The aim of this study was to test the effect of food quantity on energy storage and defense capacities of oysters during a reproductive cycle. One-year-old Crassostrea gigas oysters were fed two different dietary rations (4% and 12% of oyster dry weight in algal dry weight per day) in controlled experimental conditions over an annual cycle. Oyster dry weights, carbohydrate and lipid contents, e...

The widespread use of the herbicide atrazine has incited much research on its toxicity in aquatic systems where it is routinely detected due to runoff from cultivated fields. Moreover, the determination of the genotoxic effect of such pollutants in the marine environment has become a major requirement for ecosystem protection. In the Pacific oyster, Crassostrea gigas, hypodiploid aneuploid cell...

The search for exotic pathogens related to the outbreaks and in surveillance samplings of the Mexican oyster farms, is a recent activity achieved by academic institutions and state committees for Aquatic Animal Health, with remarkable results. In samples of Crassostrea gigas collected through December 2009, January 2010 and November 2010, and of C. corteziensis in September 2011, the protozoan ...

Invertebrates lack canonical adaptive immunity and mainly rely on innate immune system to fight against pathogens. The phagocytes, which could engulf and kill microbial pathogens, are likely to be of great importance and have to undertake significant roles in invertebrate immune defense. In the present study, flow cytometry combined with histological and lectin staining was employed to characte...

Ce is a potential antagonist of Cd due to their similar ionic radius. Its effect on the bioaccumulation of Cd in pacific oyster Crassostreagigaswas explored through laboratory experiments. The oysters were exposed to 5, 10 and 25 μmol/LCe(NO3)3 in the presence of 25 μg/L Cd 2+ (0.22 μmol/L) for 12 days and the concentrations of Cd, Ca, Zn as well as Cu were indicated in the whole soft tissues a...

The hemolymph of oyster Crassostrea belcheri was found to possess significant antibacterial activity against Vibrio harveyi, V. vulnificus and V. cholerae. Hemolymph was partially purified by gel filtration chromatography on Sephacryl S-200 and fractioned into four parts: P1, P2, P3 and P4. The P3 showed the highest antibacterial activity against V. parahaemolyticus, V. cholerae, V. alginolytic...

We compared the temporal dynamics of gametogenesis in diploid and triploid Pacific oysters (Crassostrea gigas) using histology. Oysters were reared in an estuarine farming site in Brittany over 3 years and their gametogenesis was monitored over the exceptionally hot summer of 2003. Both diploids and triploids showed active gametogenesis, but a high proportion of triploids remained at early stag...

In the Pacific oyster, spermatozoa are characterized by a remarkably long movement phase (i.e., over 24 h) sustained by a capacity to maintain intracellular ATP level. To gain information on oxidative phosphorylation (OXPHOS) functionality during the motility phase of Pacific oyster spermatozoa, we studied 1) changes in spermatozoal mitochondrial activity, that is, mitochondrial membrane potent...