Effects of acute gamma radiation on the reproductive ability of the earthworm Eisenia fetida

• Published in: Journal of environmental radioactivity 2015-02, Vol.140, p.11-15
• Main Authors: Sowmithra, K., Shetty, N.J., Harini, B.P., Jha, S.K., Chaubey, R.C.
• Format: Article
• Language: English
• Subjects: Animals; Cocoon; Dose-Response Relationship, Radiation; Eisenia fetida; Exposure; Gamma radiation; Gamma Rays; Hatchling; Male; Oligochaeta - radiation effects; Reduction; Seminal vesicle; Seminal Vesicles - radiation effects; Structural damage; Vesicles; Webs; Weight reduction
• ISSN: 0265-931X; 1879-1700
• DOI: 10.1016/j.jenvrad.2014.10.010

Earthworms are the most suitable biological indicators of radioactive pollution because they are the parts of nutritional webs, and are present in relatively high numbers. Four months old Eisenia fetida were exposed to different doses of gamma radiation, namely 1, 2, 3, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55 & 60 Gy to study the effects of radiation on different reproductive parameters. The number of cocoons laid and the hatchlings emerged were recorded for all the selected doses. There was no reduction in cocoon production, however; decreasing size and weight of the cocoons was observed from the samples exposed to 20 Gy and above doses. Significant reductions in the hatchlings were recorded in earthworms exposed to 10 Gy and above doses. The dose response curves for a percentage reduction in hatchlings were constructed. Exposure to radiation dose of 1 and 2 Gy did not show any reduction, however, there was ≈10%, ≈50% and ≈90% decrease in the hatchlings in samples exposed to 3, 15 and 45, 50, 55 and 60 Gy doses respectively. Delayed hatchability was also reported at al exposure level. Histology of irradiated earthworms revealed that the structural damage in the seminal vesicles was prominent at the exposed dose of 3 Gy onwards with complete degeneration on exposure to 60 Gy of gamma radiation. •Eisenia fetida exposed to several doses of Ɣ-radiation to study the impact on reproduction.•There was no reduction in the cocoon production however.•There was reduction in size, weight and change in shape of the cocoons observed.•Reduction in number of hatchlings and degradation of seminal vesicles was pragmatic.