These figures could be substantially higher in wet years when hay is put up in poor condition. The infection can later spread to other tissues in the uterus and to the fetus itself.
Abortions occur later in the pregnancy, most often between the sixth and eighth month.
These lesions are seen most often around the eyes and face, the shoulders, and over the back and sides. They have a grayish appearance, are irregularly shaped and tend to coalesce. Often there is a chalky deposit on the surface of the skin which itself may be thickened and wrinkled. The afterbirth sometimes has more distinctive lesions. The infecting organisms can readily be identified in the placental lesions by microscopic examination.