There are several distinct pathogens: Brucella abortus, B. canis, B. melitensis, B. suis, whose identifications correlate with their reservoirs, respectively, cattle, dogs, goats and sheep, and pigs.

• 有若干不同的病原体:流产布鲁氏杆菌、犬布鲁氏杆菌、山羊布鲁氏杆菌、猪布鲁氏杆菌等，其识别与对应的贮藏宿主有关，即分别为牛、犬、山羊和绵羊、猪。