The Mortality and Body Weight Response of Male Wistar Rats in the Lethal X-ray Dose Range

Abstract

Experiments were conducted to determine the LD_50/30 of Wistar strain male rats, aged 72 to 112 days, bred in National Institute of Radiological Sciences. The animals were irradiated at eight exposure levels between 600 and 90O R of X-rays at rate of 23.5 R/min. Probit analysis of mortality data yielded an LD_50/30 of 761.6±31.8 R. The body weight of the animals was decreased gradually after irradiation, reaching a minimum value at 4th day after the exposure. The body weight of 30-day survivors shows the second minimum value at 18-21 st day after irradiation.