Experimental Brucella canis infection in the monkey (Macaca arctoides).

Four stumptail Macaque monkeys (Macaca arctoides) were each inoculated with approximately 10(10) organisms from a culture of Brucella canis. Two animals were inoculated via the oral and conjunctival route and the other two monkeys were inoculated intravenously with the organisms. A fifth animal served as a control. Blood samples were taken at weekly intervals for hematological, serological and bacterialogical studies. The monkeys were killed at five and ten weeks post-inoculation and tissues taken from a variety of organs for bacterial culture. B. canis was isolated from the peripheral blood of inoculated monkeys for up to seven weeks post inoculation and all infected monkeys developed significant neutralizing antibody titers to the organism. The bacterium was isolated from some tissues, including the uterus of one monkey, in the two animals killed at five weeks post-inoculation. Focal granulomatous lesions were sometimes observed in the liver, spleen and lymphoid tissue of inoculated monkeys. Such lesions are similar to those described in other brucella infections. Human infections with B. canis have occurred and the possible dangers entailed in exposure to the organism should again be emphasized.