Adults of Physa acuta, Draparnaud were exposed to the following doses of X-rays: 2, 4, 6, 8 and 10 KR at 200 R/min. The values of mortality, fecundity and fertility of the adults and those of viability of the embryos were recorded for 160 days after irradiation. The conclusions are the following: 1) mean length of adult life and of fecundity period was not reduced by doses until 10 KR; 2) fecundity, fertility and viability rates were reduced also by relatively low doses, f.i. 2 KR; 3) recovery of germ tissue was evident for individuals exposed to doses ranging from 2 to 10 KR.
Referenze Bibliografiche
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[3] J. H. MCGREGOR, Abnormal development of frog embryos as a result of treatment of ova and sperm with roentgen rays, «Science», 27, 445-446 (1908).
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[5] O. RAVERA, The effect of X-irradiation on various stages of life cycle of Physa acuta, Draparnaud, a freshwater Gastropod, «Symposium on the disposal of radioactive wastes into seas, oceans and surface water, Vienna 16-20/5/66», (in stampa) (1966).
[6] G. S. ROLLASON, X-radiation of eggs of Rana pipiens at various maturation stages, «Biol. Bull.», 97, 169-186 (1949).
[7] G. S. ROLLASON, The Cambridge Italian Dictionary, Cambridge, The University Press (1962).
Con il contributo del Ministero per i Beni e le Attività Culturali