RESUMO
Soil dwelling earthworms are now adopted more widely in ecotoxicology, so it is vital to establish if standardised test parameters remain applicable. The main aim of this study was to determine the influence of OECD artificial soil on selected soil-dwelling, endogeic earthworm species. In an initial experiment, biomass change in mature Allolobophora chlorotica was recorded in Standard OECD Artificial Soil (AS) and also in Kettering Loam (KL). In a second experiment, avoidance behaviour was recorded in a linear gradient with varying proportions of AS and KL (100% AS, 75% AS + 25% KL, 50% KS + 50% KL, 25% AS + 75% KL, 100% KL) with either A. chlorotica or Octolasion cyaneum. Results showed a significant decrease in A. chlorotica biomass in AS relative to KL, and in the linear gradient, both earthworm species preferentially occupied sections containing higher proportions of KL over AS. Soil texture and specifically % composition and particle size of sand are proposed as key factors that influenced observed results. This research suggests that more suitable substrates are required for ecotoxicology tests with soil dwelling earthworms.
Assuntos
Oligoquetos/fisiologia , Poluentes do Solo/toxicidade , Solo/química , Testes de Toxicidade , Animais , Aprendizagem da Esquiva , Biomassa , Ecotoxicologia , Organização para a Cooperação e Desenvolvimento EconômicoRESUMO
The late 20th century trend to delay birth of the first child until the age at which female fecundity or reproductive capacity is lower has increased the incidence of age-related infertility. In the female, the number of oocytes decreases with age until the menopause. Oocyte quality also diminishes, due in part to increased aneuploidy. A significantly lower pregnancy rate per stimulation and delivery rate per retrieval is found in women aged 40 to 45 years when compared with women aged 25 to 39 years. However, acceptable pregnancy can be achieved in woman aged 40 to 43 years (4 to 8%). Furthermore, very few women aged over 40 ask for IVF procedure.