Study on some biological characteristics of a freshwater rotifer species (Brachionus rubens Ehrenberg 1838)

Abstract

The study was performed with the aim to determine the life cycle, fecundity, suitable environment parameters (temperature and pH) for development of a freshwater rotifer species this could be served as basic information for formulation of mass culture of this species. The study was implemented in laboratory condition including (i) effects of pH and temperature on life cycle of B. rubens; (2) reproductive characteristics of B. rubens. Experiments were set up in 30ml cups with treated water containing 1 rotifer each with 10 replicates. The results showed that under pH of 8, life span of B. rubens was 4.08±0.13 days and produced 5.90±0.38 eggs. At 22℃ the life span was was 6.90±0.57 days with 11.00±2.05 eggs . However, at 28℃, life span of B. rubens was shorter, 4.80±0.20 days. Under this temperature, the mean maturation, embryonic development duration, spawning interval and mean fecundity were 14.05±0.73 hours, 9.82±0.39 hours, 3.31±0.70 hours and 6.50±0.34 eggs, respectively().