Health effects of low-level irradiation during development: experimental design and prenatal and early neonatal mortality in beagles exposed to 60Co gamma rays.
As part of a long-term study of the effects of irradiation during development, prenatal and early neonatal mortality were evaluated for beagles exposed in utero at 8 days postcoitus (dpc), 28 dpc, 55 dpc, or 2 days postpartum. Mean doses used were 0,0.16, or 0.83 Gy. A decrease in whelping rates was observed for female breeders irradiated at 8 dpc. There was a significant decrease in litter sizes from female breeders irradiated at 8 and 28 dpc. Both of these findings are indicative of increased embryonic mortality. There was a significant decrease in the percentage of females born after exposures given at 28 dpc, indicating a differential radiosensitivity by sex. A significant increase in early neonatal mortality up to 14 days of age was observed for beagles exposed 8 or 28 dpc, again with an excess mortality in females.
Angleton
G M
GM
Department of Radiology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins 80523.
Benjamin
S A
SA
Lee
A C
AC
D000818:Animals; D000831:Animals, Newborn / Q000254:growth & development / Q000528:radiation effects*; D003037:Cobalt Radioisotopes; D004285:Dogs; D005314:Embryonic and Fetal Development / Q000528:radiation effects*; D005260:Female; D005313:Fetal Death / Q000209:etiology*; D006283:Health Physics; D008098:Litter Size / Q000528:radiation effects; D008297:Male; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D012737:Sex Factors; D013223:Statistics as Topic; D014916:Whole-Body Irradiation
D003037:Cobalt Radioisotopes