Neosporosis in naturally infected pregnant dairy cattle

• Published in: Veterinary parasitology 2014-09, Vol.205 (1-2), p.85-91
• Main Authors: Mazuz, Monica L., Fish, Leah, Reznikov, Dror, Wolkomirsky, Ricardo, Leibovitz, Benjamin, Savitzky, Igor, Golenser, Jacob, Shkap, Varda
• Format: Article
• Language: English
• Subjects: Abortion; Abortion, Veterinary - parasitology; Animals; Cattle; Cattle Diseases - parasitology; Cattle Diseases - pathology; Coccidiosis - parasitology; Coccidiosis - pathology; Coccidiosis - veterinary; Dairy cattle; Female; Natural infection; Neosporosis; Pregnancy; Pregnancy Complications, Parasitic - pathology; Pregnancy Complications, Parasitic - veterinary
• ISSN: 0304-4017; 1873-2550
• DOI: 10.1016/j.vetpar.2014.06.009

Neosporosis caused by caused by the apicomplexan parasite Neospora caninum is one of the major causes of infectious abortion in bovines worldwide. A long-term prospective study was performed in a dairy herd endemic for N. caninum in order to analyze the impact of neosporosis on the proportion of aborting cows. A total of 1078 pregnant cows were tested for presence of antibodies and the proportion of abortions was calculated. The overall seroprevalence of N. caninum found in the herd was 35.5%. The percentage of abortions in seropositive cows was 3 times higher than in their seronegative counterparts (21.6 and 7.3%, respectively). No statistically significant association was found between the antibody level of positive during pregnancy and the proportion of aborting cows. However, 41.2% of the dams with antibody titers of 1:12,800 aborted. The risk of abortion for such dams was 2.7 times higher than for other seropositive cows which had lower titers of antibodies (p=0.0072). In the follow-up examinations of the seropositive cows during several pregnancies, the overall percent of abortions observed was significantly higher than in seronegative individuals (49.3 and 16.9%, respectively; p