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Home / Equine Research Bank / Vet Ophthalmol / Conjunctival bacterial and fungal flora in healthy horses in...
Veterinary ophthalmology2011; 14(3); 195-199; doi: 10.1111/j.1463-5224.2010.00867.x

Conjunctival bacterial and fungal flora in healthy horses in the UK.

Abstract: To describe the bacterial and fungal flora of the normal conjunctiva of horses in the UK; to determine the effect of horse age, sex, geographic location, and housing on this flora; and to determine the most appropriate antimicrobial drug(s) for prophylactic treatment of corneal ulcers. Methods: A total of 60 adult healthy horses were studied. Methods: Swabs of the conjunctiva were obtained from 60 horses housed in two locations within the UK. Specimens were cultured for aerobic bacteria and fungi, and sensitivity against six ophthalmic antimicrobials assessed. The effect of age, sex, location and housing on the frequency of microbial isolation was evaluated. Results: Fifty-four bacterial isolates, representing thirteen genera of bacteria were cultured from 31 (52%) horses. The most frequently isolated bacterial species was Acinetobacter sp (17/32 horses). The majority of isolates (28/54: 52%) were gram-positive. Three genera of fungi (Mucor, Absidia and Aspergillus spp) were isolated from eight (13%) horses. There was no significant effect of geographic location, sex, age or housing on frequency of microbial isolation. Horses from which gram-negative bacteria were isolated were significantly older than horses from which gram-positive bacteria were isolated. High efficacy (greater than 90% of isolates sensitive in vitro) was displayed by chloramphenicol, gentamicin and tetracycline. Conclusions: The microbial species isolated are comparable with studies performed in other countries, although the frequency of Acinetobacter isolation was higher which may reflect a geographic difference. The topical antimicrobials gentamicin and chloramphenicol are appropriate first line antimicrobials for empirical treatment of corneal ulcers in the UK.
© 2011 American College of Veterinary Ophthalmologists.
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Publication Date: 2011-04-28 PubMed ID: 21521444DOI: 10.1111/j.1463-5224.2010.00867.xGoogle Scholar: Lookup
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  • Journal Article

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 study examines the bacterial and fungal flora of healthy horse eyes in the UK to understand the effect of various factors like age, sex, geography, and housing, and to prescribe suitable antimicrobial drugs for treating corneal ulcers.

Research Methodology

  • The study was conducted on a group of 60 healthy adult horses from two different locations in the UK.
  • Swabs were taken from the conjunctiva, the membrane that covers the front of the eye and lines the inside of the eyelids, of these horses.
  • These samples were then cultured for aerobic bacteria and fungi, which then helped in identifying possible organisms present.
  • The researchers also assessed sensitivity against six ophthalmic antimicrobials, which are drugs used to treat eye infections.
  • The research analyzed the influence of factors such as age, sex, location, and housing on the frequency of microbial isolation.

Results of the Study

  • Fifty-four bacterial isolates, representing thirteen different genera of bacteria were cultured from 31 horses, making up 52% of the total subjects.
  • The most frequently isolated bacterial species was Acinetobacter sp, which was found in roughly half of the horses.
  • On further classification, 52% of these bacteria were found to be gram-positive.
  • Three genera of fungi – Mucor, Absidia and Aspergillus spp – were identified from 13% of the horses.
  • The study reported no significant impact of geographic location, sex, age or housing on the frequency of microbial isolation.
  • Horses from which gram-negative bacteria were isolated were found to be significantly older than those from which gram-positive bacteria were isolated.
  • Three drugs – chloramphenicol, gentamicin and tetracycline – displayed high efficacy, with more than 90% of isolates being sensitive to them in vitro.

Study Conclusions

  • The microbial species isolated from this study were found to be similar to those reported in studies conducted in other countries.
  • The higher frequency of Acinetobacter isolation could possibly indicate a geographic difference in bacterial flora of horse conjunctiva.
  • The study also concluded that the topical antimicrobials gentamicin and chloramphenicol are effective as the first line of treatment for corneal ulcers in horses in the UK.

Cite This Article

APA
Johns IC, Baxter K, Booler H, Hicks C, Menzies-Gow N. (2011). Conjunctival bacterial and fungal flora in healthy horses in the UK. Vet Ophthalmol, 14(3), 195-199. https://doi.org/10.1111/j.1463-5224.2010.00867.x

Publication

Veterinary ophthalmology
ISSN: 1463-5224
NlmUniqueID: 100887377
Country: England
Language: English
Volume: 14
Issue: 3
Pages: 195-199

Researcher Affiliations

Johns, Imogen C
  • Equine Referral Hospital, Veterinary Clinical Science, Royal Veterinary College, Hawkshead Lane, North Mymms, Herts AL9 7TA, UK. ijohns@rvc.ac.uk
Baxter, Katherine
    Booler, Helen
      Hicks, Charlotte
        Menzies-Gow, Nicola

          MeSH Terms

          • Aging
          • Animals
          • Anti-Bacterial Agents / pharmacology
          • Bacteria / classification
          • Bacteria / drug effects
          • Bacteria / isolation & purification
          • Conjunctiva / microbiology
          • Drug Resistance, Bacterial
          • Female
          • Fungi / classification
          • Fungi / isolation & purification
          • Horses / microbiology
          • Housing, Animal
          • Male
          • Sex Characteristics
          • United Kingdom

          Citations

          This article has been cited 24 times.
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