escherichia coli. Cephalosporins are effective against Arcanobacterium pyogenes and anaerobic bacteria.

Area of Science:

  • Veterinary Medicine
  • Microbiology
  • Pharmacology

Background:

  • Uterine infections in animals are often caused by Escherichia coli, Arcanobacterium pyogenes, Fusobacterium necrophorum, and Prevotella melaninogenicus.
  • Identifying effective antibiotics is crucial for treating metritis and endometritis.

Purpose of the Study:

  • To determine the minimum inhibitory concentrations (MICs) of several candidate antibiotics against key bacteria involved in bovine uterine infections.
  • To compare the efficacy of oxytetracycline, cephapirin, cephapirin/mecillinam, cefquinome, ceftiofur, and enrofloxacin.

Main Methods:

  • Agar dilution method was employed to determine MICs.
  • Bacteria were isolated from animals diagnosed with clinical metritis and/or endometritis.

Main Results:

  • Cefquinome and enrofloxacin demonstrated the lowest MIC90 and MIC50 values for E. coli (< 0.06 microg/ml).
  • Oxytetracycline exhibited the highest MIC50 for A. pyogenes (16 microg/ml), while cephalosporins were highly effective (< 0.06 microg/ml).
  • Cephalosporins showed low MIC values (≤ 0.06 microg/ml) against anaerobic bacteria, whereas enrofloxacin and oxytetracycline had higher MIC50 values.

Conclusions:

  • Cefquinome and enrofloxacin are potent against E. coli associated with uterine infections.
  • Cephalosporins are effective against A. pyogenes and anaerobic bacteria commonly found in uterine infections.

More Related Videos

A Method to Assess Bacteriocin Effects on the Gut Microbiota of Mice07:54

A Method to Assess Bacteriocin Effects on the Gut Microbiota of Mice

Published on: July 25, 2017

Related Concept Videos

Clinical Significance of Antibiotic Resistance01:25

Clinical Significance of Antibiotic Resistance

Methicillin-resistant Staphylococcus aureus (MRSA) presents a critical public health threat, arising from its capacity to resist β-lactam antibiotics due to acquisition of the mecA gene within the staphylococcal cassette chromosome mec (SCCmec). This gene encodes penicillin-binding protein 2a (PBP2a), which impairs binding efficacy of methicillin and other β-lactams. MRSA has evolved into distinct clonal lineages impacting humans and animals alike, reinforcing its significance within the One...
Inhibitors of Bacterial Protein Synthesis01:25

Inhibitors of Bacterial Protein Synthesis

Aminoglycosides constitute a highly potent class of bactericidal antibiotics that exert their antimicrobial effects by targeting the bacterial ribosome, specifically disrupting protein synthesis. These polycationic molecules consist of amino-modified sugars linked via glycosidic bonds to an aminocyclitol core such as 2-deoxystreptamine or streptamine. Their strong positive charges facilitate tight binding to the negatively charged phosphate backbone of ribosomal RNA (rRNA), primarily at the 16S...
Combined Effects of Drugs: Synergism01:27

Combined Effects of Drugs: Synergism

Synergism is a useful mechanism where combining two or more drugs is more effective than each constituent used alone. Such combinations are also called supra-additive interactions. The drugs collectively enhance the final therapeutic effect by acting on different targets. Another advantage is that the low dose of each constituent drug is sufficient to achieve the desired effect. This helps reduce the duration of therapy and lower the adverse effects of these drugs.
Such synergistic combinations...
Urine Studies II: Urine Culture and Sensitivity Test01:26

Urine Studies II: Urine Culture and Sensitivity Test

A urine culture and sensitivity test is a diagnostic procedure used to identify urinary tract bacterial infections and determine the most effective antibiotics for treatment. This test is generally preferred when a patient shows manifestations of a urinary tract infection, such as frequent or painful urination, cloudy or foul-smelling urine, or lower abdominal pain.Purpose of the TestThe primary goals of a urine culture and sensitivity test are to:Determine the specific bacteria causing the...
Antimicrobial Effectiveness01:28

Antimicrobial Effectiveness

The effectiveness of antimicrobial agents depends on various factors influencing their ability to eliminate microbial populations. Larger microbial populations require more time for complete eradication, emphasizing the importance of population size analysis when evaluating antimicrobial efficacy.Microbial resistance to antimicrobial agents varies significantly. Highly resilient microorganisms include endospores, gram-negative bacteria, and non-enveloped viruses, while prions are exceptionally...
Inhibitors of Gram-positive Cell Wall Synthesis01:23

Inhibitors of Gram-positive Cell Wall Synthesis

Bacterial cell walls are typically rigid structures composed mainly of peptidoglycan, a mesh-like polymer that provides mechanical strength and maintains cell shape. The synthesis of peptidoglycan is a crucial process in bacterial growth and serves as a primary target for many antibiotics.Mechanism of Action of Beta-Lactam AntibioticsBeta-lactam antibiotics, such as penicillin, inhibit peptidoglycan synthesis in actively growing cells. These antibiotics share a characteristic four-membered...