ABSTRACT
Seroprevalence varied from 0% to 64% depending on the serological test and cut-off employed, age and type of sheep, and gender and management of animals. When bulk milk from 613 dairy sheep herds in Sardinia, Italy, was investigated, 44.2% of the herds were positive. The economic, clinical, and epidemiologic importance of N. caninum infection in sheep remains uncertain. Sheep can be experimentally infected using different routes, strains, and doses of N. caninum, and they represent an excellent ruminant model for bovine neosporosis. Sheep develop good humoral and cellular responses to N. caninum in experimental and natural infections using a variety of tests and antigens. Similar to cattle, chronically infected sheep can abort from neosporosis due to exogenous infection or due to endogenous transplacental transmission of N. caninum to the fetus during second pregnancy. A dog fed a brain homogenate of a 4-month-old sheep in Brazil excreted N. caninum oocysts 10–16 days later.
