Seroprevalence and potential risk factors of Neospora caninum infection in dairy cattle in Croatia

Neospora caninum, a cyst forming coccidian parasite, is an important cause of abortion in cattle worldwide. The present work aims to update knowledge of the presence of Neospora in cattle from Croatia. The survey was carried out on dairy cows in the Bjelovar-Bilogora County in northwest Croatia (2652 km(2)). The cows were selected by simple randomization from county daily producer records. Cows were tested for the presence of N. caninum antibodies with the Neospora-Ab iscom enzyme-linked immunoassay kit (SVANOVIR). is caninum, antibodies were detected in 23 from 395 (5.6%, confidence interval (CI); CI 95%; 3.5 to 8.1) lactating cows. Epidemiological studies of potential risk factors, such as the presence of a dog, cat, swine, free range poultry and management practices, such as silage processing and pasture practising showed that none of these factors was associated with N. caninum antibodies. Seropositivity of cows was associated to abortion (odds ratio (OR); OR = 8.307, P = 0.002) and to purchasing of replacement animals from other sources (OR = 5.27, P = 0.0002). A strong correlation was also found between antibodies, history of abortion and origin (imported animals) of heifers or cows (OR = 5.52; P = 0.001).