Brucellosis is a bacterial infection that affects many animals including sheep. One of the symptoms of brucellosis in ewes is abortion. Ewes infected with brucellosis may abort their fetuses prematurely, leading to a decrease in the number of lambs produced. The bacteria can also affect the reproductive organs and cause infertility. In some cases, ewes infected with brucellosis may give birth to weak or stillborn lambs. Other symptoms of brucellosis in ewes may include fever, weight loss, and reduced milk production.