Canine brucellosis is a contagious bacterial infection caused by the bacterium, Brucella canis (B. canis). This bacterial infection is highly contagious between dogs. Infected dogs usually develop an infection of the reproductive system, or a sexually transmitted disease. In dogs, canine brucellosis manifests with abortion outbreaks, reproductive failure, enlargement of lymph nodes, and occasionally affects the osteoarticular system, although the occurrence of asymptomatic infections in dogs are not uncommon.  Male dogs infected with brucellosis develop epididymitis, an infection in part of the testicle. A dog with a newly acquired infection will often have an enlarged scrotum or an enlarged testicle and may have a skin rash on the scrotum. The dog may be infertile. In chronic or long-standing cases, the testicles will atrophy or become shrunken. Female dogs infected with brucellosis develop an infection of the uterus; causing her to be infertile, have difficulty getting pregnant, or she may abort in the late stages of pregnancy. She often has a persistent vaginal discharge. Typically, a pregnant dog with brucellosis will abort at 45-55 days of gestation or will give birth to stillborn or weak puppies that may die a few days after birth. Although antibiotics (most often minocycline or doxycycline, possibly enrofloxacin) can be used to help control the infection, no treatment is completely effective at eliminating the bacteria, and any dog that has been infected with B. canis should be considered to be infected for life. Brucellosis is a zoonotic disease, or a disease that can be transmitted from animals to humans. Although people can become infected by coming in contact with infected animals, it is uncommon for a person to get a brucellosis infection from a dog.