• Open Access

Bartonella spp. Infection in Healthy and Sick Horses and Foals from the Southeastern United States

Authors

  • N.A. Cherry,

    1. Intracellular Pathogens Research Laboratory, Center for Comparative Medicine and Translational Research, College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina
    Search for more papers by this author
  • S.L. Jones,

    1. Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NorthCarolina
    Search for more papers by this author
  • R.G. Maggi,

    1. Intracellular Pathogens Research Laboratory, Center for Comparative Medicine and Translational Research, College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina
    Search for more papers by this author
  • J.L. Davis,

    1. Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NorthCarolina
    Search for more papers by this author
  • E.B. Breitschwerdt

    Corresponding author
    • Intracellular Pathogens Research Laboratory, Center for Comparative Medicine and Translational Research, College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina
    Search for more papers by this author

Corresponding author: E.B. Breitschwerdt, DVM, Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, 1060 William Moore Dr, Raleigh, NC 27607; e-mail: ed_breitschwerdt@ncsu.edu.

Abstract

Background

Bartonella species bacteremia has been identified in numerous animal species. These bacteria cause, or have been associated with, a spectrum of clinical manifestations in dogs and human patients. The frequency of exposure to or infection with Bartonella spp. among healthy and sick horses has not been reported.

Objective

To test healthy and sick horses and sick foals from the southeastern United States for serological, microbiological, and molecular evidence of Bartonella infection.

Animals

Forty-seven healthy horses, 15 sick foals, 22 horses with musculoskeletal manifestations, and 8 horses with colic were tested for Bartonella.

Methods

IFA serology and PCR before and after BAPGM (Bartonella alpha-Proteobacteria Growth Medium) enrichment blood culture.

Results

Bartonella antibodies were not detected in foals or horses. Three Bartonella species, B. henselae, B. vinsonii subsp. berkhoffii (genotypes I and III), and a Bartonella species with closest homology to Candidatus Bartonella volans, were PCR-amplified and sequenced from blood or BAPGM enrichment blood culture samples from 1/47 healthy horses, 3/15 sick foals, 5/22 horses with musculoskeletal disease, and 0/8 horses with colic.

Conclusions and Clinical Importance

Horses in the southeastern United States are naturally infected with B. henselae, B. vinsonii subsp. berkhofii genotypes I and III, and a bacteria most similar to Candidatus Bartonella volans. Antibodies were not detectable by indirect fluorescent antibody assay (IFA) testing in bacteremic foals or horses, and prolonged enrichment culture for periods up to 21 days were necessary to document bacteremia in most horses. Further investigation into the pathogenic potential of Bartonella spp. infection in horses is warranted.

Ancillary