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Veterinary ophthalmology2025; doi: 10.1111/vop.70044

Pantoea agglomerans in Equine Ulcerative Keratitis: Prevalence and Comparative Efficacy of Four Topical Antiseptics.

Abstract: No abstract available
© 2025 The Author(s). Veterinary Ophthalmology published by Wiley Periodicals LLC on behalf of American College of Veterinary Ophthalmologists.
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Publication Date: 2025-06-25 PubMed ID: 4055744740557447DOI: 10.1111/vop.70044Google Scholar: Lookup
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

This research article investigates the effectiveness of four different antiseptics on equine ulcerative keratitis caused by the Pantoea agglomerans bacteria. The results suggest all tested antiseptics were successful in neutralizing the bacteria, with three of them working rapidly and the fourth one needing higher concentrations and more time.

Objective of the Study

  • The purpose of the study was to identify the minimal bactericidal concentration (MBC), which is the lowest concentration of an antibacterial agent required to kill a particular bacterium, and the effective contact time of four topical antiseptics against Pantoea agglomerans. This bacterium is often found in horses with ulcerative keratitis, an infection of the cornea that can cause pain and sometimes blindness.

Methodology

  • During a 17-month sampling period, the researchers collected clinical isolates from horses diagnosed with ulcerative keratitis.
  • The most commonly isolated strain was Pantoea agglomerans, which was used for in vitro (outside of the living organism) analysis.
  • The MBCs of polyhexanide, povidone-iodine, hypochlorous acid, and N-acetylcysteine were determined by testing each antiseptic, in triplicate, on a series of diluted bacteria isolates.
  • The researchers also undertook a study to evaluate the necessary contact time for each antiseptic to effectively kill the bacteria at a level above the intended therapeutic concentration. The time durations tested ranged from 15 seconds to 5 minutes.

Results

  • The results of the study revealed that the MBCs of polyhexanide, povidone-iodine (PVP-I), hypochlorous acid (HOCl), and N-acetylcysteine (NAC) were respectively 3.2 ppm, 16 ppm, 0.8 ppm, and 3200 ppm.
  • Polyhexanide, PVP-I, and HOCl were effective in killing the bacteria within 15 seconds. NAC, however, required a concentration of 6400 ppm and a timespan of 1-2 minutes to achieve its bactericidal effects.

Conclusion

  • Overall, all four antiseptics demonstrated effectiveness against Pantoea agglomerans. Three of them gained rapid bactericidal efficacy, whereas NAC required both a higher concentration and longer exposure time.
  • The findings support the potential use of these antiseptics as viable substitutes to antibiotics in the treatment of equine ulcerative keratitis. This aligns with the One Health approach, which aims to reduce the use of antibiotics.

Cite This Article

APA
(2025). Pantoea agglomerans in Equine Ulcerative Keratitis: Prevalence and Comparative Efficacy of Four Topical Antiseptics. Vet Ophthalmol. https://doi.org/10.1111/vop.70044

Publication

Veterinary ophthalmology
ISSN: 1463-5224
NlmUniqueID: 100887377
Country: England
Language: English

Researcher Affiliations

References

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