Vibriosis of cattle is a widespread venereal disease which causes considerable financial loss to the dairy and beef cattle industries. When the disease is first introduced into a herd the breeding program may be set back 6 months or more. Repeat breeding is the primary manifestation of the infection in heifers and cows. Many of the infected females return in heat 27 or more days after service. These prolonged estrus cycles are probably the result of embryonic death caused by vibrionic endometritis. The estrual mucus is often cloudy in recently infected cattle. The inflammatory lesions in the reproductive organs are not severe enough to produce alterations which can be detected by rectal palpation. Recognizable abortions may occur at any stage of pregnancy, but they are not as prominent a manifestation of the disease as repeat breeding. The majority of cows recover within a few months but bulls appear to harbor the Vibrio fetus organism indefinitely. There are no clinical signs of the presence of the organism in the bull.