Bacterial agents detected in a 10-year study of bovine abortions and stillbirths.

In a 10-year survey started in 1980, specimens from 8,995 bovine abortions and stillbirths were submitted to the South Dakota Animal Disease Research and Diagnostic Laboratory. Of these, 8,962 were suitable for some type of examination. Bacteria were determined to be the cause of 1,299 (14.49%). The 5 bacteria most commonly associated with bovine abortion or stillbirth were Actinomyces pyogenes, 378 (4.22%); Bacillus spp., 321 (3.58%); Listeria spp., 121 (1.35%); Escherichia coli, 98 (1.09%); and Leptospira interrogans, 79 (0.88%). Twelve other genera of bacteria were associated with > or = 10 abortions or stillbirths, and 12 more species were associated with < or = 10 abortions or stillbirths.