Gonad development and histology in bagrus bayad cultured in. Here we describe a method to produce large numbers of infertile fish by inducing ubiquitous expression of sdf1a in zebrafish embryos resulting in. Select a stage name below to get a detailed description and images. The differentiated gonad g, testis in this image develops from an undifferentiated gonadal anlage, located retroperitoneally in the caudal peritoneal cavity cpc. Zebrafish sex differentiation and gonad development after. Exposure to ee2 125 ngl resulted in a dosedependent increase in vitellogenin production starting at 2 ngl. The gonad begins to form when primordial germ cells and somatic gonad precursor cells coalesce during early development. Deltamethrin is responsible for health and reproduction problems both in mammals and aquatic organisms. The female gonad development of the zebrafish was monitored as four phases according to classification. Oocyte development in the zebrafish, danio rerio teleostei.
Development of bipotential gonads on each side of the embryo,a primitive gonad arises from a genetial ridge,a condensation of tissue near the adrenal gland. Furthermore, the various mutant zebrafish lines arising from such studies would also provide excellent animal models to study the molecular mechanism of gonad development. Mussels were collected throughout the year from the coastal region of the bay of bengal of bangladesh, and the histological analysis. Determination, differentiation and development of the gonads are important processes in early mammalian development. Amh also derives from mature mammalian ovarian follicles, which marks oocyte reserve and characterizes pcos polycystic ovarian syndrome.
Sex determination is the process deciding the sex of a developing embryo. A wave of free cytosolic calcium traverses zebrafish eggs on activation. Ly75, all essential for early gonad development, were targeted with 5 immunization tests. To date no sex linked genes have been identified in zebrafish and no sex chromosomes have been. Gonad development in the female nigerian clarias gariepinus. Early gonad development in zebrafish danio rerio grace emily okuthe 1, shirley hanrahan 2 and barry collins fabian 3 1 department of zoology, walter sisulu university, pbx1 mthatha, 5117.
B and dmale exposed to the mix, presenting a gonad similar to a type i male gonad. For the zebrafish, not much literature on the gonad morphology is available but a lot of literature on toxicity in gonad of zebrafish. Aug, 2014 early gonad development in zebrafish danio rerio grace emily okuthe 1, shirley hanrahan 2 and barry collins fabian 3 1 department of zoology, walter sisulu univer sity, pbx1 mthatha, 5117. Zebrafish sex differentiation and gonad development. Molecular analysis shows differential expression of r. Apr 29, 2014 what happens in a human is we begin our development with the gonads in a fish position. In the female of the species the reproductive cells are the egg cells, and in the male the reproductive cells are the sperm. This book presents the current state of knowledge on the origin and differentiation of cell lines involved in the development of the vertebrate male and female gonads with particular emphasis on the mouse.
The fish can grow up to 10 kg in weight, and considered against the limited scope of choice of culturable fish species available to fish farmers in this region, a better understanding of its cycle of gonad maturation and spawning could help in the domestication of the fish in the lower river niger and beyond. Induced autoimmunity against gonadal proteins affects. Sublethal effects of carbaryl on embryonic and gonadal developments of zebrafish danio rerio article pdf available in african journal of aquatic science 373 november 2012 with 43 reads. Zebrafish is an undifferentiated gonochorous species with a polygenic sex determination system. Control of gonad growth, maturation and spawning in teleost. The zebrafish in toxicologytestis development wikibooks. The posterior lateral line primordium, and underlying structures along the flank of the pharyngula. By fusing zebrafish rspo1 with a green fluorescent protein gene, we found that rspo1 is located in the cytosol and golgi apparatus but not the nucleus of fish epithelioma papulosum cyprinid epc cells. Studies comparing zebrafish fancl homozygous mutants, which develop exclusively as males that produce functional sperm, to dnd knock down animals, which develop as sterile males without sperm, suggested that it is specifically oocyte survival through meiosis, rather than the mere presence of germ cells, which is required for female gonad differentiation in zebrafish rodriguezmari et al. Furthermore, the lack of a genetic sex marker in juvenile zebrafish prevents pooling gonads from. Inducible sterilization of zebrafish by disruption of.
Untill the sixth week of development,these structures are identical in both sexes. These embryos have the great advantage that they develop as see through embryos, that is, all internal development can be clearly observed from the outside in the living embryo. The gonads are formed around the anteroposterior level of somite 10, while the putative attraction center that controls bilateral pgc cluster formation at early somitogenesis is located at the level of. First, lets go over the basic steps in zebrafish development. Fish show a striking plasticity of the sex determination process, which is reflected in a wide range of gonad differentiation mechanisms, and includes gonochoristic species as well as hermaphroditic species. Sex determination process an overview sciencedirect topics. The zebrafish in toxicologytestis development wikibooks, open. Female sex development and reproductive duct formation. Gonad, in zoology, primary reproductive gland that produces reproductive cells gametes.
Native to south asia, it is a popular aquarium fish, frequently sold under the trade name zebra danio and thus often called a tropical fish although both tropical and subtropical. Here, we study the role of the germ cells in somatic development and particularly the role of the germ line in the sex differentiation in zebrafish. The author, who is an acknowledged expert in this subject, has drawn together a wealth of information, providing a book which should be bought by all fish biologists. Morphological development of the gonads in zebrafish, journal. Hardcopies of the 4th edition of the zebrafish book can be obtained for a nominal fee from the zebrafish international resource center, 5274. The importance of germ cells for the feminization of gonads is also reported in the zebrafish, danio rerio slanchev et al. As in other vertebrates, the hpg axis of the neuroendocrine system plays a central regulatory role on the reproductive development of fishes. The structural alterations were observed in the zebrafish oocytes during the oocyte development in the histological studies performed. The first appearance of the gonad is essentially the same in the two sexes, and consists in a thickening of the mesothelial layer of the peritoneum. Integral to this second project is the gathering of biological information which, along with commercial catch and effort data, will be used in the development and interpretation of stock assessment models and in determining how the. It also discusses the processes leading to the testis.
Surface trollcaught fish and subsurface longlinecaught fish are differentiated. Fibroblast growth factor signaling is required for early. An important component of many studies of fish reproductive biology is the assessment of the stage of gonad development of individual fish. In situ hybridization ish targeting transcripts of gsdf, gdf9, and cd205 was performed on sections of 7 monthold zebrafish gonads. Localization of gsdf, gdf9, and cd205 transcripts within the gonad.
By day 10 of zebrafish development, pgcs have condensed with somatic cells to form the gonad primordia braat et al. The majority 97% of the 3536dayold fish showed protogynic ovaries while one out of the 33 fish examined histologically displayed an undifferentiated. Condensing mesenchyme of the early pectoral fin bud. Prim number as a function of hours of development at 28. Pdf sublethal effects of carbaryl on embryonic and. Laser capture microdissection of gonads from juvenile. Zebrafish larva, the stage of development from between three and thirty days postfertilization, grow in length from approximately 3.
Genetic basis and biotechnological manipulation of sexual dimorphism and sex determination in fish. However, the small size of juvenile zebrafish and correspondingly their gonads complicates this type of investigation. Differentiation of gonad tissue in chaetodon multicinctus. Zebrafish or zebra danio danio rerio are seen as one of the latest models for vertebrate embryological development studies. Gonad morphology, histology, and spermatogenesis south. Headtrunk angle as a function of hours of development at 28. Control of gonad growth, maturation and spawning in teleost fish. Gonad development and sex ratio of sharptooth catfish. While the mechanisms of this phenomenon in zebrafish ovaries are not well addressed, here it can be seen in the context of an apoptotic regulation. It has been described as a juvenile hermaphrodite because males undergo a juvenile ovarytotestis gonadal transformation process 46. Aromatase modulation alters gonadal differentiation in. Danio rerio commonly known as the zebrafish is a tropical fish belonging to the minnow family cyprinidae, commonly kept in aquaria and used for scientific research. Gonads are composed of both germ cells and somatic cells that enclose.
Due to the small size and dynamic remodeling of the gonadal tissues in the larval zebrafish, isolation. During gonadal development, the gonad may be transiently intersexual where there is a parallel presence of both oocytes and spermatocytes. The mechanisms controlling zebrafish sex determination and differentiation are not known. Starting with week 5, some fish showed alterations of gonad morphology, including a decrease in the number and size of the oocytes, an enhanced basophilia and irregular shape of the oocytes, and finally their degeneration into. In genital males the medulla develops during seventh and eight.
Transition from nonmotile behaviour to directed migration during early pgc development in zebrafish. The gonads initially develop from the mesothelial layer of the peritoneum the ovary is differentiated into a central part, the medulla, covered by a surface layer, the germinal epithelium. Toxicity of deltamethrin to zebrafish gonads revealed by. A and cfemale exposed to fad, showing a gonad similar to a juvenile ovary. Zebrafish n 5 329 were injected at 6 weeks post fertilization, a booster. Molecular mechanisms of cell differentiation in gonad. The zebrafish and medaka models ebook written by gong zhiyuan, korzh vladimir.
A guide for the laboratory use of zebrafish danio rerio. Jmse free fulltext toxicity of deltamethrin to zebrafish. In this study, the oocyte development of the zebrafish was divided to four stages. The initial formation of the bipotential gonad from uncommitted urogenital ridge requires the function of wilms tumor wt1 and steroidogenic factor. Prior to sex determination, the zebrafish gonad, like the mammalian gonad, is bipotential. Zebrafish is a gonochoristic species, in which each mature individual possesses only ovaries or testes. M any aspects of zebrafish husbandry, including diet, are yet to be standardized. Zebrafish danio rerio is a popular toxicological model and has been used extensively to study the effects of endocrinedisrupting chemicals on gonad development and sexual phenotype 24, 30,31,32, 48,49,50,51,52,53,54,55,56,57. Anatomy of the 24, 48, 72 and 120 hours zebrafish danio rerio embryo this collection of sections through zebrafish embryos at four different stages of development is thought to provide some help to understand how the zebrafish embryo looks inside. B early testis development from previously undifferentiated tissue in a 73 mm sl fish. The zebrafish lifecycle is divided into four major periods.
Author summary the genes involved in the early stages of vertebrate gonad development remain largely undefined. To date, three major developmental pathways were shown to be involved with gonad differentiation through the modulation of programmed cell death. The male gonad, the testicle, produces sperm in the form of spermatozoa. However, their potential in reproductive biology research has yet to be realized. A gonad, sex gland, or reproductive gland is a mixed gland that produces the gametes sex cells and sex hormones of an organism. Dissection of larval zebrafish gonadal tissue ncbi. From gills to gonads, youre more like a fish than you may.
Lam department of zoology, national university of singapore kent ridge, singapore 0511 introduction despite their great variety of reproductive strategies, a general characteristic. For the present study, the histological analysis of gonads in control fish confirmed previous observations that zebrafish is a juvenile hermaphrodite with protogynic gonads, which later develop into ovaries or testes takahashi, 1977, maack and segner, 2003. Zebrafish are an important model species in developmental biology. The early sexual development of zebrafish males is a complicated process, as they first develop a juvenile ovary, that later undergoes a transformation to give way to a testis. Testes are thin and ribbonlike in immature fish, and develop. The roles of amh in zebrafish gonad development and sex. Gonadogenesis in zebrafish goes through an initial ovarian phase then subsequently into either ovarian or testicular phases. Most mutants were female and the few males often had oocytes in their testes, showing that amh promotes male development. Hardcopies of the 4th edition of the zebrafish book can be obtained for a nominal fee from the zebrafish international resource center, 5274 university of oregon, eugene, or 97403 usa. Genetic regulation of mammalian gonad development nature. The full life cycle from fertilized egg to adult is a quick 90 days. Although the reason for this irreversibility is still unknown, one hypothesis has been presented to explain it. The methods for isolation of organs in adult zebrafish such as brain, heart, gonad, and kidney, have been well documented23,24,25.
Effect of lactobacillus rhamnosus use on zebrafish the fish. Starting with week 5, some fish showed alterations of gonad morphology, including a decrease in the number and size of the oocytes, an enhanced basophilia and irregular shape of the oocytes, and finally their degeneration into residual bodies. Download for offline reading, highlight, bookmark or take notes while you read fish development and genetics. An adult zebrafish diet contaminated with chromium reduces. We investigated the chronic effects of deltamethrin on gonads by histopathological examination. The gonadal masculinisation observed in zebrafish following treatment. The zebrafish has become a powerful model and is extensively used in development and diseaserelated research. Furthermore, zebrafish embryos are clear, which allows scientists to watch the fertilized eggs grow into fully formed baby fish under a microscope. Gonad development and vitellogenin production in zebrafish. Apr 01, 2003 morphological development of the gonads in zebrafish morphological development of the gonads in zebrafish maack, g segner, h.
As a reference for normal gonadal development, hematoxylineosin he staining was also performed. Evolution of gonadotropin signaling on gonad development. Exposure to ee2 125 ngl resulted in a dosedependent increase in. The development and maturation of fish gonads are controlled by genetic and environmental factors, and regulated by a molecular network of signals. Feeding protocols vary widely between facilities and can include a combination of live feed andor commercially formulated fish food. Gonad differentiation in zebrafish is regulated by the. Jul 22, 2010 zebrafish has become an important model for understanding vertebrate development and human disease, yet the genetic mechanisms that regulate gonad fate to determine zebrafish sex remain elusive.
Gonadal development in fish fulltext sexual development 2014. The zebrafish is an important and widely used vertebrate model organism in scientific research, for example in drug development, in particular preclinical. Gonadosomatic index which is an index of gonad size relative to fish size is a good indicator of gonadal development in fish 2 the percentage of body weight of fish that is used for production of eggs is determined by the gonadosomatic index. Then, gfp expression increased in early differentiated female at 30 and 35 dpf to reach a high gfp intensity. In this work, we describe a mutation in the fancl gene that causes zebrafish to develop exclusively as male due to femaletomale sex reversal. These cells then migrate toward the gonad where they differentiate into sperms and eggs. Gonad type percentage of 10 zebrafish from control c and probiotic p groups at 3, 6 and 9 weeks post fertilization wpf. Pdf gonadogenesis in zebrafish goes through an initial ovarian phase then subsequently into either ovarian or testicular phases. Sexual differentiation, gonad development, and spawning. In this study, zebrafish adults were exposed for 15 days to 0. During zebrafish development, a gradient of stromalderived factor 1a sdf1a provides the directional cue that guides the migration of the primordial germ cells pgcs to the gonadal tissue.
A early ovary development from previously undifferentiated tissue in a 44 mm sl fish. Danio rerio, gonad, mitoticmeiotic transition, development, sex inversion. Use of transgenic reporter lines combined with histological analysis revealed a variation among males in the onset of transformation. Pdf early gonad development in zebrafish danio rerio. Gonad development was determined histologically by light microscopy. This differential expression may indicate that rspo1 has a roles in zebrafish gonad development and differentiation. The development of the gonads is part of the prenatal development of the reproductive system and ultimately forms the testes in males and the ovaries in females. Biology free fulltext reproductive biology and ecology. Further development of the gonads in female zebrafish up to week 11 pf was characterized by an increase in gonad size as well as in the number and size of perinucleolar oocytes. In fact, in zebrafish some experimental data showed that during ovarian. The zebrafish in toxicologyovary development wikibooks.
Zebrafish is classified as an undifferentiated gonochoristic species yamamoto, 1969. For example, by employing the lhb zebrafish mutant, we have recently demonstrated a factor called insulinlike growth factor 3 as one of the mediators of lh signaling in. Immature reproductive tissue that has not undergone final maturation into either testis or ovary. Investigating gonadal gene expression is important in attempting to elucidate the molecular mechanism of sex determination and differentiation in the model species zebrafish.
However, we know little about the signaling events that lead to the subsequent morphogenesis of the early developing gonadal primordium. Saka ba, adeyemo ok 2015 gonad development in the female nigerian clarias gariepinus burchell 1822. The zebrafish ovary was composed of germ cells at various stages of developmental advancement. Gonad development an overview sciencedirect topics.
Genes determining development of the bipotential gonad the gonad is bipotential, capable of forming either a testis or an ovary until about the sixth week of gestation. Reproductive studies of the fishes require knowledge of the stage of the gonad development in the teleosts. Abundance of early embryonic primordial germ cells. Cycle of gonad maturation, condition index and spawning of. In females, they descend to the level of the uterus. It is closely associated with the peritoneum between arrows. The zebrafish information network zfin is the database of genetic and genomic data for the zebrafish danio rerio as a model organism. The inhibition of apoptosis is therefore crucial to the development of the ovary. You can also browse the zebrafish anatomical ontology ao to show anatomical terms that are present at that stage.
The thick plate of epithelium extends deeply, pushing before it the mesoderm and forming a distinct projection. C spermatogenic crypt formation within lamellae of immature ovary from a 67 mm sl fish. The progenitors of the gametes, the primordial germ cells pgcs are typically specified early in the development in positions, which are distinct from the gonad. This image represents an early previtellogenic stage in ovary development, with predominant occurrence of early oocyte stages i. Fibroblast growth factor signaling is required for early somatic gonad. Developmental biology, issue 122, dissection, gonads, sex determination, larval zebrafish, immature ovary, immature testis. Fish sex could be easily determined in adults by examining. The zebrafish is the most important fish model in developmental and genetic analyses. Zebrafish early gonad development and sex determination. A multidisciplinary approach was applied to explore deeper knowledge about the reproductive biology and ecology of the green mussel perna viridis by interlinking among ecological factors, ingested gut plankton, gonad fatty acid profile, and reproductive traits. The process whose specific outcome is the progression of the male gonad over time, from its formation to the mature structure. Gonad and body mass were measured to the nearest 0. Dissection of larval zebrafish gonadal tissue protocol.