Energy sources utilized by Vibrio fetus.

Vibrio fetus is significant in the sheep and cattle industries because it causes abortion and infertility. However, little is known of the metabolism of this organism. Smith and Taylor (1919) described V. fetus as being relatively difficult to cultivate immediately after isolation, but after repeated transfers cultivation became less difficult. The organism produced no gas and the reaction remained neutral or slightly acid in fermented bouillon with 0.1 per cent glucose, lactose, or sucrose. A reduced oxygen tension was reported to be necessary for growth. According to Stockman (1919), V. fetus can not grow either in a free supply of air or under strictly anaerobic conditions. Plastridge and Williams (1943) found no evidence for acid production by V. fetus with arabinose, glucose, dextrin, raffinose, salicin, sucrose, sorbitol, or trehalose. This organism is apparently microaerophilic (May, 1953; Reich et al., 1956; Kiggins and Plastridge, 1956). V. fetus appears to be totally lacking in fermentative ability, and therefore is restricted to oxidative processes for obtaining energy. Since little is known of the metabolic character of microaerophilic bacteria, it was thought that a study of the compounds which could be used as energy sources would be of interest.