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Advances in wound care2019; 8(10); 487-498; doi: 10.1089/wound.2018.0901

An Equine Wound Model to Study Effects of Bacterial Aggregates on Wound Healing.

Abstract: Objective: Relevant animal models to study effects of bacterial aggregates on wound healing are lacking. We aimed at establishing an equine wound model with bacterial aggregates to investigate the impact of bacterial inoculation on normal (thorax) and impaired (limb) wound healing. Approach: Wounds were created on three limbs and both thorax sides of six horses. Twelve out of 20 wounds per horse were inoculated with 104 Staphylococcus aureus and 105 Pseudomonas aeruginosa on day 4. Healing was monitored until day 27 by clinical assessment, including wound scoring, surface pH measurements, and digital photography for area determination. Biopsies were used for bacterial culture and for peptide nucleic acid fluorescence in situ hybridization to detect bacterial aggregates. Results: Inoculated limb wounds healed slower than noninoculated limb wounds from day 10 onward (p < 0.0001). Inoculated and noninoculated thorax wounds healed equally well and faster than limb wounds. The odds ratio of detecting bacterial aggregates in inoculated limb wounds was 7.1 (2.4-21.0, p = 0.0086) compared with noninoculated limb wounds and 36.2 (3.8-348, p = 0.0018) compared with thorax wounds. Innovation: This equine wound model with bacterial aggregates might be superior to other animal wound models, as both normal and impaired healing can be studied simultaneously. In this model, many aspects of wound healing, including novel treatments, may be studied. Conclusions: The impaired healing observed in inoculated limb wounds may be related to the persistent bacterial aggregates. Both in capability of clearing inoculated bacteria from the wounds and in healing pattern, thorax wounds were superior to limb wounds.
Publication Date: 2019-08-21 PubMed ID: 31456906PubMed Central: PMC6709944DOI: 10.1089/wound.2018.0901Google Scholar: Lookup
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  • Journal Article

Summary

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The study presents a new equine wound model that enables researchers to observe the effects of bacterial aggregates on wound healing under both normal and impaired conditions. Notably, it was observed that wounds on the limbs healed slower when inoculated with bacteria, which might be attributed to persistent bacterial aggregates.

Creating the Model

  • The researchers aimed to create an equine wound model where the impact of bacterial inoculation on normal (thorax or chest area) and impaired (limb) wound healing could be studied.
  • Wounds were made on both thorax sides and on three limbs of six horses. Out of 20 wounds, 12 were inoculated with bacteria on the fourth day.

Observation and Assessment

  • Healing of the wounds was monitored till the 27th day. The observation included clinical assessment, wound scoring, measuring surface pH, and digital photography for determining the wound area.
  • Wound biopsies were conducted to culture bacteria and to detect bacterial aggregates using peptide nucleic acid fluorescence hybridization.

Findings of the Study

  • Inoculated wounds on the limbs healed slower than the non-inoculated wounds starting from the tenth day. On the other hand, both inoculated and non-inoculated thorax wounds healed relatively faster.
  • The likelihood of finding bacterial aggregates in inoculated limb wounds was 7.1 times higher compared to non-inoculated limb wounds, and 36.2 times higher compared to thorax wounds.

Significance of the Findings

  • These findings imply that the equine wound model might be superior to other animal models for studying wound healing as it allows simultaneous studies on both normal and impaired healing.
  • The results also suggest that the slowed healing observed in inoculated limb wounds was probably due to the presence of persistent bacterial aggregates. In comparison, thorax wounds exhibited superior healing patterns and ability to clear inoculated bacteria.

Cite This Article

APA
Jørgensen E, Bay L, Skovgaard LT, Bjarnsholt T, Jacobsen S. (2019). An Equine Wound Model to Study Effects of Bacterial Aggregates on Wound Healing. Adv Wound Care (New Rochelle), 8(10), 487-498. https://doi.org/10.1089/wound.2018.0901

Publication

ISSN: 2162-1918
NlmUniqueID: 101590593
Country: United States
Language: English
Volume: 8
Issue: 10
Pages: 487-498

Researcher Affiliations

Jørgensen, Elin
  • Department of Veterinary Clinical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Taastrup, Denmark.
Bay, Lene
  • Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen N, Denmark.
Skovgaard, Lene T
  • Section of Biostatistics, Department of Public Health, University of Copenhagen, Copenhagen K, Denmark.
Bjarnsholt, Thomas
  • Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen N, Denmark.
  • Department of Clinical Microbiology, Rigshospitalet, Copenhagen Ø, Denmark.
Jacobsen, Stine
  • Department of Veterinary Clinical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Taastrup, Denmark.

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Citations

This article has been cited 5 times.
  1. Repciuc CC, Oros NV, Mureșan ȘMC, Sevastre B, Joaquim JGF, Oana LI. Efficacy of Ozone Bagging Therapy in Equine Chronic Distal Limb Wounds: Clinical Evaluation of Eight Cases. Vet Sci 2025 Dec 23;13(1).
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  4. Jørgensen E, Bjarnsholt T, Jacobsen S. Biofilm and Equine Limb Wounds. Animals (Basel) 2021 Sep 27;11(10).
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