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Home / Equine Research Bank / Pathogens / Tulathromycin and Diclazuril Lack Efficacy against Theileria...
Pathogens (Basel, Switzerland)2023; 12(3); 453; doi: 10.3390/pathogens12030453

Tulathromycin and Diclazuril Lack Efficacy against Theileria haneyi, but Tulathromycin Is Not Associated with Adverse Clinical Effects in Six Treated Adult Horses.

Abstract: Equine theileriosis, caused by and , leads to anemia, exercise intolerance, and occasionally, death. Theileriosis-free countries prohibit the importation of infected horses, resulting in significant costs for the equine industry. Imidocarb dipropionate is the only treatment for in the United States, but lacks efficacy against . The goal of this study was to assess the in vivo efficacy of tulathromycin and diclazuril against . Fourteen -infected horses were utilized. Six were treated with eight weekly 2.5 mg/kg doses of tulathromycin. Three were treated daily for eight weeks with 2.5 mg/kg diclazuril. Three were pre-treated with 0.5 mg/kg diclazuril daily for one month to determine whether low-dose diclazuril prevents infection. Following infection, the dose was increased to 2.5 mg/kg for eight weeks. Two infected horses remained untreated as controls. The horses were assessed via nested PCR, physical exams, complete blood counts, serum chemistry panels, and cytology. Tulathromycin and diclazuril failed to clear and the treated and control groups exhibited similar parasitemia and packed cell volume declines. To obtain additional safety data on tulathromycin use in adult horses, necropsy and histopathology were performed on tulathromycin-treated horses. No significant lesions were detected.
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Publication Date: 2023-03-14 PubMed ID: 36986375PubMed Central: PMC10055745DOI: 10.3390/pathogens12030453Google 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 article focuses on understanding the effectiveness of Tulathromycin and Diclazuril in treating an infections parasitic disease in horses, known as Equine theileriosis. Despite administered treatments, the research found that these drugs were unable to eradicate the parasitic infection in the horses.

Objective of the Study

  • The primary goal of this research is to explore the efficacy of the Tulathromycin and Diclazuril drugs against Equine theileriosis, specifically caused by the parasite Theileria haneyi.
  • The study also aims to determine the potential negative effects of Tulathromycin on adult horses.

Methodology of the Research

  • A total of 14 horses infected with Theileria haneyi were used in the experiment.
  • These horses were split into different groups, where different dosages and combinations of Tulathromycin and Diclazuril were administered.
  • A control group consisting of two infected horses was also set, receiving no treatment for relative comparison with those receiving treatments.
  • Assessments were made using nested PCR, physical examinations, complete blood counts, serum chemistry panels, and cytology.

Results from the Study

  • Results showed that both Tulathromycin and Diclazuril were not successful in eliminating Theileria haneyi from the infected horses.
  • The levels of parasitemia (presence of parasites in the blood) and declines in packed cell volume were similar in both the treated horses as well as the control group.
  • As for the potential negative effects of Tulathromycin, the study did not find any significant lesions or harmful effects in the Tulathromycin-treated horses. Necropsies and histopathology were performed to gather this data.

Cite This Article

APA
Onzere CK, Hulbert M, Sears KP, Williams LBA, Fry LM. (2023). Tulathromycin and Diclazuril Lack Efficacy against Theileria haneyi, but Tulathromycin Is Not Associated with Adverse Clinical Effects in Six Treated Adult Horses. Pathogens, 12(3), 453. https://doi.org/10.3390/pathogens12030453

Publication

Pathogens (Basel, Switzerland)
ISSN: 2076-0817
NlmUniqueID: 101596317
Country: Switzerland
Language: English
Volume: 12
Issue: 3
PII: 453

Researcher Affiliations

Onzere, Cynthia K
  • Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164, USA.
Hulbert, Morgan
  • College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA.
Sears, Kelly P
  • Department of Clinical Science, Carlson College of Veterinary Medicine, Oregon State University, Corvallis, OR 97331, USA.
Williams, Laura B A
  • Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164, USA.
Fry, Lindsay M
  • Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164, USA.
  • Animal Disease Research Unit, USDA-ARS, Pullman, WA 99164, USA.

Grant Funding

  • 2090-32000-044-000-D / Agricultural Research Service - Pacific West Area
  • ARS 59-3022-1-003 / USDA ARS NBAF AGREEMENT

Conflict of Interest Statement

The authors declare no conflict of interest.

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Citations

This article has been cited 5 times.
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