The expression of the vitellogenin gene of the red-claw crayfish Cherax quadricarinatus (CqVg) was previously demonstrated in male crayfish during an endocrinologically induced molt cycle. The hypothesis that this expression is under the direct control of ecdysteroids was tested in this study both in vivo and in vitro. Unlike vitellogenin of insects, CqVg was not found to be ecdysteroid-respons...

Bioavailable calcium is maintained by some crustaceans, in particular freshwater crayfish, by stabilizing amorphous calcium carbonate (ACC) within reservoir organs--gastroliths, readily providing the Ca(2+) needed to build a new exoskeleton. Despite the key scientific and biomedical importance of the in situ molecular-level picture of biogenic ACC and its stabilization in a bioavailable form, i...

Gastroliths are transient extracellular calcium deposits formed by the crayfish Cherax quadricarinatus von Martens on both sides of the stomach wall during pre-molt. Gastroliths are made of a rigid chitinous organic matrix, constructed as sclerotized chitin-protein microfibrils within which calcium carbonate is deposited. Although gastroliths share many characteristics with the exoskeleton, the...

Quantifying the impacts of invasive species, relative to native analogues, is crucial for management and policy development. Two freshwater crayfish species global concern, Cherax quadricarinatus Procambarus clarkii , have established populations across Africa. Negative on biodiversity socioeconomic been documented in other continents; however, there a paucity information from Africa C. . To fi...

Experimental work has been carried out to optimize the feeding conditions and keeping of red claw crayfish in a recirculation aquaculture system (RAS) increase growth during artificial cultivation determine design standards. The lack functional complete feed methodological approaches maintenance necessitated developing effective methods for practical implementation technology minimizing impact ...