Susceptibility of equine bacterial isolates to antimicrobial agents.
- Journal Article
- Research Support
- Non-U.S. Gov't
Summary
This research study investigates the vulnerability of common bacterial pathogens found in horses to different antibiotics. Results for each antibiotic are given as effective concentrations against the bacteria.
Study Overview
This study aims to understand the susceptibility to antibiotics of a variety of bacterial pathogens commonly isolated from horses. These pathogens are regularly encountered in equine medicine and knowing their antibiotic susceptibility patterns is essential for effective treatment.
Methods
Researchers used the agar-plate dilution method, which is a standard technique to determine the minimum inhibitory concentration (MIC) of antibiotics needed to inhibit the growth of the bacteria. The lower the MIC, the more effective the antibiotic is against the bacteria.
Bacterial Isolates
The study profiles several aerobic bacterial pathogens, including both gram-positive and gram-negative strains such as:
- Corynebacterium (Rhodococcus) equi
- Corynebacterium pseudotuberculosis
- Coagulase positive Staphylococcus species
- Streptococcus equi
- Streptococcus zooepidemicus
- Actinobacillus species
- Enterobacter cloacae
- Escherichia coli
- Klebsiella pneumoniae
- Pseudomonas aeruginosa
- Salmonella species
Antibiotic Susceptibility
The researchers tested susceptibility to 14 different antibiotics, providing the in vitro susceptibility levels for each antibiotic. The lower the concentration required, the greater is the bacteria’s susceptibility to that antibiotic. The antibiotics and their effective concentrations are as follows:
- Amikacin (≤ 4.0 µg/ml)
- Ampicillin, Amoxicillin, Erythromycin, Penicillin, Tetracycline (≤ 1.0 µg/ml)
- Cefadroxil, Chloramphenicol (≤ 8.0 µg/ml)
- Gentamicin (≤ 2.0 µg/ml)
- Kanamycin (≤ 4.0 µg/ml)
- Sulfadimethoxine, Sulfadiazine (≤ 10.0 µg/ml)
- Ormetoprim/Sulfadimethoxine, Trimethoprim/Sulfadiazine (≤ 0.5/9.5 µg/ml)
The study provides detailed antimicrobial resistance data valuable for treating equine diseases caused by these pathogens. It helps veterinarians prescribe more effective antibiotics for treating infections in horses.
Cite This Article
Publication
Researcher Affiliations
MeSH Terms
- Aerobiosis
- Animals
- Anti-Bacterial Agents / pharmacology
- Drug Resistance, Microbial
- Gram-Negative Aerobic Bacteria / drug effects
- Gram-Positive Bacteria / drug effects
- Horse Diseases / microbiology
- Horses
- Microbial Sensitivity Tests
- Species Specificity
Citations
This article has been cited 8 times.- Pezzanite L, Chow L, Hendrickson D, Gustafson DL, Russell Moore A, Stoneback J, Griffenhagen GM, Piquini G, Phillips J, Lunghofer P, Dow S, Goodrich LR. Evaluation of Intra-Articular Amikacin Administration in an Equine Non-inflammatory Joint Model to Identify Effective Bactericidal Concentrations While Minimizing Cytotoxicity. Front Vet Sci 2021;8:676774.
- Dahan R, Oreff GL, Tatz AJ, Raz T, Britzi M, Kelmer G. Pharmacokinetics of regional limb perfusion using a combination of amikacin and penicillin in standing horses. Can Vet J 2019 Mar;60(3):294-299.
- Feßler AT, Schwarz S. Antimicrobial Resistance in Corynebacterium spp., Arcanobacterium spp., and Trueperella pyogenes. Microbiol Spectr 2017 Dec;5(6).
- Rhodes DM, Magdesian KG, Byrne BA, Kass PH, Edman J, Spier SJ. Minimum inhibitory concentrations of equine Corynebacterium pseudotuberculosis isolates (1996-2012). J Vet Intern Med 2015 Jan;29(1):327-32.
- Lavoie JP, Couture L, Higgins R, Laverty S. Aerobic bacterial isolates in horses in a university hospital, 1986-1988. Can Vet J 1991 May;32(5):292-4.
- Jacks SS, Giguère S, Nguyen A. In vitro susceptibilities of Rhodococcus equi and other common equine pathogens to azithromycin, clarithromycin, and 20 other antimicrobials. Antimicrob Agents Chemother 2003 May;47(5):1742-5.
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- Green SL, Mayhew IG, Brown MP, Gronwall RR, Montieth G. Concentrations of trimethoprim and sulfamethoxazole in cerebrospinal fluid and serum in mares with and without a dimethyl sulfoxide pretreatment. Can J Vet Res 1990 Apr;54(2):215-22.
