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Journal of the South African Veterinary Association2020; 91; e1-e6; doi: 10.4102/jsava.v91i0.1983

Putative Otobius megnini-associated clinical signs in horses in South Africa (2012-2018).

Abstract: Otobius megnini has been associated with certain clinical conditions in horses in both California and Mexico. A number of cases similar to those described previously have been identified by the author in South Africa. This case report summarises these cases to demonstrate that the clinical condition occurs readily in South Africa and may be increasing in occurrence. The disease has minimal coverage in the literature making it more likely that a veterinarian, unfamiliar with the disease, will miss the diagnosis. The author would like to make veterinarians aware of this as a potential differential diagnosis. This study is a retrospective review of clinical data. Clinical records of patients with similar clinical signs and treatment were reviewed and grouped together as relevant cases for this case report. Ten cases of O. megnini associated neuromuscular dysfunction are reported, suggesting a link between the occurrence of the tick and the clinical condition. Clinical signs include third eyelid prolapse, localised muscle fasciculations, elevated heart rate and limb stamping. Serum chemistry changes commonly show increased aspartate aminotransferase and creatine kinase enzymes activities. The occurrence of the ticks within South Africa and the increasing number of cases presented demonstrate the need for more investigation into the pathophysiology of this condition.
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Publication Date: 2020-07-07 PubMed ID: 32633987PubMed Central: PMC7433235DOI: 10.4102/jsava.v91i0.1983Google 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.

The research paper discusses a study that establishes a potential link between the tick Otobius megnini and certain neurological conditions in horses in South Africa, a correlation previously noticed in California and Mexico. The study found ten cases of O. megnini-related neuromuscular dysfunction, highlighting the need for additional investigation.

Introduction and Background

  • The tick Otobius megnini has been associated with certain specific clinical conditions in horses in both California and Mexico. The author of this study observed similar cases in South Africa, raising the possibility that the clinical condition occurs regularly and might be on the rise in the region.
  • Given that the disease has only faint coverage in the existing literature, the author points out the likelihood of veterinarians unfamiliar with the disease missing the diagnosis.

Research Methodology

  • This study is a retrospective review of clinical data. It involved examining past clinical records of patients that showed similar clinical signs and received similar treatments.
  • The records were then grouped together, culminating in ten cases that were relevant for the report, all associated with O. megnini and neuromuscular dysfunction.

Findings and Observations

  • The study reported a link between the occurrence of the tick and the clinical condition. Clinical signs accompanying this condition include third eyelid prolapse, localised muscle fasciculations, an increase in heart rate, and limb stamping.
  • Serum chemistry changes in affected horses commonly showed elevated aspartate aminotransferase and creatine kinase enzyme activities, pointing towards a potential indicator of the disease.

Conclusions and Recommendations

  • The research concluded that the presence of O. megnini ticks within South Africa and the increasing number of cases indicate a need for further investigation into the pathophysiology of this condition.
  • The author emphasizes making veterinarians aware of this potential differential diagnosis to ensure that they can accurately diagnose and treat the condition in the future.

Cite This Article

APA
Miller SM. (2020). Putative Otobius megnini-associated clinical signs in horses in South Africa (2012-2018). J S Afr Vet Assoc, 91, e1-e6. https://doi.org/10.4102/jsava.v91i0.1983

Publication

Journal of the South African Veterinary Association
ISSN: 2224-9435
NlmUniqueID: 7503122
Country: South Africa
Language: English
Volume: 91
Pages: e1-e6
PII: 1983

Researcher Affiliations

Miller, Sean M
  • Summerveld Equine Hospital, Durban. sean@drummondtor.co.za.

MeSH Terms

  • Animals
  • Argasidae / physiology
  • Diagnosis, Differential
  • Female
  • Horse Diseases / diagnosis
  • Horse Diseases / parasitology
  • Horses
  • Male
  • Retrospective Studies
  • South Africa
  • Tick Infestations / diagnosis
  • Tick Infestations / parasitology
  • Tick Infestations / veterinary

Conflict of Interest Statement

The author declares that he has no financial or personal relationships that may have inappropriately influenced him in writing this article.

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