Original Scientific Article
Echocardiographic and hematological changes in dogs naturally infected with Ehrlichia spp.
Zeynep Ustaer ,
Tahir Özalp ,
Songül Erdogan ,
Kerem Ural ,
Hasan Erdogan *

Mac Vet Rev 2025; 48 (2): i - x

10.2478/macvetrev-2025-0027

Received: 01 November 2024

Received in revised form: 13 June 2025

Accepted: 27 June 2025

Available Online First: 31 July 2025

Published on: 15 October 2025

Correspondence: Hasan Erdogan, hasaner.09@gmail.com
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Abstract

This study aimed to assess the severity of anemia, associated parameters, and their impact on cardiac function in dogs naturally infected with Ehrlichia canis (E. canis), a zoonotic pathogen primarily transmitted by the brown dog tick.Forty-seven dogs, comprising 38 infected and 9 healthy controls, were classified into non-anemic (n=12), mildly mild(n=9), moderately (n=11), severely (n=4), and very severely anemic (n=2), groups. Hematological and echocardiographicassessments were performed, along with separate measurements of cardiac biomarkers (e.g., cardiac troponin I [cTnI]) andiron metabolism biomarkers (e.g., serum iron, total iron-binding capacity [TIBC], and transferrin saturation). Hematologicalanalysis revealed a significant reduction in hematocrit (17.11±1.34%), hemoglobin (5.22±0.88 g/dL), and platelet counts(38.25±22.62×10⁹/L) in severely anemic dogs compared to other groups. Echocardiographic findings demonstrated increasedinterventricular septal thickness during diastole (1.16±0.60 cm) and systole (1.38±0.10 cm) in moderately anemic dogs, indicatingcompensatory adaptations. Dogs with severe anemia exhibited elevated left ventricular end-diastolic (3.56±0.54 cm) andend-systolic dimensions (1.71±0.22 cm) in comparison to control dogs (p<0.05). Fractional shortening (53.83±7.71%) andejection fraction (77.58±8.19%) were diminished among the severely anemic group, denoting altered cardiac function.Elevated cardiac troponin I (cTnI) levels (up to 0.29±0.22 ng/mL) were noted in a limited number of cases, suggesting thatmyocardial injury was not widespread. This study demonstrated that anemia severity significantly influences myocardialand hematological parameters in E. canis-infected dogs, with evidence indicating compensatory cardiac remodeling inresponse to chronic anemia. Further research utilizing advanced diagnostic techniques is recommended to better understanddisease progression and associated complications.

Keywords: Ehrlichiosis, dogs, haematology, biochemistry, echocardiography

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Copyright

© 2025 Ustaer Z. This is an open-access article published under the terms of the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Conflict of Interest Statement

The authors have declared that no competing interests exist.

Citation Information

Macedonian Veterinary Review. Volume 48, Issue 2, Pages i-x, e-ISSN 1857-7415, p-ISSN 1409-7621, DOI: https://doi.org/10.2478/macvetrev-2025-0027 

The all content of the Macedonian Veterinary Review, except where otherwise noted, is licensed under a Creative Commons Attribution License.