11 research outputs found
Identification of Reproduction-Specific Genes Associated with Maturation and Estrogen Exposure in a Marine Bivalve Mytilus edulis
Background: While it is established that vertebrate-like steroids, particularly estrogens (estradiol, estrone) and androgens (testosterone), are present in various tissues of molluscs, it is still unclear what role these play in reproductive endocrinology in such organisms. This is despite the significant commercial shellfishery interest in several bivalve species and their decline. Methodology/Principal Findings: Using suppression subtraction hybridisation of mussel gonad samples at two stages (early and mature) of gametogenesis and (in parallel) following controlled laboratory estrogen exposure, we isolate several differentially regulated genes including testis-specific kinases, vitelline lysin and envelope sequences. Conclusions: The differentially expressed mRNAs isolated provide evidence that mussels may be impacted by exogenous estrogen exposure
Purification of Multiple Precursors for Egg Chorion Proteins in Atlantic Cod ( Gadus morhua
Identification of the Herbicide Surflan and Its Active Ingredient Oryzalin, a Dinitrosulfonamide, as Xenoestrogens
Histological characteristics of the oocyte chorion in wild post-spawning and artificially matured Japanese eels Anguilla japonica
Mother-Specific Signature in the Maternal Transcriptome Composition of Mature, Unfertilized Zebrafish Eggs
Differentiation of Human Embryonic Stem Cells to Cardiomyocytes for In Vitro and In Vivo Applications
Broodâstock management and early hatchery rearing of Arctic charr (Salvelinus alpinus (Linnaeus))
Arctic charr (Salvelinus alpinus (Linnaeus)) is a stenothermic coldâwater fish, which has been cultured in Northern Europe and North America since the 1980s. The industry has remained relatively small with an annual production between 6000 and 10 000 tonnes, and is still challenged by an unreliable offspring production. This review focuses on offspring production in Arctic charr aquaculture including holding conditions for broodâstock, fertilisation and egg rearing until hatch. Broodâstock requires low temperatures during summer (<12°C) with the optimum still unknown. The temperature maximum for egg incubation lies between 6 and 8°C. The composition of an optimal broodâstock diet is debated regarding fatty acids. A demand for a freshwaterâbased diet rich in omegaâ6 fatty acids is indicated, but results remain inconclusive. Extensive knowledge has been gained on the timing of spawning and its manipulation through photoperiod, temperature and hormone treatments; spawning can be induced by shortâday photoperiod; and temperature drops to 5°C. Eggs are fertilised dry in ovarian fluid. Egg quality is highly variable and positively related to egg size and energy density. Contrary, little information is available on sperm quality and its impact on egg survival. There may also be profound differences between Arctic charr of stationary or anadromous origin regarding requirements for holding conditions of broodâstock and their diet. However, these differences have received little attention, and direct comparative studies are in demand