No abstract

In the present study, the effects of selenium (Se) enrichment on the rotifer, Brachionus plicatilis, were investigated. Based on the results of six Se treatments obtained from triplicate experiments, we found that the efficiency of bioaccumulation by Se from non‐acid‐soluble sources was 62‐fold greater than that from acid‐soluble sources (Se‐Chlorella 15.6 ± 1.81% vs. selenite 0.25 ± 0.03%). However, supplementation of both acid‐soluble Se at low concentrations (≤40 µg per thousand rotifers) and Se‐Chlorella enhanced rotifer lifespan, increased the rate of spawning, inhibited lipid peroxidation, decreased levels of intracellular oxidization products and maintained the stability of mitochondrial membranes. These positive effects were correlated with the activities of antioxidant enzymes (e.g. catalase‐ and guaiacol‐dependent peroxidase) which increased along with the low Se concentrations (<80 µg per thousand rotifers). In contrast, the opposite effects were found when the rotifers were exposed to high Se concentrations (≥80 µg per thousand rotifers). The antioxidation and toxicity effects appeared to be correlated with the levels of total Se bioaccumulation. Above all, selenite, which is more toxic than Se‐chlorella, is less readily accumulated and biologically active. Se‐enriched rotifers fed by Se‐Chlorella are a fish larvae food supplement in aquaculture.