The Incidence of Endogenous Bacteremia in X-Irradiated Rabbits

Publisher Website
Google Scholar
Abstract
Daily blood cultures were made on young adult (snuffle-free) rabbits beginning on the 4th-6th day after exposure to 900 r total-body X-radiation and continuing to the 15th-20th day. Of 71 rabbits, 44 had a total of 238 blood cultures, all negative. Of these 44 animals, 28 (63%) died. Among 27 rabbits which had a total of 145 serial blood cultures, 39 were positive and 106 negative. Of these 27 animals, 81% died. In 14 of these 27 the results of the serial blood cultures were confirmed postmortem. The positive blood cultures never contained more than a few microorganisms. Of 48 rabbits sacrificed between the 4th and 35th days, the majority during the 2d week post4rradiation, only 2 had positive blood cultures, but 21 had positive cultures of liver and/or spleen, a finding which suggests that these components of the reticulo-endothelial system had been active in removing bacteria from the circulating blood. All the bacteria recovered ante- or post mortem were members of the rabbit''s normal intestinal flora. No evidence was encountered that bacteremia in the irradiated rabbit progresses to an overwhelming sepsis as it does in the mouse. It is concluded that the irradiated rabbit is able to combat endogenous infection more effectively than the mouse.