Radiation Injury and Recovery in Swine

Abstract

Swine exposed to an initial dose of ionizing radiation were allowed 90 days of recuperation and then subjected to 50 r of [gamma] -radiation daily until death. The hogs lived from 83 to 385 days. The mean survival times were related to the size of the initial irradiation. Residual or irreparable damage at 90 days postirradiation (measured in terms of survival to daily irradiation) was not a constant per cent of initial dose. The dose at midcenter of the hog, calculated from measurements made within a hog carcass or a water-filled Lucite phantom, varied between 35 and 70% of the measured air dose, depending on the size of the hog and its position in the radiation field. One case of lymphatic leukemia occurred. Other clinical, hematologic, and pathologic changes were noted.