despite two decades of artificial spawning of wild carp (cyprinus carpio) to rehabilitate natural populations in the southeastern caspian sea, there are still no appropriate physiological criteria for selecting competent brooders during induced spawning. to this end, the plasma concentrations of vitellogenin (vtg), phosphorus (p) and calcium (ca) were measured during ovarian development, as pot...

Indications of effects on fish endocrine system have been noted when exposed to effluents of sewage treatment plants and subsequently in the receiving surface waters. For screening purposes, the concentration of vitellogenin (VTG) in plasma is employed to detect potential exposure of fish, to (anti-)estrogenic substances. However, little is known about the variability of VTG determinations and ...

The expression of the yolk protein vitellogenin (Vtg) has been used as a biomarker of feminisation in multiple fish species throughout the world. Since the late 1990s, researchers have attempted to develop similar biomarkers to address whether reproductive endocrine disruption also occurs in the males of invertebrate groups such as the Crustacea. To date, the vast majority of studies investigat...

Vitellogenin (vtg) is a precursor of the yolk proteins lipovitelline and phosvitin and is synthesized as a consequence of estrogen-dependent gene expression in female and male hepatocytes of egg-laying vertebrates. Freshly isolated carp hepatocytes of a genetically uniform strain of adult male carp (Cyprinus carpio) were used to investigate the effects of primary exposure to estrogenic compound...

An enzyme-linked immunosorbent assay (ELISA) was developed for the detection of the egg yolk precursor vitellogenin (VTG) in the liver of medaka (Oryzias latipes) and was employed to establish an in vivo testing system for estrogen and estrogenic compounds using liver homogenates. Results of 3-month-old fish exposed to three reference chemicals (ethynylestradiol, methyltestosterone and flutamid...

Vitellogenin (VTG) is an egg yolk-precursor protein that serves as a nutrient source for developing embryos in oviparous vertebrates. The hormonal control of this protein has been studied in a variety of taxa, but details about the dynamics of this protein remain to be elucidated in sea turtle species. To investigate the dynamics of VTG in a multi-clutch species under natural conditions, 38 adu...

Vitellogenin (VTG) synthesis in male oviparous vertebrates is used as an indicator of environmental estrogen exposure, but the relationship between elevated VTG levels and the effects of environmental estrogens on reproductive success are poorly understood. To examine whether altered VTG expression predicts reproductive impairment, we exposed medaka (Oryzias latipes) for 2 or 8 weeks posthatch ...

OBJECTIVES Fish vitellogenin (VTG) is produced in the female liver during oogenesis through the estradiol cycle and produced in the male liver by endocrine disrupting chemicals (EDCs) such as alkylphenols. In this study, we propose that the VTG concentration in the pale chub could be detected using monoclonal antibodies and polyclonal antibodies against vitellin (Vn) in a VTG enzyme-linked immu...

An analytical method involving anion exchange high performance liquid chromatographic determination of vitellogenin (Vtg) in fish plasma after postcolumn fluorescence derivatization with o-phthalaldehyde (OPA) was developed. The retention time of Vtg was about 11 min. The reagent variables for derivatization were optimized. The fluorophore was excited at 335 nm and detected at 435 nm. A calibra...

The major component of the animal egg yolk is lipoglycoprotein vitellin, derived from its precursor vitellogenin (VTG), which produced species-specifically in decapod crustaceans hepatopancreas and/or ovary reproductive females. Previous studies on Procambarus clarkii vitellogenesis report existence two single VTGs. Here, a multiple tissue transcriptome including ovaries and P. clarkii, we char...