Email updates

Keep up to date with the latest news and content from BMC Veterinary Research and BioMed Central.

Open Access Highly Accessed Research article

Within-host evolution of Brucella canis during a canine brucellosis outbreak in a kennel

Miklós Gyuranecz1, Brandy D Rannals2, Christina A Allen2, Szilárd Jánosi3, Paul S Keim2 and Jeffrey T Foster2*

Author Affiliations

1 Institute for Veterinary Medical Research, Centre for Agricultural Research, Hungarian Academy of Sciences, Budapest, Hungária körút 21, 1143, Hungary

2 Center for Microbial Genetics & Genomics, Northern Arizona University, 1298 S. Knoles Drive, Flagstaff, AZ, 86011-4073, USA

3 Veterinary Diagnostic Directorate, National Food Chain Safety Office, Budapest, Tábornok utca 2, 1143, Hungary

For all author emails, please log on.

BMC Veterinary Research 2013, 9:76  doi:10.1186/1746-6148-9-76

Published: 12 April 2013



Little is currently known about Brucella evolution within the host during infection. The current study is the first to employ fine-scale genotyping on an isolate collection derived from a Brucella canis outbreak. Eight isolates of B. canis, cultured from different tissues of three dogs (female, stud dog, puppy of another female) from a single kennel over three months were genetically characterized with a 15-marker multi-locus, variable-number tandem repeat (VNTR) analysis (MLVA) to assess the genetic relatedness of isolates and potential rapid mutational changes.


MLVA discriminated among the otherwise indistinguishable isolates from different animals and from isolates collected at different time points within each host, with different VNTR alleles being detected at multiple dates and tissue sites. We suspect that all isolates cultured from the female, puppy, and stud dogs originated from the same strain, with subsequent rapid in vivo mutations. However, high mutation rates and apparent in several of the loci prevented making definitive epidemiological relationships among isolates.


This investigation highlights the rapid in vivo genetic mutations of several VNTRs of B. canis over a short time period in the host and the emergence of alternate alleles. However, this work also suggests the challenges of using highly mutable VNTRs to infer epidemiological relationships of strains within a short duration outbreak.

Brucella canis; Brucellosis; Evolution; MLVA; VNTR