Bacteriological evaluations of swine exposed to lethal levels of gamma radiation

BACTERIOLOGICAL studies were conducted on swine exposed to a total air dose of 700 R at a rate of 1 R or 45 R/min. of gamma radiation. Blood, muscle, liver and mesenteric lymph nodes were cultured 10 days postirradiation and muscle again 5 days post-slaughter during which time the carcasses had hung in a cooler. A bacteremic state was not detected in the 1 R/min. group nor was there a greater incidence of bacterial isolates from the irradiated carcasses. All animals exposed to 45 R/min. developed a bacteremia at least once during the 10-day postirradiation period, but this bacteremia was not consistent within the group. Bacterial isolates from the muscles of irradiated animals at slaughter and 5 days later were consistently higher than isolates from controls. Pathologic changes observed in the tissues at slaughter were similar in both groups of animals but were more extensive in the swine exposed to 45 R/minute. Lesions seen were hemorrhagic in nature and indicated injury to the circulatory system.