Manipulating the timing of maturation and competence for fertilization and development of oocytes from the semelparous polychaete Nereis (Neanthes) virens Sars

Abstract

Summary The timing of final maturation and competence for fertilization of oocytes from individuals of Nereis (Neanthes) virens was investigated. In the first experiment, one group was decerebrated and the other was not. Both groups were placed into a long-day photoperiod (LD 16:8). The oocytes from the decerebrated animals became fertilizable and successfully developed to the larval stage in advance of the other group. In the second experiment one group was maintained in long-day and the other in short-day photoperiod (LD 8:16). The oocytes from the animals exposed to long-day photoperiod became fertilizable in advance of those maintained in short-day photoperiod. These results indicate an influence of external photoperiod on the final stages of oocyte maturation resulting in advanced fertilizability and successful larval development.