ABSTRACT
B. suis biovar 2, however, causes a disease that is different in some respects from that caused by the other two biovars that affect the pig. 1 The European hare (Lepus capensis) is also a principal host of biovar 2 and can form a reservoir of infection from which pigs, both domestic and wild, may become infected. 2 Nevertheless, infection with biovar 2 spreads as readily among pigs both within and between herds as the other two biovars. In pigs, miliary brucellosis of the uterus is a feature of the disease caused by biovar 2. Otherwise, it closely resembles that caused by biovars 1 and 3. B. suis biovar 2 also differs in not being a human pathogen. Its geographic distribution is confined to Europe in a broad band between Scandinavia and the Balkans. The disease in hares is characterized by the formation of nodules, varying in size from a millet seed to a cherry or even larger; these often become purulent. Such nodules may occur in almost any location, sometimes subcutaneously or intramuscularly, but most often in the reproductive organs. The bodily condition of the hare may be surprisingly unaffected. In the rest of this chapter we shall be mainly concerned with biovars 1 and 3 and the disease they cause.
