AHL LabNote 61-Brucella Canis Resources and Information for Veterinarians

With the current interest in this testing at AHL, please see below a brief review of testing and some resources for more in-depth information.

SCREENING TEST

The only test offered at AHL is the Brucella canis immunofluorescence (IFA) test (code bcat). The RSAT test for Brucella canis is currently not available.

Sample required: 0.5 mL serum. Collect in red-top vacutainer tube or equivalent. Ship in insulated container with freezer packs. TAT 1-8 days.

CONFIRMATORY TESTS

Further testing to confirm IFA-positive results can be done by PCR or ME tube agglutination test.

PCR (send out)

Can be performed from blood (EDTA), vaginal swabs, preputial swabs or urine.
Positive results are confirmatory. Negative results do not rule out brucellosis so it should not be used as a screening test.

Please note – both PCR and culture on blood may only be positive during the initial acute febrile stage of the disease.

ME tube agglutination test (send out)

Another confirmatory test that can be done on IFA-positive serum samples.

Because the organism can be sequestered in the body, dogs can exhibit a range of serological reactions over time, potentially alternating positive and negative results. In cases of chronic infection, serology is not a useful tool to monitor response to therapy.

RESOURCES

Dr Scott Weese - Worms and Germs Blog

https://www.wormsandgermsblog.com/2019/03/articles/animals/dogs/brucella-canis-in-imported-dogs-ontario/

https://www.wormsandgermsblog.com/2019/03/articles/animals/dogs/brucella-canis-ontario/

CDC Emerging and Infectious Disease article

https://wwwnc.cdc.gov/eid/article/24/8/17-1171_article

Brucella canis factsheet (Center for Food Security and Public Health)

Best Practices for Brucella canis Prevention and Control in Dog

Tim Pasma

Client Services Veterinarian

Animal Health Lab, University of Guelph

tpasma@uoguelph.ca