Infection with Brucella canis in dogs leads to abortion, infection of the sexual organs in males, and infertility. The disease occurs throughout the world and primarily affects dogs. It spreads rapidly among closely confined dogs. Infection is transmitted through ingestion of contaminated materials or via sexual transmission. Both sexes appear to be equally susceptible. The primary sign of the infection in females is abortion during the last trimester of pregnancy without previous signs of abnormality. Abortion may occur during subsequent pregnancies. In males, the primary signs of infection are inflammation of the epididymides or testicles and reluctance to mate because of this inflammation. Transmission of brucellosis from dogs to humans occurs, but is quite rare. In humans, the disease can be very serious.

Brucellosis caused by Brucella abortus, B. suis, or B. melitensis is relatively rare in dogs. In cases that do occur, the dogs are usually around livestock, as they are the primary source of those strains of the bacteria.

The disease is diagnosed through laboratory tests. Spread of infection is controlled through isolation of infected dogs. Brucellosis is very difficult to treat successfully, and euthanasia of infected dogs is often recommended. In some states, cases of brucellosis must be reported to the health department. Dogs with a history of brucellosis cannot be bred.

Last full review/revision July 2011 by Cheri A. Johnson, DVM, MS, DACVIM (Small Animal); Brad E. Seguin, DVM, MS, PhD DACT; Autumn P. Davidson, DVM, MS, DACVIM; Fabio Del Piero, DVM, DACVP, PhD; James A. Flanders, DVM, DACVS; Mushtaq A. Memon, BVSc, MS, PhD, DACT; Paul Nicoletti, DVM, MS; Robert C. Rosenthal, DVM, PhD, DACVIM (Small Animal, Oncology), DACVR (Radiation Oncology)