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Tropical animal health and production2025; 57(2); 72; doi: 10.1007/s11250-025-04321-x

Epidemiology and genetic diversity of Theileria equi and Babesia caballi in draft horses in the Distrito Federal, Brazil.

Abstract: Equine piroplasmosis (EP) is a reportable disease according to the World Organization for Animal Health (WOAH), caused by Babesia caballi, Theileria equi and T. haneyi. This syndrome is prevalent in tropical and subtropical regions, including various areas in Brazilian. This study examines EP in the Distrito Federal, Brazil, focusing on prevalence, epidemiological characteristics, and circulating genotypes. Epidemiological data and whole blood samples were collected from horses in the Distrito Federal. DNA was analyzed using qPCR for Theileria sp. and B. caballi, followed by cPCR for 18S rDNA of Theileria sp and rap-1 gene for B. caballi and phylogenetic analysis. Results showed a high EP prevalence (56.23%) among the horses: 49.88% for Theileria sp, 1.47% for B. caballi and 4.89% for both. Phylogenetic analysis indicated genetic similarities with other countries, identifying of T. equi genotypes A and C and B. caballi genotype A. Factors linked to infection, included animals older than five years (p-value = 0.04; OR = 1.71, CI = 1.01-2.87) and health conditions (p-value = 0.049; OR = 1.91, CI = 1.003-3.64) as significantly associated with positivity for Theileria sp. and/or B. caballi. This study contributes to the awareness of the circulation and distribution of T. equi and B. caballi genotypes in Brazil, highlighting the importance of health condition and age as associated factors for infection. These findings deepen our understanding of the need for ongoing surveillance and control measures to manage EP effectively.
Publication Date: 2025-02-19 PubMed ID: 39969660PubMed Central: 10675911DOI: 10.1007/s11250-025-04321-xGoogle Scholar: Lookup
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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 examines equine piroplasmosis in Brazil’s Distrito Federal, its prevalence, the epidemiological characteristics, and the types of circulating genotypes. Study results portrayed a high occurrence of the disease, particularly in mature horses and those with certain health conditions, highlighting the need for ongoing surveillance and control measures.

Objectives of the Study

  • The main aim of the study was to investigate the prevalence and epidemiological characteristics of equine piroplasmosis (EP) in the Distrito Federal, Brazil.
  • The study aimed to analyze the genetic diversity and circulation of various genotypes of Theileria equi and Babesia caballi, the causal agents of piroplasmosis, in the region.

Methods

  • Epidemiological data and blood samples were collected from horses within the region.
  • The researchers used quantitive PCR to analyze the DNA for Theileria sp. and B. caballi.
  • This was followed by conventional PCR for 18S rDNA of Theileria sp and rap-1 gene for B. caballi and then phylogenetic analysis to identify circulating genotypes.

Key Findings

  • The study found that there was a high prevalence (56.23%) of EP in the region: 49.88% for Theileria sp, 1.47% for B. caballi and 4.89% for both.
  • The phylogenetic analysis revealed genetic similarities with those found in other countries, identifying genotypes A and C of T. equi and genotype A of B. caballi.
  • Factors associated with infection included horses aged over five years and certain health conditions.

Significance of the Study

  • This study adds significantly to the knowledge of the epidemiology and circulation of T. equi and B. caballi genotypes in Brazil.
  • The findings demonstrate the need for continual surveillance and control measures for effective EP management.
  • The study’s identification of risks associated with age and health conditions can guide veterinarians and farmers in understanding which animals may be more prone to infection, and in implementing preventive measures.

Cite This Article

APA
Fernandes TA, Paulino PG, Dos Santos Juliano D, Rabello CA, de Oliveira NVB, de Souza Santana M, Peckle M, Massard CL, da Costa Angelo I, Jacob JCF, Santos HA. (2025). Epidemiology and genetic diversity of Theileria equi and Babesia caballi in draft horses in the Distrito Federal, Brazil. Trop Anim Health Prod, 57(2), 72. https://doi.org/10.1007/s11250-025-04321-x

Publication

ISSN: 1573-7438
NlmUniqueID: 1277355
Country: United States
Language: English
Volume: 57
Issue: 2
Pages: 72

Researcher Affiliations

Fernandes, Thais Alves
  • Department of Epidemiology and Public Health, Federal Rural University of Rio de Janeiro (UFRRJ), Seropedica, RJ, Brazil.
Paulino, Patrícia Gonzaga
  • Department of Epidemiology and Public Health, Federal Rural University of Rio de Janeiro (UFRRJ), Seropedica, RJ, Brazil.
Dos Santos Juliano, Daniele
  • Department of Epidemiology and Public Health, Federal Rural University of Rio de Janeiro (UFRRJ), Seropedica, RJ, Brazil.
Rabello, Carla Alves
  • Department of Epidemiology and Public Health, Federal Rural University of Rio de Janeiro (UFRRJ), Seropedica, RJ, Brazil.
de Oliveira, Nádia Valesca Biral
  • Department of Epidemiology and Public Health, Federal Rural University of Rio de Janeiro (UFRRJ), Seropedica, RJ, Brazil.
de Souza Santana, Matheus
  • Department of Epidemiology and Public Health, Federal Rural University of Rio de Janeiro (UFRRJ), Seropedica, RJ, Brazil.
Peckle, Maristela
  • Department of Animal Parasitology, Federal Rural University of Rio de Janeiro (UFRRJ), Seropedica, RJ, Brazil.
Massard, Carlos Luiz
  • Department of Animal Parasitology, Federal Rural University of Rio de Janeiro (UFRRJ), Seropedica, RJ, Brazil.
da Costa Angelo, Isabele
  • Department of Epidemiology and Public Health, Federal Rural University of Rio de Janeiro (UFRRJ), Seropedica, RJ, Brazil.
Jacob, Júlio César Ferraz
  • Department of Animal Reproduction and Evaluation, Federal Rural University of Rio de Janeiro (UFRRJ), Seropedica, RJ, Brazil.
Santos, Huarrisson Azevedo
  • Department of Epidemiology and Public Health, Federal Rural University of Rio de Janeiro (UFRRJ), Seropedica, RJ, Brazil. huarrisson@yahoo.com.br.

MeSH Terms

  • Animals
  • Theileria / genetics
  • Theileria / isolation & purification
  • Horse Diseases / epidemiology
  • Horse Diseases / parasitology
  • Horses
  • Theileriasis / epidemiology
  • Theileriasis / parasitology
  • Babesia / isolation & purification
  • Babesia / genetics
  • Brazil / epidemiology
  • Babesiosis / epidemiology
  • Babesiosis / parasitology
  • Phylogeny
  • Genetic Variation
  • Prevalence
  • Male
  • Female
  • Genotype
  • DNA, Protozoan / analysis
  • DNA, Protozoan / genetics
  • RNA, Ribosomal, 18S / analysis
  • RNA, Ribosomal, 18S / genetics

Grant Funding

  • 313753/2021-0 / Conselho Nacional de Desenvolvimento Cientu00edfico e Tecnolu00f3gico
  • 403524/2023-7 / Conselho Nacional de Desenvolvimento Cientu00edfico e Tecnolu00f3gico
  • E-26/201.342/2021 / Fundau00e7u00e3o Carlos Chagas Filho de Amparo u00e0 Pesquisa do Estado do Rio de Janeiro

Conflict of Interest Statement

Declarations. Ethical approval: Blood samples were collected from horses with prior authorization from their guardians and approval from the Research Ethics Committee of the Federal Rural University of Rio de Janeiro (UFRRJ), under number 845/2016, and the ethics committee for the use of animals at the UFRRJ Veterinary Institute, under number 5268240716. Consent to participate: All authors voluntarily participated in the study. Consent for publication: The final manuscript was read and approved by all authors. Conflict of interest: The authors declare that they have no conflict of interest.

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