Sex differentiation process, determination of sexual strategy, and gametogenesis of the annual fish Austrolebias charrua are established. Evidence of histological sex differentiation in an antero-posterior gradient was observed in pre-hatching stages. Sexual strategy corresponds to the "differentiated gonochoric" pattern. Histological analyses of adult gonads showed an asynchronous spawning mod...

The reproductive biology of the coral reef butterflyfish, Chaetodon multicinctus, was investigated by histological examination of gonads sampled over an 18 month period from a shallow inshore population on Oahu, Hawaii . Most gonads developed directly from previously undifferentiated tissue . Ovarian development (the structural formation of lamellae and primary oocytes) was observed in fish >_4...

The greater amberjack Seriola dumerili is a large teleost fish with rapid growth and excellent flesh quality, whose domestication represents an ambitious challenge for aquaculture. The occurrence of reproductive dysfunctions in greater amberjack reared in captivity was investigated by comparing reproductive development of wild and captive-reared individuals. Wild and captive-reared breeders wer...

Background: Mammals utilise an XX/XY system of sex determination in which the Y-linked gene SRY (Sexdetermining region Y) exerts a dominant masculinising influence on sexual development. Sex chromosome homology and comparative sequence studies suggest that SRY evolved from the related SOX3 gene on the X chromosome, although there is no direct functional evidence to support this hypothesis. The ...

The transcriptome of triangle sail mussel Hyriopsis cumingii (Lea) using Illumina paired-end sequencing technology was conducted and analyzed. Equal quantities of total RNA isolated from six tissues, including gonads, hepatopancreas, foot, mantel, gills and adductor muscles, were pooled to construct a cDNA library. A total of 58.09 million clean reads with 98.48 % Q20 bases were generated. Clus...

The sexual plasticity of the gonads is not retained after the completion of sex differentiation in vertebrates, except in some hermaphroditic species. Here, we report that the depletion of estradiol-17β (E2) by aromatase inhibitors (AI) for up to six months resulted in a functional female-to-male sex reversal in sexually-mature adults of two gonochoristic fish species, Nile tilapia and medaka. ...

Alterations have occurred and continue to manifest in the Earth's biota as a result of climate change. Animals exhibiting temperature dependent sex determination (TSD), including sea turtles, are perhaps most vulnerable to a warming of the Earth as highly skewed sex ratios can result, potentially leading to population extinction resulting from decreased male recruitment. Recent studies have beg...

It was the purpose of this study to describe the secondary sex characters and the histological appearance of the gonads, including the associated duct system, of the fish Lebistes reticulatus from birth through differentiation and maturation when subjected to the hormone estradiol. Sixtyfour Lebistes reticulatus were fed 0.125 mg of estradiol, beginning at birth, at intervals of 60 hours. An eq...

Sexual differentiation in birds is controlled genetically as in mammals, although the sex chromosomes are different. Males have a ZZ sex chromosome constitution, while females are ZW. Gene(s) on the sex chromosomes must initiate gonadal sex differentiation during embryonic life, inducing paired testes in ZZ individuals and unilateral ovaries in ZW individuals. The traditional view of avian sexu...