background: neospora caninum is considered one of the major causes of repeated abortions in livestock. this study aimed to determine the seropositivity to n. cani-num using indirect elisa and the influence of the infection on the occurrence of abortions in selected dairy herd in slovakia. method:blood samples were obtained from 490 cattle over a period of two years and were tested for n. caninum antibodies using indirect elisa. results:the presence of specific antibodies in the herd was detected in 118 (24.1%) cows. according to selected groups; 117 (41.0%) cows with a history of abortion, 65 (43.3%) heifers and 223 (2.2%) cows without abortions were tested positive to neospora. vertical transmission of n. caninum dominated in examined herd and the relative risk (rr) of dam-daughter seropositivity in progenies of sero-positive mothers was 2.1 times higher than in progenies of seronegative dams. mo-lecular analyses of aborted foetuses of seropositive mothers showed the presence of neospora dna. however, 23 (28.1%) of heifers born to seronegative cows were seropositive, indicating also the postnatal transmission of the infection from the environment. conclusion:study revealed significant correlation between the presence of specif-ic antibodies and the occurrence of abortions, the risk of abortion in seropositive animals was 3.8 times higher than in seronegative ones. incorrect farm manage-ment contributed to spread and circulation of neosporosis in entire dairy herd what could significantly impair the reproduction and economic parameters of breeding. |