Rotifers are valuable live food for the culture of the larvae of most fish species. Several characteristics of rotifers including their very small size have contributed to their usefulness as good prey for active larvae (Arimoro, 2006). With increased demand for live foods in aquaculture, attempts have been made toward high density rotifer culture (Yoshimura et al., 2003). Culture density is among the factors which affects population dynamics of rotifers (Gilbert, 2004). It has also been suggested that the mode of reproduction and cyst production can be governed by rotifer density (Lubzens and Zmora, 2003). Thus, this study aimed to evaluate the effects of culture density on population growth parameters of two Brachionus rotifer strains from Iran, in a laboratory scale.
