Clinical occurrence of trypanosomiasis in Arabian horses from Ahvaz.
Abstract: Trypanosoma evansi (T. evansi) is a hemoprotozoan parasite affecting camels and equids, such as horses, mules, and donkeys, and is known to cause surra disease in these animals. Despite the worldwide distribution of T. evansi infections in equids, surra has not been reported in Arabian horses in Khuzestan Province for over 60 years. In September 2018, a 7-year-old Arabian mare was referred from a 10-horse farm in the suburbs of Ahvaz City. The mare presented with a history of weight loss, poor appetite, and proximity to a camel herd. Physical examination revealed a poor body condition score (BCS ≤ 3/9), pale conjunctival and oral mucosal membranes, dehydration, tachycardia, and fever. Other horses in the herd also exhibited gradual weight loss and hyporexia, with two fatalities reported. A hematologic examination of the referred mare showed leukopenia, severe anemia, and thrombocytopenia. Microscopic examination of a whole blood smear confirmed severe infection with Trypanosoma. PCR assessment of a blood sample further confirmed the infection with T. evansi. The referred mare and seven nonreferred patients from the herd received treatment with diminazene diaceturate (5 mg/kg, a single dose) and penicillin for 4 days. Unfortunately, the referred mare died despite the treatment, while the remaining nonreferred horses recovered. This report marks the first molecular diagnosis of surra in an Arabian horse in Khuzestan Province, highlighting the need for further investigation into surra as a re-emerging disease in this significant population of Arabian horses in the region.
© 2025 American Society for Veterinary Clinical Pathology.
Publication Date: 2025-06-03 PubMed ID: 40462454DOI: 10.1111/vcp.70003Google Scholar: Lookup
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Summary
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The research article details a case of surra disease caused by the parasite T. evansi, popping up for the first time in 60 years among Arabian horses in the Khuzestan Province. The diagnosis was confirmed through PCR and notified as a re-emerging disease in this particular horse population.
Background of the Study
- The study was triggered by the occurrence of Trypanosomiasis, also known as surra, in Arabian horses in the Khuzestan Province, after a hiatus of 60 years.
- The disease is caused by T. evansi, a hemoprotozoan parasite which can affect various equids like horses, donkeys, and mules, as well as camels.
Case Study and Presentation
- In September 2018, a 7-year-old Arabian mare from a 10-horse farm in the suburbs of Ahvaz City presented with a history of weight loss, poor appetite, and proximity to a camel herd.
- Symptoms included poor body condition, pale conjunctival and oral mucosal membranes, dehydration, tachycardia, and fever. Other horses in the herd also showed gradual weight loss and hyporexia, with two deaths reported.
Diagnostic Methods and Results
- Various diagnostic methods were used including physical examination, hematologic examination, and microscopic examination of a whole blood smear which confirmed the severe infection with Trypanosoma.
- A PCR assessment of a blood sample further confirmed the infection with T. evansi.
- The referred mare and seven non-referred patients from the herd received treatment with diminazene diaceturate and penicillin.
- Unfortunately, the referred mare died despite the treatment, while the remaining nonreferred horses recovered.
Implications of the Findings
- This study marks the first molecular diagnosis of surra in an Arabian horse in Khuzestan Province.
- The findings highlight the need for further investigation into surra as a re-emerging disease in this significant population of Arabian horses in the region.
Cite This Article
APA
Nikvand AA, Jalali SM, Bahrami S, Rahij Torfi H.
(2025).
Clinical occurrence of trypanosomiasis in Arabian horses from Ahvaz.
Vet Clin Pathol.
https://doi.org/10.1111/vcp.70003 Publication
Researcher Affiliations
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Shahid Chamran University of Ahvaz, Ahvaz, Iran.
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Shahid Chamran University of Ahvaz, Ahvaz, Iran.
- Department of Parasitology, Faculty of Veterinary Medicine, Shahid Chamran University of Ahvaz, Ahvaz, Iran.
- Graduated of Veterinary Clinical Pathology, Faculty of Veterinary Medicine, Shahid Chamran University of Ahvaz, Ahvaz, Iran.
Grant Funding
- SCU.VC1401.30378 / Shahid Chamran University of Ahvaz
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