Usability of selenium fortified Chlorella diet for rotifer resting egg production and hatching

Abstract

Our previous study elucidated that commercial Chlorella vulgaris induces the resting egg production of the euryhaline rotifer Brachionus plicatilis sensu stricto caused by selenium (Se) fortification. This study confirmed production efficiency and hatchability of resting eggs with the commercial Se-fortified C. vulgaris. The aforementioned parameters were compared to those with Tetraselmis tetrathele (control) which is an optimal diet for resting egg production and hatching. The rotifers pre-cultured with Nannochloropsis oculata, and the produced resting eggs were employed to test diet effects. The hatching rate of collected resting eggs was estimated and then hatchlings were used for next generation culture. For the resting egg production with two different diets, T. tetrathele induced significantly higher productivity in the first generation, while no differences were observed in the second generations between two diets T. tetrathele and C. vulgaris. The resting eggs with N. oculata showed 6.0% of hatching rate, whereas it notably increased with two tested diets. The highest hatching rate was observed with C. vulgaris feeding (74.0-81.0%) through the all tested generations. The obtained results exhibit the possibility of C. vulgaris feeding for the mass production of rotifer resting eggs.