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Journal of the American Veterinary Medical Association1987; 190(4); 445-448;

Equine ehrlichiosis in northern California: 49 cases (1968-1981).

Abstract: Case records of horses with equine ehrlichiosis (Ehrlichia equi) at the University of California Veterinary Medical Teaching Hospital and Ackerman Creek Large Animal Clinic were analyzed for evaluation of clinical signs, time of onset, hematologic values, response to treatment, and recovery. Equine ehrlichiosis was found to be seasonal in horses in the foothills of northern California, with higher incidence than reported previously. The horses developed fever, anorexia, depression, limb edema, icterus, and ataxia. Hematologic changes were leukopenia, thrombocytopenia, icterus, anemia, and inclusion bodies in the neutrophils and eosinophils. Diagnosis was made by observing the characteristic inclusion bodies, using a standard Wright's stain. Mortality was low, although complications of opportunistic secondary infection and injury due to ataxia did develop. Treatment with tetracycline resulted in prompt clinical improvement within 24 hours. Chronic cases were not detected. Equine ehrlichiosis should be differentiated from diseases with similar clinical signs including encephalitis, liver disease, purpura hemorrhagica, equine infectious anemia, and equine viral arteritis.
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Publication Date: 1987-02-15 PubMed ID: 3558086
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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 analyzes case records of equine ehrlichiosis in northern California, investigating its symptoms, onset, hematology, treatment response, and recovery. The data suggests that equine ehrlichiosis is a seasonal disease with a higher incidence than previously reported.

Study Overview and Objective

The study primarily focuses on examining the clinical signs, time of onset, hematological alterations, treatment responses, and recovery processes in cases of equine ehrlichiosis, a bacterial infection affecting horses. It leverages case records from the University of California Veterinary Medical Teaching Hospital and Ackerman Creek Large Animal Clinic.

Disease Characteristics

  • The study found that equine ehrlichiosis primarily exhibits seasonal patterns in northern California’s foothills, and its incidence is higher than what was previously reported.
  • Major symptoms of the infection in horses include fever, lack of appetite (anorexia), depression, swelling of the limbs (limb edema), yellowing of the skin, eyes, and gums (icterus), and loss of coordination (ataxia).
  • Key hematological changes mirrored white blood cell reduction (leukopenia), platelet decrease (thrombocytopenia), icterus, anemia, and the presence of inclusion bodies in neutrophils and eosinophils, types of white blood cells.

Diagnosis and Treatment

  • Diagnosis was primarily obtained by observing the characteristic inclusion bodies using a standard Wright’s stain technique.
  • The mortality rate among the affected horses was relatively low. However, complications that included secondary infections due to opportunist pathogens and injuries caused by a loss of coordination were observed.
  • The study found that the administration of the antibiotic tetracycline resulted in substantial clinical improvements within 24 hours. Interestingly, chronic cases were not detected throughout the course of this research.

Differential Diagnostics

The paper concludes by emphasizing the necessity to distinguish equine ehrlichiosis from other diseases that present similar clinical signs. These include encephalitis, liver disease, purpura hemorrhagica, equine infectious anemia, and equine viral arteritis.

Cite This Article

APA
Madigan JE, Gribble D. (1987). Equine ehrlichiosis in northern California: 49 cases (1968-1981). J Am Vet Med Assoc, 190(4), 445-448.

Publication

Journal of the American Veterinary Medical Association
ISSN: 0003-1488
NlmUniqueID: 7503067
Country: United States
Language: English
Volume: 190
Issue: 4
Pages: 445-448

Researcher Affiliations

Madigan, J E
    Gribble, D

      MeSH Terms

      • Animals
      • California
      • Ehrlichia / ultrastructure
      • Horse Diseases / epidemiology
      • Horses
      • Microscopy, Electron
      • Retrospective Studies
      • Rickettsiaceae Infections / epidemiology
      • Rickettsiaceae Infections / veterinary
      • Seasons

      Citations

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