Reduction and methylation of inorganic mercury in Porcellio scaber (Isopoda, Crustacea) and its environment were studied, using a purpose-built experimental setup where Hg cycling was followed using 203Hg2+ tracer in experiments without and with isopods. In experiment without isopods, daily reduction of 203Hg2+ to 203Hg0 under sterile and nonsterile conditions was measured for three weeks to as...

Objective: The potential of marine crabs as a source of bioactive products is largely unexplored. Methods: Portunussegnis crabs were collected from the northern coast of Persian Gulf. Antimicrobial activities of hepatopancreas, hemolymph and proteins of hemplymph from P. segnis crabs against a range of 11 different bacterial and 6 fungal pathogen strains were examined. Two positive controls Amo...

The discontinuous pattern of crustacean cuticular mineralization (the molting cycle) has emerged as a model system to study the spatial and temporal regulation of genes that code for Ca2+-transporting proteins including pumps, channels and exchangers. The plasma membrane Ca2+-ATPase (PMCA) is potentially of significant interest due to its role in the active transport of Ca2+ across the basolate...

Handling of electrolytes and acidic equivalents by the antennal gland was monitored in freshwater crayfish (Pacifastacus leniusculus) during control normoxia (Po 2 = 148mmHg; 1 mmHg = 133-3Pa), 72h of hyperoxia (Po2 = 500mmHg) and 24 h of recovery. A preparation was developed for direct collection of urinary flow (UFR) which was confirmed using inulin clearance (CIN). Renal effluxes of Na + , C...

We investigated the regulation of free radical metabolism in Helix aspersa snails during a cycle of 20-day estivation and 24-h arousal in summer in comparison with estivation/arousal in winter-snails. In winter-snails (J. Exp. Biol. 206, 675-685, 2003), we had already observed an increase in the selenium-dependent glutathione-peroxidase (Se-GPX) activity in foot muscle and hepatopancreas and in...

An aluminum smelter situated at the head of Kitimat Arm (BC, Canada) has discharged polycyclic aromatic hydrocarbons (PAHs) into the receiving waters since 1954. The purpose of the present study was to examine the distribution of PAHs contaminants in dungeness crabs (Cancer magister) collected in Kitimat Arm and Douglas Channel (BC, Canada) by determining the concentrations of PAHs in the hepat...

This study aimed to quantify the accumulation and elimination of Enrofloxacin (ENRO) and Ciprofloxacin (CIPRO) in cultivated Litopenaeus vannamei under controlled laboratory and farm conditions. Laboratory- and farm-raised shrimp were given feed supplemented with 200 mg/kg ENRO for 14 days, followed by a 16-day diet without antibiotics. The levels of ENRO and CIPRO were analyzed by High Perform...

The toxic effect of the dinoflagellate Prorocentrum lima on juvenile American whiteleg shrimp Litopenaeus vannamei and giant lion-paw scallop Nodipecten subnodosus was evaluated. Organisms were exposed to three densities (500, 2000, or 5000 cells mL(-1)), superoxide dismutase activity and soluble protein in the hepatopancreas and muscle were determined at 1, 6, 24 and 48 h after challenge. Shri...