daphnid

Broods of female offspring are produced under favorable environmental conditions, and the daphnid population expands through asexual (parthenogenic) reproduction.

For at least the past three decades, the smaller Daphnia galeata mendotae and the larger Daphnia pulicaria have alternated as the numerically dominant daphnid species.

We have reported that the alkylphenol degradation product 4-nonylphenol alters the metabolic elimination of testosterone by the daphnid Daphnia magna (3).

Nevertheless, we support the view that where aquatic invertebrates may be exposed to endocrine-active substances, and because laboratory daphnid populations consist of parthenogenetic females, an alternative species to daphnids may be necessary for the assessment of chronic effects of endocrine disruptors in sexually reproducing Crustacea.

Each item was identified as daphnid, cyclopoid copepod, calanoid copepod, copepod nauplii, aquatic insect, or terrestrial insect and measured to the nearest 0.03 mm with a dissecting microscope.

The comparisons of the 50% inhibitory concentration (IC50) obtained from this work to rainbow trout assay daphnid (Daphnia magna) immobilized urease papain bromelain and Microtox(R) toxicity data are shown in Table

(2001), who found that the exposure of Daphnia magna to propiconazole interferes with the later stages of daphnid embryonic development, and that the toxicity was manifested largely via maternal exposure to the fungicide.

The literature suggests that the presence of filamentous algae reduces the food gathering capability of daphnids. This is most observed with large filaments: larger filaments entering the daphnid's feeding current are rejected, disrupting the feeding and consumption of edible algae (Burns 1968; Gliwicz 1977; Burns et al.

on daphnid reproduction and development will be presented and the use of

The number of FLB consumed by daphnid during the incubation time was plotted on a graph.

These salmonids would affect species number by feeding on large-bodied species such as daphnid cladocerans and calanoid copepods (Modenutti et al., 1998; Reissig et al., 2006).