Tidsskriftspublikasjon » Vitenskapelig artikkel
Effects of season and maternal food on Calanus finmarchicus reproduction, with emphasis on free anmino acids
Marine Biology ; Volume 142. p. 1141–1151. 2003
Helland, Synnøve; Nejstgaard, Jens Christian; Humlen, R.; Fyhn, Hans Jørgen; Båmstedt, Ulf
Effects of maternal food environment and season were examined during spring and autumn on females, eggs and nauplii of Calanus finmarchicus, in different natural prey suspensions or cultures of Rhodomonas baltica. Females sampled in spring were in general larger, had higher protein content, and showed higher egg production and hatching rates, than in autumn. The cumulative egg production was almost double in spring compared to autumn (females fed R. baltica). Females had higher content of free amino acids (FAA) and free essential amino acids (EAA) in autumn than in the spring. Also, the FAA contents in eggs and nauplii were higher in autumn than in spring. In contrast, the composition of EAA in eggs was constant between seasons, indicating maternal regulation. The highest cumulative egg production was correlated with a high similarity in the free pool of EAA in the food suspension and the female copepod. Thus, the data support the hypothesis that similarity in the free pool of EAA of diet and female promotes high fecundity and egg hatching success in C. finmarchicus.