Repetitive abortion in Neospora-infected ewes

Pregnant ewes inoculated with cultured Neospora caninum tachyzoites in 1995 , 1996, or 1995 and 1996 aborted or delivered weak or clinically normal lam bs in 1996. Nine of 11 ewes in the study had previously produced infected l ambs or fetuses after being experimentally infected in 1995. Fetuses and la mbs produced in 1996 showed histologic lesions and zoites indicative of Neo spora. Serologic responses and production of infected fetuses/lambs indicat ed systemic neosporosis in the ewes during gestation, although tachyzoites could not be cultured from maternal tissues. The repetitive infection of fe tuses, and resulting clinical and histopathologic findings in the present s tudy are similar to those reported in naturally infected cattle, adding to the already established similarities of neosporosis between sheep and cattl e. (C) 1999 Elsevier Science B.V. All rights reserved.