Serologic testing, although the most frequently used diagnostic method for detecting canine brucellosis, is subject to error because the lipopolysaccharide antigens of several bacterial species cross-react with Brucella canis. Further, serologic tests for Brucella spp. may be negative during the first 1–3 months of infection. After bacteremia ceases, titers can decline even though the organism persists in host tissues. Antibiotic therapy may also decrease the antibody levels.

This immunofluorescent assay is a highly sensitive, but not specific, screening test for B. canis infection. A negative test usually means there is no infection, although false negatives may occur in the first 8–12 weeks post-infection. A positive result may be due to infection or may be a false positive in about 50% of cases. Thus, any dog with a positive B. canis IFA test should have a confirmatory test performed.

Testing requires 1/2 mL of serum and takes 2-4 days. The test code is T530.

A highly sensitive and specific test for antibrucella IgG antibodies is used to confirm positive IFA screening test results. IgG antibodies appear 8–12 weeks post-infection and so false negative results may occur during this period.

The test requires 1/2 mL of serum and takes 7 days. The test code is S16131.

This agglutination test is required for export to certain countries such as Australia and New Zealand. Please contact the appropriate consulate to confirm each country's requirements.

The test requires 1.0 mL of serum and takes 10-14 days. The test code is 16003 for West Coast clients and 5020 for the other clients.

Culture of B. canis from tissues (blood, aborted fetuses, placenta, lymph nodes, spleen, male reproductive organs, semen, vaginal or uterine fluids) is the most definitive diagnostic procedure for detecting infection. Cultures may be positive within the first 1–3 months of infection, before Brucella antibodies can be detected. Isolation of B. canis can be time consuming, and may yield false negative results, especially in chronically infected dogs.

The test requires tissue or fluid be sent in a sterile container or Copan swab. Turn around time is 14 days. The test code is 1299.