The interactions between invertebrates and micro-organisms living in streambed sediments often play key roles in the regulation of nutrient and organic matter fluxes in aquatic ecosystems. However, benthic sediments also constitute a privileged compartment for the accumulation of persistent organic pollutants such as PAHs or PCBs that may affect the diversity, abundance and activity of benthic ...

Among spiral cleaving embryos (e.g. mollusks and annelids), it has long been known that one blastomere at the four-cell stage, the D cell, and its direct descendants play an important role in axial pattern formation. Various studies have suggested that the D quadrant acts as the organizer of the embryonic axes in annelids, although this has never been demonstrated directly. Here we show that D ...

Although otolith Strontium (Sr)/calcium (Ca) ratios have been widely used to reconstruct the past salinity environmental history of anguillid eels, factors affecting the Sr/Ca ratios in otoliths are incompletely understood. Japanese Eel (Anguilla japonica) elvers (mean length 54.7±2.1 mm) were collected in the estuary during their upstream migration and reared at 5 different salinities (0, 5, 1...

Myxobolus cerebralis, the myxozoan parasite responsible for whirling disease in salmonids, was first introduced into the United States in 1958 and has since spread across the country, causing severe declines in wild trout populations in the intermountain western United States. The recent detection of the parasite in Alaska is further evidence of the species' capability to invade and colonize ne...

Branchiura sowerbyi (Oligochaeta; Naididae; Rhyacodrilinae) is an oligochaete with great potential to be used as a testspecies in toxicology bioassays. Since 1950, its life cycle has been studied and nowadays it is well described in the literature. B. sowerbyi has a cosmopolitan distribution and can be found in places where Tubifex tubifex (normally used in toxicity bioassays) does not occur, e...

Pyridine, a suspected genotoxic and formaldehyde, a potent carcinogen, are present in several industrial wastewater including commercial solvent, resin and pesticide manufacturing industries. The extent of pyridine and formaldehyde toxicity in aquatic organisms is unknown. Therefore, in present study the toxicity of pyridine and formaldehyde were investigated in artificial aquatic ecosystem (mi...

Monoclonal antibody B4 (mAb B4) was previously developed to the myxozoan parasite Tetracapsuloides bryosalmonae Canning, Curry, Feist, Longshaw et Okamura, 1999, the causative agent of proliferative kidney disease of salmonids, Here we describe the reaction of mAb B4 against Myxobolus cerebralis Hofer, 1903, the parasite that causes 'whirling disease' in salmonids. Tissues examined were collect...