21 The effects of prey density (0.1, 1 and 10 rotifer ml ) on feeding, oxygen uptake, growth, survival and energetic efficiencies in Sparus aurata larvae were investigated. Dry weights and 21 total lengths at day 15 after hatching were similar in larvae fed with 10 and 1 rotifer ml but 21 were significantly higher than in larvae fed with 0.1 rotifer ml . These differences were a consequence of ...

A study was carried out in restored South West Lake and non-restored East Lake, of Beira lake with the objective of determining the species composition, density and distribution of zooplankton. Water was sampled from the surface and at a depth of 1 m, from February to March, 2005 between 0900-1130 h. Three rotifers species; Brachinonus calyciflorus, Keratella tropica, Filinia sp., three cladoce...

Changes in the density and species composition of planktonic rotifers as well as their relationship to several environmental variables were studied at Dadian Lake, a shallow subtropical lake, which was completely dredged and reconstructed. Samples were taken monthly (2006-2009) at five stations. The total rotifer abundance exponentially declined and reached a relatively stable stage in 2009. Po...

We studied whether the effects of Bythotrephes longimanus, a new predatory cladoceran zooplankton species to North America, can extend beyond the macrozooplankton to the rotifer community, which is known to be an important controller of the microbial loop. During summer 2003, 14 Canadian Shield lakes were sampled biweekly to evaluate the effect of Bythotrephes on epilimnetic rotifers. Rotifer d...

Using rotifer-algal microcosms, we tracked rapid evolution resulting from temporally changing natural selection in ecological predator-prey dynamics. We previously demonstrated that predator-prey oscillations in rotifer-algal laboratory microcosms are qualitatively altered by the presence of genetic variation within the prey. In that study, changes in algal gene frequencies were inferred from t...

Little information is known about bioaccumulation of atrazine or the effects it has on consumers that ingest atrazine-contaminated prey. For that reason, freshwater microalgae Chlorella vulgaris cultures were exposed to different concentrations of atrazine for twenty-four hours and were then used as an exclusive food source for Brachionus calyciflorus for three days with the intent to evaluate ...

Members of the ciliate group of protozoans are often observed in mass cultures of rotifers. In particular, Euplotes and Vorticella are common contaminating species. In this study, I examined the effect of the ciliates Euplotes sp. and Vorticella sp. on the growth of the rotifer Brachionus rotundiformis by conducting inter-specific and tripartite-specific mixed-culture experiments. The growth of...

Using the marine rotifer Brachionus plicatilis acute toxicity tests, we estimated the toxicity of Corexit 9500A(®), propylene glycol, and Macondo oil. Ratios of 1:10, 1:50 and 1:130 for Corexit 9500A(®):Macondo oil mixture represent: maximum exposure concentrations, recommended ratios for deploying Corexit (1:10-1:50), 1:130 the actual dispersant:oil ratio used in the Deep Water Horizon spill. ...

1. Compared with rivers in more humid, forested ecoregions of eastern and midwestern U.S.A., rivers in semi-arid grassland of the U.S. Great Plains tend to be relatively shallow, more variable in discharge, and characterised by high suspended sediment loads. Although critical life stages of fish in prairie rivers probably depend at least partially on zooplanktonic food, data on community and di...

The growth and development of marine fish larvae fed copepods is superior to those fed rotifers, but the underlying molecular reasons for this are unclear. In the following study we compared the effects of such diets on redox regulation pathways during development of Atlantic cod (Gadus morhua) larvae. Cod larvae were fed a control diet of copepods or the typical rotifer/Artemia diet commonly u...