Effects of Continuous Radiation on Chick Embryos and Developing Chicks

Abstract

Expts. were carried out to study the effects of continuous prolonged irradiation with large and small doses of radiation in relation to time intervals of exposure. Radioactive phosphorus P32 was the radiation source and chick embryos and growing chicks (White Leghorn) served as the biological material. P32 was given as KH2PO4 in amounts of 1000-2000 [mu]c./cc. The P32 concentrated largely in the bones of the embryos and chicks. The radiation caused over-all growth retardation, resulting in small but well proportioned birds. Both testes and ovaries were found to be among the most radiosensitive organs. The sper-matogenetic cells of the testis remained extremely radio-sensitive throughout their development, while the ova became more radio-resistant as they matured. Bone growth was retarded by radiation. The cartilage cells of the epiphysis were more radiosensitive than the osteoblasts and osteoclasts. After radiation ceased, the bones regained a normal histological structure but remained dwarfed.