title: Gamma (60)Co DL(50/30) of Biomphalaria glabrata (SAY, 1818).
abstract: The variation of resistance to (60)Co gamma-rays of Biomphalaria glabrata was studied. A population of 480 mollusks was observed during 30 days - distributed in 8 groups of snails isolated and 8 groups of snails in colonies - after exposure (30 snails per group per dose) to increasing doses of gamma radiation. Doses of 10, 20, 40, 60, 80, 160, 320 and 640 Gy from a Gamma-cell (60)Co irradiator, were applied to the test groups and two groups control (non-irradiated) of snails - isolated and colony - were kept apart. After have been exposed, the snails were drew back to the aquaria where they were maintained before. The survival was estimated on a daily score of the alive animals in each group-dose, starting after the irradiation exposure day. As a result, the survival self-fertilization forms (DL(50/30) = 218.2 Gy) was found greater than in cross-fecundation forms. These data point to a low radio-resistance on the cross-fertilization forms - the sexual reproductive form - which is most found in nature. The lower radio-resistance of the cross-fertilization forms suggests the presence of some sex-linked hormonal factor related to this phenomenon.
authors.affiliation: Depto. de Biofísica e Radiobiologia, Centro de Ciências Biológicas, Universidade Federal de Pernambuco, Recife, PE, Brasil.
authors.forename: E B
authors.initials: EB
authors.lastname: Carvalho
authors.forename: A M
authors.initials: AM
authors.lastname: Melo
authors.forename: M A
authors.initials: MA
authors.lastname: Motta
mesh_terms: D000818:Animals; D001700:Biomphalaria / Q000502:physiology / Q000528:radiation effects*; D005720:Gamma Rays; D007928:Lethal Dose 50; D012098:Reproduction / Q000528:radiation effects