Case Report

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

Sean M. Miller
Journal of the South African Veterinary Association | Vol 91 | a1983 | DOI: | © 2020 Sean M. Miller | This work is licensed under CC Attribution 4.0
Submitted: 31 May 2019 | Published: 07 July 2020

About the author(s)

Sean M. Miller, Summerveld Equine Hospital, Durban, South Africa

Share this article

Bookmark and Share


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.


equine, tick, Otobius megnini, veterinary, parasitology, acarology


Total abstract views: 1609
Total article views: 1019

Crossref Citations

No related citations found.