Collected reprints: Abstract 3260

Collected reprints

Abstract

Vranken, G.; Heip, C. (1983). Calculation of the intrinsic rate of natural increase, rm, with Rhabditis marina Bastian 1865 (Nematoda). Nematologica 29: 468-477

The life-cycle of Rhabditis marina Bastian 1865 was studied at 25°C and 20 promille salinity. The following demographic parameters were computed from life-table data : the intrinsic rate of natural increase (rm) = 0.914 day; net reproductivity (R0) = 400; minimum generation time (Tmin) = 4.5 days; cohort generation time (Tc) = 7.2 days; mean generation time (T) = 6.6 days; and the age of an adult female when a median egg is deposited (T) = 6.1 days. Several approximate equations used to estimate rm were compared with these life-table calculations. Some give erroneous estimations and should be used with extreme caution. For iteroparous organisms (including most free-living nematodes), Tmin only gives an indication of the development time and is therefore unsuitable for describing "mean generation time".


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