title: [Endogenous biorhythms of the specific growth rate in individual development of Lymnaea stagnalis (Lymnaeidae, Gastropoda)].
abstract: On the basis of data on the growth of freshwater gastropods Lymnaea stagnalis, the dependence of the specific growth rate on age in the late postlarval ontogeny is calculated. The presence of two endogenous biorhythms of the specific growth rate with periods of 10.3 weeks and 6.5 weeks was revealed using singular spectrum analysis. Local maxima of both biorhythms in different individuals fall on the same age, and their periods are approximately the same in all animals studied and remain unchanged during individual postlarval development. The biorhythm with a period of 10.3 weeks is decaying, its amplitude is reduced from 3.2 year(-1) (at the age of 10 weeks) to 0.8 year(-1) (at the time of death of the shellfish). The biorhythm with a period of 6.5 weeks is non-decaying and has an average amplitude of 0.8 year(-1).
authors: A A
authors: AA
authors: Zotin
authors: S Iu
authors: SIu
authors: Kleĭmenov
mesh_terms: D000818:Animals; D005618:Fresh Water; D008195:Lymnaea / Q000254:growth & development / Q000502:physiology; D010507:Periodicity