Variations in the Life-Cycle Parameters and Population Growth of Rotifer Brachionus Plicatilis Under the Stress of Microplastics and 17β-Estradiol

This study compares the effect of different diets on population growth, fecundity rate, production, and cyst hatching efficiency of the rotifer Brachionus plicatilis. Microalgae were cultured using filtered and sterilized seawater at 25 and 26ºC. The volume of the containers for algae, bread yeast, and rotifer was duplicated daily from 31mL to 16L in nine days. Rotifers were cultured at 25°C and 35o/oo salinity. The mean values of daily population growth rate for the rotifers fed on C. muelleri, I. galbana and bread yeast were 0,91, 0,89 and 0,87 daily counts, respectively.  After 10 cultured days, fecundity was 72%, 63% and 36% using C. muelleri, I. galbana and bread yeast, respectively. The highest mean value for cysts production was 4 064 000 cysts found from 63 243 (1,55%) rotifers fed on C. muelleri. Hatching efficiency after 36 hours of cysts from rotifers fed C. muelleri was 51 500 (94,3%) new borns, followed by 45 000 (93,3%) with I. galbana, and 31 000 (92,6%) with bread yeast. C. muelleri is a good food source for B. plicatilis.KEY WORDSFecundity, feeding, hatching, salinity, temperature