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1
Linhartová, Z., M. Havelka, M. Pšenička, and M. Flajšhans. "Interspecific hybridization of sturgeon species affects differently their gonadal development." Czech Journal of Animal Science 63, No. 1 (December 4, 2017): 1–10. http://dx.doi.org/10.17221/37/2016-cjas.
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Gonad development in fish is generally assumed to be negatively influenced by interspecific hybridization, resulting in sterility or sub-sterility. However, this is not the case in sturgeons (Acipenseridae), in which fertile hybrids are common. In the present study, we investigated gonad development in several sturgeon interspecific hybrids and purebred species. Six interspecific hybrid groups and three purebred groups were analyzed including 20 hybrid specimens with even ploidy, 40 specimens having odd ploidy levels, and 30 purebred specimens. Hybrids of species with the same ploidy (even ploidy – 2n, 4n) exhibited normally developed gonads similar to those seen in purebred specimens. In contrast, hybrids of species differing in ploidy (odd ploidy – 3n) did not display fully developed gonads. Ovaries were composed of oocytes or nests of differentiating oocytes that ceased development in early stages of meiosis (pachytene to zygotene) with a higher content of adipose and apoptotic tissue. Testes contained single spermatogonia along with Sertoli cells and spaces lacking germ cells. The obtained results showed that gonad development was influenced by genetic origin and ploidy of the sturgeon hybrids and were consistent with full fertility of hybrids with even ploidy. Sterility of females, but possibly limited fertility of males, is suggested for hybrids with odd ploidy.
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Lin, Feng, Konrad Dabrowski, and Lucy P. M. Timmermans. "Early gonadal development and sexual differentiation in muskellunge (Esox masquinongy)." Canadian Journal of Zoology 75, no. 8 (August 1, 1997): 1262–69. http://dx.doi.org/10.1139/z97-149.
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Primordial germ cells (PGCs) were first identified in muskellunge (Esox masquinongy) of 14 mm total length (TL) 3 weeks post fertilization. At 32 mm TL, gonad strings were complete and formed a typical gonad shape in cross section. Blood vessels were first found in the gonads with Crossmon staining at 46 mm TL. Some of the PGCs underwent mitotic division at this stage. The ovarian sac started to develop in a fish of 82 mm TL, while the germ cells were still considered to be undifferentiated. In a fish of 138 mm TL, female gonads could be clearly identified from the ovarian sac and groups of oogonia, whereas in another type of gonad, the morphology of undifferentiated gonads was maintained. Germ cells became numerous in both sexes at 211 mm TL. Female gonads contained lobes with germ cells, including oogonia, early-prophase oocytes, and large oocytes. Spermatogonia and cells undergoing mitosis were observed in the testis. Ovaries in a fish of 250 mm TL were at the early stage of perinucleolus (early diplotene). Our observations indicate that in muskellunge (i) the PGCs remained in a resting state for up to 8 weeks post fertilization, (ii) gametogenesis occurred earlier in females than in males, (iii) the gonads developed from an undifferentiated stage directly into an ovary or testis, and (iv) the somatic elements in the gonads differentiated prior to the germ cells.
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Parker, L. E., S. Culloty, R. M. O'Riordan, B. Kelleher, S. Steele, and G. Van der Velde. "Preliminary study on the gonad development of the exotic ascidian Styela clava in Cork Harbour, Ireland." Journal of the Marine Biological Association of the United Kingdom 79, no. 6 (December 1999): 1141–42. http://dx.doi.org/10.1017/s0025315499001472.
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The reproductive cycle, development and spatial organization of the gonads of an exotic ascidian, Styela clava, were studied in Cork Harbour, Ireland. Monthly histological samples enabled the division of gonad development into six main stages, ranging from `inactive' to `regression'. Gonad development was asynchronous in the population, with more than one stage being found within some months. Gametogenesis was observed from February–November, but peaked between August–October. Spawning took place in September–October, followed by gonad regression in November–December.
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Young, P. C., G. J. West, R. J. McLoughlin, and R. B. Martin. "Reproduction of the commercial scallop, Pecten fumatus, Reeve, 1852 in Bass Strait, Australia." Marine and Freshwater Research 50, no. 5 (1999): 417. http://dx.doi.org/10.1071/mf98149.
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To examine the reproduction of Pecten fumatus Reeve, 1852, samples were taken monthly from beds off King Island and in Banks Strait, from July 1986 to July 1987. For each sample the mean gonad-free tissue weight and standardized gonad weight were calculated. The percentage of the sample with each of five macroscopically determined reproductive stages was also measured. Changes in the proportion of cell types within the ovarian part of the gonad were determined by histological and stereological methods. A seasonal cycle of gonadal development occurred at each site, commencing at the time of lowest water temperatures and highest nutrient concentrations. This development progressively increased as the nutrient concentrations declined. No correlation was seen between chlorophyll a and gonad condition. A synchrony in gonad condition was present among individuals in samples; this was greatest at Banks Strait where gonads were larger, and phosphate, nitrate and silicate concentrations were significantly greater. There was no reduction in somatic tissue weight with increase in gonad tissue weight. Maximum gonad development preceded spatfall at each site by about one month.
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Faizah, Ria, and Budi Iskandar Prisantoso. "BIOLOGI REPRODUKSI TUNA MATA BESAR (Thunnus obesus) YANG TERTANGKAP DI SAMUDERA HINDIA." BAWAL Widya Riset Perikanan Tangkap 3, no. 2 (February 7, 2017): 129. http://dx.doi.org/10.15578/bawal.3.2.2010.129-137.
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Tujuan penelitian ini adalah untuk mendapatkan informasi mengenai aspek reproduksi ikan tuna mata besar (Thunnus obesus) di perairan Samudera Hindia. Sebanyak 42 contoh gonad dari ikan tuna mata besar yang tertangkap perairan Samudera Hindia antara bulan Maret sampai Oktober 2008 digunakan dalam penelitian ini. Pengamatan meliputi struktur morfologi gonad ikan, perkembangan gonad, diameter telur, dan fekunditas. Hasil penelitian ini menunjukan bahwa ikantuna mata besar yang tertangkap memiliki tingkat kematangan gonad I, II, dan IV. Nilai gonado somatic index rata-rata tuna mata besar semakin meningkat seiring dengan meningkatnya tingkat kematangan gonad. Musim pemijahan untuk tuna mata besar diduga terjadi pada bulan Oktober. Tuna mata besarmemiliki fekunditas antara 8.163.715-10.365.317 butir dan memiliki pola pemijahan berganda. The objective of this research is to study the reproductive biology of big eye tuna (Thunnus obesus) from Indian Ocean. A numbers of 42 gonad samples were taken from fresh individuals captured in the Indian Ocean during period of March until October 2008. The observation comprised of morphological structure of gonad, gonad development, oocytes diameter, and batch fecundity. The results showed that the gonad maturity stages of big eye tuna were ranged from immature (the gonad maturity stage of I and II) to mature (the gonad maturity stage of IV), and the gonado somatic index value increase along with increase of gonad maturity. Spawning season for big eye tuna estimated was in October, range of fecundity were 8.163.715-10.365.317 oocytes, and the spawning type waspartial spawned.
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Castiglioni, Daniela da Silva, Maria Lucia Negreiros-Fransozo, Laura S. López Greco, Aron F. Silveira, and Sérgio O. Silveira. "Gonad development in females of fiddler crab Uca rapax (Crustacea, Brachyura, Ocypodidae) using macro and microscopic techniques." Iheringia. Série Zoologia 97, no. 4 (December 2007): 505–10. http://dx.doi.org/10.1590/s0073-47212007000400022.
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The morphology of the ovaries in Uca rapax (Smith, 1870) was described based on macroscopic and microscopic analysis. Females were collected in Itamambuca mangrove, Ubatuba, state of São Paulo, Brazil. In the laboratory, 18 females had their ovaries removed and prepared for histology. Each gonad developmental stage was previously determined based on external and macroscopic morphology and afterwards each stage was microscopically described. The ovaries of U. rapax showed a pronounced macroscopic differentiation in size and coloration with the maturation of the gonad, with six ovarian developmental stages: immature, rudimentary, developing, developed, advanced and spent. During the vitellogenesis, the amount of oocytes in secondary stage increases in the ovary, resulting in a change in coloration of the gonad. Oogonias, primary oocytes, secondary oocytes and follicular cells were histologically described and measured. In female’s ovaries of U. rapax the modifications observed in the oocytes during the process of gonad maturation are similar to descriptions of gonads of other females of brachyuran crustaceans. The similarities are specially found in the morphological changes in the reproductive cells, and also in the presence and arrange of follicle cells during the process of ovary maturation. When external morphological characteristics of the gonads were compared to histological descriptions, it was possible to observe modifications that characterize the process in different developmental stages throughout the ovarian cycle and, consequently, the macroscopic classification of gonad stages agree with the modifications of the reproductive cells.
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Tarsim, M. Zairin Junior, and E. Riani. "Effect of Estradiol-17β Injection on Gonad Development of White Shrimp (Litopenaeus vannamei)." Jurnal Akuakultur Indonesia 6, no. 1 (January 1, 2007): 17. http://dx.doi.org/10.19027/jai.6.17-25.
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<p>The methods for hormonal control of shrimp reproduction are very limited, and only eyestalk ablation is used to induce ovarian development and spawning in shrimp farming. The occurrence of vertebrate-type steroid hormones in crustaceans have been reported, however, their physiological role are not sufficiently understood. The present study analyzed the effect of estradiol-17β injection on gonad development of white shrimp, <em>Litopenaeus vannamei</em>. The estradiol-17β dose 0.10 μg/g body weight were used. The treatments consisted of control, single injection (day 0) and double injection (day 0 and 6). The females broodstock were cultured for 12 days. The result showed that estradiol-17β had positive effect on gonad development. The gonado somatic index (GSI) and oocytes diameter in treatment larger than the control. Double injection had highest effect with ∆GSI and oocytes diameter was 0.453<sup> </sup> and 23.97 µm, respectively. The only oocytes previtelogenesis was found in gonad. It indicated that estradiol-17β important to induce endogenous vitellogenesis. Gonad development probably affected by gonad inhibiting hormone in the eyestalk. It was inhibited oocyte maturation. The polypeptide sub unit was observed in vitellin of ovari by SDS-PAGE. The molecular weights of approximately 95, 98, 109 and two units higher than 118 kDa of protein marker.</p> <p>Keywords: Gonad, estradiol-17β, oocyte, <em>Litopenaeus vannamei</em></p> <p> </p> <p>ABSTRAK</p> <p>Teknologi reproduksi dalam pembenihan udang belum mengalami perkembangan yang signifikan. Pada umumnya untuk mempercepat kematangan gonad induk udang digunakan teknik ablasi. Mekanisme dan peranan hormon pada proses reproduksi udang belum banyak diketahui. Keberadaan hormon steroid pada krustase telah dikemukaan oleh beberapa peneliti, tetapi peranannya belum banyak diketahui. Pada penelitian ini dikaji pengaruh penyuntikan hormon estradiol-17β pada perkembangan gonad induk udang putih (<em>Litopenaeus vannamei</em>). Penelitian ini menggunakan dosis 0,10 μg/g bobot tubuh dengan perlakuan penyuntikan tunggal (hari ke-0) dan ganda (hari ke-0 dan ke-6). Sebagai pembanding dilakukan uji tanpa perlakuan (kontrol). Untuk melihat respon perkembangan gonad, pemeliharaan induk dilakukan selama 12 hari. Hasil penelitian menunjukkan bahwa estradiol-17β berpengaruh positif pada perkembangan gonad. <em>Gonado somatic index </em>(GSI) dan rata-rata diameter oosit pada perlakuan relative lebih tinggi dibandingkan kontrol. Penyuntikan ganda memberikan pengaruh paling besar dengan peningkatan GSI sebesar 0,453<sup> </sup> dan rata-rata diameter oosit 23,97 µm. Oosit pada gonad hanya mampu berkembang hingga tahap previtelogenesis. Hal ini menunjukkan bahwa estradiol-17β berperang dalam vitelogenesis endogenous. Keberadaan hormon penghambat perkembangan yang dihasilkan tangkai mata diduga menyebabkan oosit tidak dapat mencapai matang. Analisis SDS-PAGE menunjukkan bahwa protein kuning telur pada gonad terdapat 5 sub unit dengan perkiraan bobot 95, 98, 109 kDa dan dua unit >118 kDa.</p> <p>Kata kunci: Gonad, estradiol-17β, oosit, <em>Litopenaeus vannamei</em></p>
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Vives, Ailet, Tamara Rubilar, María-Dinorah Herrero-Pérezrul, and Bertha-Patricia Ceballos-Vázquez. "Reproduction of the sea urchin Tripneustes depressus (Camarodonta: Toxopneustidae) in Bahía de La Paz, Baja California Sur, Mexico." Revista de Biología Tropical 69, Suppl.1 (March 23, 2021): 202–18. http://dx.doi.org/10.15517/rbt.v69isuppl.1.46353.
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Introduction: Sea urchin gonads (roe or uni) are considered a culinary delicacy worldwide. However, only a few species are considered edible and commercialized. The sea urchin Tripneustes depressus has generated the interest of producers in Baja California Sur, Mexico, due to the quality of its gonads. A biological basis for designing a management strategy is key to consider its commercial exploitation. Objective: To determine the reproductive season of T. depressus through description of the gonad stages and reproductive cycle, and to establish its relationship with environmental factors. Methods: We collected monthly samples (October 2016-September 2017), recording in-situ temperature and photoperiod. We evaluated a sample of 1 055 specimens for demographic characteristics, using total weight (g) and test diameter (cm). We also did a histological analysis of gonads from 178 individuals. Results: Average test diameter was 9.70 ± 0.03 cm (5-12.50 cm). Based on the proportion into the gonad of sexual (gametes) and somatic (nutritive phagocytes) cells, we propose five gonad stages (growing, premature, mature, spawning, and intergametic) for both sexes. There were two times of the year when gonads were heaviest and closely corresponded to the growing stage, coinciding with the highest proportions of nutritive phagocytes. Gonad development (growing and premature stages) peaks in the months with the longest daylight periods, with spawning in the shortest daylight periods. Conclusions: Gonad wet weight and adjusted gonad weight are good indicators of the reproductive season of T. depressus. The lowest gonad wet weights were matched the spawning peak in the shortest daylight period (January and March).
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Piprek, Rafal P., Michal Kolasa, Dagmara Podkowa, Malgorzata Kloc, and Jacek Z. Kubiak. "Tissue-specific knockout of E-cadherin (Cdh1) in developing mouse gonads causes germ cells loss." Reproduction 158, no. 2 (August 2019): 149–59. http://dx.doi.org/10.1530/rep-18-0621.
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The normal course of gonad development is critical for the sexual development and reproductive capacity of the individual. During development, an incipient bipotential gonad which consists of unorganized aggregate of cells, must differentiate into highly structured testis or ovary. Cell adhesion molecules (CAMs) are a group of proteins crucial for segregation and aggregation of different cell types to form different tissues. E-cadherin (Cdh1) is one of the CAMs expressed in the developing gonads. We used tissue-specific knockout of Cdh1 gene in OCT4+ germ cells and, separately, in SF1+ somatic cells of developing gonads. The knockout of E-cadherin in somatic cells caused decrease in the number of germ cells, while the knockout in the germ cells caused their almost complete loss. Thus, the presence of E-cadherin in both the germ and somatic cells is necessary for the survival of germ cells. Although the lack of E-cadherin did not impair cell proliferation, it enhanced apoptosis, which was a possible cause of germ cell loss. However, the somatic cells of the gonad differentiated normally into Sertoli cells in the testis cords, and into follicular cells in the ovaries. The testis and ovigerous cords maintained their integrity; they were covered by continuous basement membranes. The testicular interstitium with steroidogenic fetal Leydig cells did not show any noticeable changes. However, in the female gonads, because of the lack of germ cells, the ovarian follicles were absent. The sex determination and sexual differentiation of the gonad were not impaired. These results underscore an important role of E-cadherin in germ cell survival and gonad development.
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Oliveira, MR, NB Silva, ME Yamamoto, and S. Chellappa. "Gonad development and reproduction of the ballyhoo half beak, Hemiramphus brasiliensis from the coastal waters of Rio Grande do Norte, Brazil." Brazilian Journal of Biology 75, no. 2 (May 2015): 324–30. http://dx.doi.org/10.1590/1519-6984.12113.
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The gonad development and reproductive aspects of Hemiramphus brasiliensis from the coastal waters of Rio Grande do Norte, Brazil were verified. This paper presents data on the length-weight relationship, sex ratio, length at first sexual maturity, gonad development, reproductive period and fecundity of H. brasiliensis. Females of this species predominated in the sampled population and were larger in size than the males. The length at the first sexual maturation of males was 20.8 cm and that of females was 21.5 cm. The macroscopic characteristics of the gonads indicated four maturation stages. Histological studies of gonads of H. brasiliensis showed six phases of oocyte development and four phases of spermatocyte development. The batch fecundity of this species is 1153 (±258.22) oocytes for 50 g body weight of female. The microscopic characteristics of gonad development indicate that H. brasiliensis is a multiple spawner, with active reproductive period during the months of January to June and October. The reproductive period of this species is independent of the rainy period of the region.
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Sembiring, Sari Budi Moria, and Jhon Harianto Hutapea. "GONAD DEVELOPMENT OF SANDFISH (Holothuria scabra) FED WITH VITAMIN E-SUPPLEMENTED DIET." Indonesian Aquaculture Journal 14, no. 2 (December 13, 2019): 47. http://dx.doi.org/10.15578/iaj.14.2.2019.47-54.
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The experiment was conducted to evaluate the effect of vitamin E on the gonad development of sandfish, Holothuria scabra. Four experimental diets were formulated to contain different levels of vitamin E, i.e. 0, 150, 300, and 450 mg/kg diet. Dry diets were prepared at the same protein level (14%). The experiment was arranged in a completely randomized design with four treatments and three replicates. Before the experiment started, the internal organs of broodstock were removed (evisceration) by injecting KCl 1 N reagent into their body, and the gonads were observed to determine the sex of each broodstock. Mean total length and body weight of broodstock after the internal organ removal were 10.95 ± 0.37 cm and 61.12 ± 2.28 g, respectively. Three broodstock (one male and two females) were allocated into each plastic bucket with a volume of 150 L. Each plastic bucket was equipped with aeration and flow-through water system. Broodstock fed with experimental diet once daily at 3% of total biomass for 90 days. The results showed that vitamin E has significant effects on percentage of gonad maturation stages and gonad somatic index (GSI) (P<0.05). Vitamin E at 300 mg/kg diet was the best for gonad maturation of sandfish broodstock. Furthermore, 55.5% and 11.1% of broodstock fed a diet containing 300 mg vitamin E/kg diet reached gonad maturity stage-III and stage-IV, respectively, with GSI of 12.21%.
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Barbosa, S. S., M. Byrne, and B. P. Kelaher. "Reproductive periodicity of the tropical intertidal chiton Acanthopleura gemmata at One Tree Island, Great Barrier Reef, near its southern latitudinal limit." Journal of the Marine Biological Association of the United Kingdom 89, no. 2 (March 2009): 405–11. http://dx.doi.org/10.1017/s0025315408002877.
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Reproduction in the pantropical chiton Acanthopleura gemmata was examined at One Tree Island, Great Barrier Reef, near the southern limit of its distribution, using gonad histology and gonad index (GI). Gonad growth was associated with the onset of gametogenesis in mid-spring. Fully mature gonads were present from early summer until late autumn. During these months gametes at various stages of development were present in the gonads indicating a continuous pattern of gamete development and release over the six month spawning season. Following the maximum GI (March/April) there was a sharp drop in the index marking the end of spawning. In winter, the gonads entered a rest period and remained small in size. The reproductive pattern of A. gemmata at its southern limit is similar and 6 months out of phase to that reported for populations in the Gulf of Suez, at the northern limit of its distribution. This suggests that photoperiod may be an important factor in modulating reproduction. Reproduction of A. gemmata at One Tree Island is also similar to that for populations in the northern Great Barrier Reef.
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Campoy-López, Pedro, Estefanía Pereira-Pinto, Leonardo Mantilla-Aldana, and Ricardo Beiras. "Effects of Ethinylestradiol (EE2) and an Organophosphorus Flame Retardant (TCPP) on Gonadal Maturation in the Sea Urchin, Paracentrotus lividus." Journal of Marine Science and Engineering 8, no. 8 (August 16, 2020): 611. http://dx.doi.org/10.3390/jmse8080611.
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The sea urchin (Paracentrotus lividus) was used to test the effects of one of the most abundant flame retardant additives for plastics, tris (1-chloro-2-propyl) phosphate (TCPP), and the synthetic hormone ethinylestradiol (EE2) on gametogenesis and gonad development of adults. With this aim, 403 individuals of both sexes were exposed to TCPP concentrations ranging from 0.2 to 10 µg/L, EE2 (0.01 µg/L), seawater and solvent controls for 7 and 28 days. EE2 and TCPP exposure did not cause histological damage in the gonads. Some evidence of estrogenic effects of TCPP within the µg/L range and EE2 within the ng/L range is reported. Females exposed to 1 µg/L TCPP for 7 days showed a significant increase in gonad development assessed as gametogenic stage, females exposed to 10 µg/L TCPP showed increased gonad development both in terms of weight (Gonad Index, GI, at both 7 and 28 days) and maturation (Pixelar Index, PI), and females exposed to 10 ng/L EE2 showed increased PI after 28 days exposure. Male sea urchins exposed to both TCPP and EE2 for 7 days showed increased frequencies of low development gonad stage. However, the patterns of response are affected by the high inter-individual variability, the differing initial stage of the gonad, as well as the dosage administered.
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Habibah, Aulidya Nurul, Rika P.C. Pertiwi, and Titi Chasanah. "Gonadal Differentiation of Nilem Fish (Osteochilus vittatus) Utilizing Temperature Treatment." BIOEDUSCIENCE 4, no. 2 (December 31, 2020): 143–47. http://dx.doi.org/10.22236/j.bes/425704.
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Background: Gonad differentiation in some teleostei is a critical phase of gonad development. Gonad differentiation in some fish such as the tilapia group is influenced by environmental factors, namely temperature. The aim of this study was to determine the differentiation process of Nilem fish gonads (Osteochilus vittatus) under the influence of temperature. Methods: One day after fertilization (days postfertilization/dpf) fish were exposed to different medium temperature ranges, namely: 28-29 oC, 30-31 oC, 32-33 oC, and room temperature as a control for 35 days. The percentage of fish survival was calculated on the 35th day by calculating the number of surviving fish divided by the total number of fish in 1 tank times 100%. Thirty fish in each treatment were measured for body length at day 10 dpf and day 35 dpf to determine fish growth. Six fish 35 dpf from each treatment were fixed in 70% alcohol for making histological preparations using the paraffin method, Haematoxylin-Eosin staining. Fish survival data growth data in the form of fish length were analyzed using Anova. Gonadal differentiation data were analyzed descriptively. Results: There was no significant difference in the growth of fish in all treatment and control groups. The average survival rate of fish in all treatment and control groups was 100%. Observation of the gonads showed that the gonads were not differentiated in all treatment and control groups. Conclusion: The room temperature range up to 33 oC supports the growth of Nilem fish with gonad development in the indifferent gonad stage.
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Brogger, M. I., M. I. Martinez, and P. E. Penchaszadeh. "Reproduction of the sea urchin Arbacia dufresnii (Echinoidea: Arbaciidae) from Golfo Nuevo, Argentina." Journal of the Marine Biological Association of the United Kingdom 90, no. 7 (June 2, 2010): 1405–9. http://dx.doi.org/10.1017/s0025315410000445.
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Arbacia dufresnii is a common and abundant sea urchin in Argentinean waters. The gonad index cycle was studied for this species in Golfo Nuevo, Patagonia, from May 2001 to March 2003. Comparative studies of gonad index and gonad histology were performed for the three years of 2001, 2002 and 2003. The gonad index reflects gonadal stages, and the results showed two spawning peaks for the studied period. The first spawning event occurred during spring and a second major spawning occurred in summer. Proliferation and differentiation of gametes, and the presence of mature gonads were synchronous among males and females. Male and female individuals spawned synchronically. Gonad resorption was observed for males and females. Histological examination data reflected gonad index analysis, providing together a good estimation of the reproductive cycle of A. dufresnii. Statistical analyses showed a positive correlation between gonad index and photoperiod. The mean fresh oocyte diameter observed was 87.1 µm (SD = 1.3 µm) with a jelly coat of 12.7 µm (SD = 0.9 µm), which corresponds to planktotrophic larval development.
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Bourgoin, A., and M. Guillou. "Variations in the reproductive cycle of Acrocnida brachiata (Echinodermata: Ophiuroidea) according to environment in the Bay of Douarnenez (Brittany)." Journal of the Marine Biological Association of the United Kingdom 70, no. 1 (February 1990): 57–66. http://dx.doi.org/10.1017/s0025315400034196.
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The annual reproductive and somatic cycles of the brittlestar Acrocnida brachiata are described using gonad and gut indices for intertidal and subtidal populations in the Bay of Douarnenez, France. Oocyte size frequency diagrams complement the gonad study in the subtidal population. Clearly marked reproductive cycles are defined in both populations. Accelerated gonad growth takes place in spring and the gonads reach the peak of development in May-June each year. Spawning is completed by the end of August. Oocytes reach a mean diameter of 150 μm and a new generation of oocytes appaears in the ovaries during the spawning period. The gut indices show a clear inverse relationship with the gonad indices in the intertidal population, but this relation is not well revealed in the subtidal population.
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Lucas, Cathy H., and Adam J. Reed. "Gonad morphology and gametogenesis in the deep-sea jellyfish Atolla wyvillei and Periphylla periphylla (Scyphozoa: Coronatae) collected from Cape Hatteras and the Gulf of Mexico." Journal of the Marine Biological Association of the United Kingdom 90, no. 6 (November 3, 2009): 1095–104. http://dx.doi.org/10.1017/s0025315409000824.
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Observations on gonad morphology and the structure of ovaries and testes of the coronate scyphozoans Atolla wyvillei and Periphylla periphylla are described based on samples collected from the Gulf of Mexico and Cape Hatteras (north-western Atlantic). In A. wyvillei, gonads of distinguishable sex were observed in medusae as small as 17 mm bell diameter (BD). Spermatogenesis occurred within follicles (average 366 × 254 μm) that were evenly distributed throughout the gonad. Oocytes in different stages of development were observed in all the females with gonads. Oocytes arise from the gastrodermis and migrate into the mesoglea to develop from early-mid to late vitellogenic oocytes characterized by a large nucleus and granular (organic-rich) cytoplasm. The largest oocytes measured were 543 μm and 263 μm from the Gulf of Mexico and Cape Hatteras respectively. Possible reasons for this difference are discussed. In P. periphylla gonads were also initially observed in medusae 17 mm BD, although not all larger medusae had obvious gonads. Unlike A. wyvillei sperm follicles were arranged in long convoluted rows normally only one follicle thick. The organization of ooytes in female P. periphylla was very similar to A. wyvillei, although the gonads were small and the number of oocytes present in each gonad very low (<22). The largest oocyte measured was 777 μm in a 53 mm BD medusa. Although medusae were collected from one time period only (September) in this study, our findings appear to be in agreement with literature evidence indicating that coronate jellyfish produce few eggs continuously over a long time period. Aspects of gonad development and gametogenesis are discussed with respect to potential differences in site productivity and species identification.
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Koopman, Peter. "Gonad development: Signals for sex." Current Biology 11, no. 12 (June 2001): R481—R483. http://dx.doi.org/10.1016/s0960-9822(01)00287-1.
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Nakabayashi, O., H. Kikuchi, T. Kikuchi, and S. Mizuno. "Differential expression of genes for aromatase and estrogen receptor during the gonadal development in chicken embryos." Journal of Molecular Endocrinology 20, no. 2 (April 1, 1998): 193–202. http://dx.doi.org/10.1677/jme.0.0200193.
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In birds, differentiation of embryonic gonads is not as strictly determined by the genetic sex as it is in mammals, and can be influenced by early manipulation with a sex steroid hormone. Thus administration of an aromatase inhibitor induces testis development in the genetic female, and administration of estrogen induces a left ovotestis in the genetic male embryo. Another feature of avian gonadogenesis is that only the left ovary develops in most species. Molecular mechanisms underlying these features at the level of gene expression have not been elucidated. In this paper, we present evidence that a gene for aromatase cytochrome P-450, an enzyme required for the last step in the synthesis of estradiol-17beta, is expressed in medullae of the left and right gonads of a female chicken embryo, but not in those of a male chicken embryo, and that an estrogen receptor gene is expressed only in epithelium (and cortex later, in the female) of the left, not the right, gonad of both sexes, but the expression in the male left gonad is temporary and restricted to an early stage of development. Differential expression of these two genes serves well to explain the above features of gonadal development in birds. Furthermore, in ovo administration of estradiol-17beta from the 5th to the 14th day of incubation does not cause expression of the estrogen receptor gene in the right gonad of chicken embryos of either sex, suggesting that the absence of expression of the estrogen receptor gene in the right gonad is not the result of down-regulation, but may be regarded as an important cause of the unilateral ovarian development.
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Kasmi, Mauli, Syamsul Hadi, and Wayan Kantun. "Biologi reproduksi ikan kembung lelaki, Rastreliger kanagurta (Cuvier, 1816) di perairan pesisir Takalar, Sulawesi Selatan." Jurnal Iktiologi Indonesia 17, no. 3 (June 25, 2018): 259. http://dx.doi.org/10.32491/jii.v17i3.364.
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The objective of this research is to observe reproductive biology of Indian mackerel in Takalar coastal waters through gonad maturity development, the first size of mature gonad, spawning, gonado somatic index (GSI), and fecundity. Sampling was done for eight months started from March to October 2015. Gonad maturity stage was observed morphologically, spawning season focusing on direct observation result toward gonad by identifying Indian mackerel which has spawned.GSI was analyzed based on comparison between gonad weight and Indian mackerel weight while fecundity was observed by gravimetric method. Analysis result shows that Indian mackerel gonad maturity throughout the year with peak occurring in July and August. GSI was around 0,928-4,490. The first size of gonad mature of female Indian mackerel is 21,18 cm and male Indian mackerel is 21,31 cm. Spawning occurs after peak of gonad maturity so next month, value of maturity index decreases slowly and gradually. Indian mackerel has total fecundity around 11.235- 40.878 granule. AbstrakPenelitian ini bertujuan untuk mengamati biologi reproduksi ikan kembung lelaki di perairan pesisir Takalar melalui perkembangan kematangan gonad, ukuran pertama matang gonad, musim pemijahan, indeks kematangan gonad (IKG), dan fekunditas. Pengambilan sampel dilakukan selama delapan bulan mulai Maret sampai Oktober 2015. Perkembang-an kematangan gonad diamati secara morfologi. Musim pemijahan mengacu pada hasil pengamatan langsung terhadap gonad dengan mendata ikan kembung lelaki yang telah memijah. IKG dianalisis berdasarkan perbandingan antara bobot gonad dan bobot tubuh ikan kembung lelaki, sedangkan fekunditas dihitung dengan metode gravimetrik. Hasil analisis menunjukkan bahwa ikan kembung lelaki mengalami kematangan gonad sepanjang tahun dengan puncak terjadi pada bulan Juli dan Agustus. IKG berkisar 0,928-4,490. Ukuran ikan kembung lelaki betina kali pertama matang gonad adalah 21,18 cm dan jantan adalah 21,31 cm. Pemijahan terjadi setelah puncak kematangan gonad sehingga pada bulan berikutnya terjadi penurunan nilai indeks kematangan secara perlahan dan bertahap. Ikan kembung lelaki memiliki fekunditas total berkisar 11.235-40.878 butir.
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Piprek, Rafał P., Anna Pecio, Jacek Z. Kubiak, and Jacek M. Szymura. "Differential effects of testosterone and 17β-estradiol on gonadal development in five anuran species." REPRODUCTION 144, no. 2 (August 2012): 257–67. http://dx.doi.org/10.1530/rep-12-0048.
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Sex hormones are essential for sexual differentiation and play a key role in the development of gonads in amphibians. The goal of this study was to evaluate the influence of exogenous sex steroids, testosterone, and 17β-estradiol (E2) on development of gonads in five anuran species differing in their evolutionary positions, sex determination, and mode of gonadogenesis. We found that in two closely related species of fire-bellied toad, Bombina bombina and Bombina variegata, testosterone and E2 exposure results in sex reversal as well as intersex and undifferentiated gonads. Similarly, sex reversal was observed in Hyla arborea after exposure to male or female sex steroids. Xenopus laevis was sensitive to E2 but only moderately to testosterone. In Bufo viridis, treatment with either sex hormone provoked a developmental delay in gonads and Bidder's organs. Therefore, susceptibility to hormonal sex reversal appeared species dependent but unrelated to genetic sex determination and the type of gonadogenesis. We also found that the onset of sex steroid exposure influences gonad differentiation and the meiotic status of the germ cells depends on their location within the gonad. Our findings reveal differential sensitivity of amphibians to testosterone and E2, establishing a hierarchy of sensitivity to these hormones among different anuran species.
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Calatayud, Natalie E., Andrew J. Pask, Geoffrey Shaw, Nadine M. Richings, Sue Osborn, and Marilyn B. Renfree. "Ontogeny of the oestrogen receptors ESR1 and ESR2 during gonadal development in the tammar wallaby, Macropus eugenii." REPRODUCTION 139, no. 3 (March 2010): 599–611. http://dx.doi.org/10.1530/rep-09-0305.
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Oestrogen has wide ranging effects in development mediated mainly via the two oestrogen receptors, α (ESR1, also known as ERα) and β (ESR2, also known as ERβ). Oestrogen is the key factor that directs the indifferent gonad to become an ovary in many non-mammalian vertebrates. Oestrogen is not required for early ovarian differentiation in mammals but can disrupt normal testicular development in eutherians. Surprisingly, exogenous oestrogen can cause sex reversal of an XY gonad in two marsupials, the North American opossum and the tammar wallaby. To understand the mechanism by which oestrogen induces sex reversal, we characterised the genes for ESR1 and ESR2 and examined their expression during gonadal differentiation in the tammar wallaby, Macropus eugenii. Both receptors were expressed in the somatic cells and germ cells of the indifferent gonad in both XX and XY foetuses throughout all stages of development, and persisted in these cells into adulthood. ERs were also present in many other tissues including kidney, pituitary and mammary gland. ER mRNA was not significantly altered by exogenous oestrogen in cultured XY gonads but the receptors translocated to the nucleus in its presence. These findings confirm that there is conserved expression of the ERs in the indifferent gonad despite the lack of available ligand during early gonadal development. The receptors can respond to exogenous estrogen at this early stage and are capable of transducing signals in the early mammalian gonad. However, the selective forces that maintained conserved ER expression in this tissue remain unknown.
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Stewart, Melanie K., Deidre M. Mattiske, and Andrew J. Pask. "Exogenous Oestrogen Impacts Cell Fate Decision in the Developing Gonads: A Potential Cause of Declining Human Reproductive Health." International Journal of Molecular Sciences 21, no. 21 (November 8, 2020): 8377. http://dx.doi.org/10.3390/ijms21218377.
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The increasing incidence of testicular dysgenesis syndrome-related conditions and overall decline in human fertility has been linked to the prevalence of oestrogenic endocrine disrupting chemicals (EDCs) in the environment. Ectopic activation of oestrogen signalling by EDCs in the gonad can impact testis and ovary function and development. Oestrogen is the critical driver of ovarian differentiation in non-mammalian vertebrates, and in its absence a testis will form. In contrast, oestrogen is not required for mammalian ovarian differentiation, but it is essential for its maintenance, illustrating it is necessary for reinforcing ovarian fate. Interestingly, exposure of the bi-potential gonad to exogenous oestrogen can cause XY sex reversal in marsupials and this is mediated by the cytoplasmic retention of the testis-determining factor SOX9 (sex-determining region Y box transcription factor 9). Oestrogen can similarly suppress SOX9 and activate ovarian genes in both humans and mice, demonstrating it plays an essential role in all mammals in mediating gonad somatic cell fate. Here, we review the molecular control of gonad differentiation and explore the mechanisms through which exogenous oestrogen can influence somatic cell fate to disrupt gonad development and function. Understanding these mechanisms is essential for defining the effects of oestrogenic EDCs on the developing gonads and ultimately their impacts on human reproductive health.
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Ramofafia, Christain, Maria Byrne, and Stephen Battaglene. "Reproductive biology of the intertidal sea cucumber Actinopyga mauritiana in the Solomon Islands." Journal of the Marine Biological Association of the United Kingdom 81, no. 3 (June 2001): 523–31. http://dx.doi.org/10.1017/s0025315401004179.
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Over a four year period, gonad index, examination of gonad tubules, and histology were used to study the reproduction in the sea cucumber Actinopyga mauritiana. This species reproduced annually during the warmer months of the year in Solomon Islands. This annual reproductive cycle progressed through five maturity stages: recovery, growing, mature, partly-spawned and spent. The recovery stage (March–May) was marked by initiation of gametogenesis and coincided with decreasing day length. The growing stage (June–September) was characterized by development of gametes through to the mature stage (October–December). Spawning occurred October through December and coincided with increased water temperature and day length. Spent gonads (January–March) contained a few unspawned gametes or completely lacked gametes. Although A. mauritiana had annual reproduction, individuals lacking or having indeterminate gonads were present year-round. Macroscopic examination of gonad tubules after biopsy provides a practical tool for assessing maturity condition of broodstock in the field during the reproductive season.
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Piprek, Rafal P., Michal Kolasa, Dagmara Podkowa, Malgorzata Kloc, and Jacek Z. Kubiak. "N-Cadherin Is Critical for the Survival of Germ Cells, the Formation of Steroidogenic Cells, and the Architecture of Developing Mouse Gonads." Cells 8, no. 12 (December 11, 2019): 1610. http://dx.doi.org/10.3390/cells8121610.
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Normal gonad development assures the fertility of the individual. The properly functioning gonads must contain a sufficient number of the viable germ cells, possess a correct architecture and tissue structure, and assure the proper hormonal regulation. This is achieved by the interplay between the germ cells and different types of somatic cells. N-cadherin coded by the Cdh2 gene plays a critical role in this interplay. To gain an insight into the role of N-cadherin in the development of mouse gonads, we used the Cre-loxP system to knock out N-cadherin separately in two cell lines: the SF1+ somatic cells and the OCT4+ germ cells. We observed that N-cadherin plays a key role in the survival of both female and male germ cells. However, the N-cadherin is not necessary for the differentiation of the Sertoli cells or the initiation of the formation of testis cords or ovigerous cords. In the later stages of gonad development, N-cadherin is important for the maintenance of testis cord structure and is required for the formation of steroidogenic cells. In the ovaries, N-cadherin is necessary for the formation of the ovarian follicles. These results indicate that N-cadherin plays a major role in gonad differentiation, structuralization, and function.
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Ibrahim, Yusran, Dinar Tri Soelistyowati, and Odang Carman. "Triploid striped catfish Pangasianodon hypophthalmus: growth performance and gonadal development." Jurnal Akuakultur Indonesia 16, no. 1 (July 5, 2017): 76. http://dx.doi.org/10.19027/jai.16.1.76-82.
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<p><strong>ABSTRACT </strong></p><p> </p><p>This study was aimed to evaluate the growth performance and gonadal development of diploid and triploid striped catfish <em>Pangasianodon hypophthalmus</em>. Triploids were produced through a heat shock method at 42 °C for two minutes, at two minutes after fertilization. Before treatment performed, group of triploid and diploid were separated through nucleolus counting confirmed cromoseme counting. Five individual of each group at the age of nine months were tagged and reared for two months. Parameter of growth performance, feed conversion ratio, and survival rate were analysed using <em>independent-samples t-test </em>at confidence interval 95%, while gonadosomatic index (GSI) and gonad histology were analysed descriptively. No significant differences were observed between diploid and triploid fish in terms of growth performance, feed conversion ratio, and survival rate (P>0.05) during the two months rearing period, while GSI was higher in diploid (P<0.05) compared to triploid females. Histological observations of triploid female gonads showed early development stage, indicating sterility through symptoms such as oocytes degradation and abnormal development. Meanwhile, male gonad developed faster compared to female as spermatids were found in several lobules. As conclusion, diploid and triploid striped catfish <em>P. hypophthalmus </em>growth performance did not differ up to the age of 11 months, although some sterility symptoms were observed in both male and female.</p><p> </p><p>Keywords: diploid, triploid, growth, gonad, <em>Pangasianodon hypophthalmus </em></p><p><em> </em></p><p> </p><p><strong>ABSTRAK </strong></p><p> </p><p>Penelitian ini bertujuan untuk mengevaluasi performa pertumbuhan dan perkembangan gonad ikan patin siam <em>Pangasianodon hypophthalmus </em>diploid dan triploid. Triploid diproduksi dengan kejut suhu panas pada suhu 42 °C selama dua menit, pada dua menit setelah fertilisasi. Sebelum pengujian, kelompok diploid dan triploid dipisahkan dengan menganalisis jumlah nukleolus yang dikonfirmasi dengan penghitungan jumlah kromosom. Masing-masing lima ekor ikan diploid dan triploid pada umur sembilan bulan ditandai dan dipelihara selama dua bulan. Parameter pertumbuhan, rasio konversi pakan, dan kelangsungan hidup dianalisis menggunakan <em>independent-samples t-test </em>pada selang kepercayaan 95% sedangkan gonadosomatik indeks (GSI) dan histologi gonad dianalisis secara deskriptif. Pertumbuhan, rasio konversi pakan, dan kelangsungan hidup antara diploid dan triploid selama dua bulan pemeliharaan tidak menunjukkan perbedaan yang nyata (P>0,05). Nilai GSI diploid lebih tinggi (P<0,05) dibandingkan triploid, baik pada jantan maupun betina. Hasil histologi menunjukkan bahwa gonad ikan patin betina masih pada tahap perkembangan awal. Namun, indikasi steril terlihat dengan adanya degradasi oosit dan perkembangannya yang terganggu. Gonad jantan berkembang lebih cepat dibandingkan betina, dengan ditemukannya spermatid pada beberapa lobule. Gonad jantan triploid menunjukkan adanya gejala sterilitas tetapi tidak permanen, sebagian masih mampu berkembang hingga fase spermatid, namun jumlahnya lebih sedikit dibandingkan diploid. Berdasarkan penelitian, disimpulkan bahwa pertumbuhan antara ikan patin siam diploid dan triploid hingga umur 11 bulan tidak menunjukkan perbedaan, akan tetapi gejala sterilitas ditemukan baik pada jantan maupun betina triploid.</p><p> </p><p>Kata kunci: diploid, triploid, pertumbuhan, gonad, <em>Pangasianodon hypophthalmus</em></p>
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Piprek, Rafal P., Dagmara Podkowa, Malgorzata Kloc, and Jacek Z. Kubiak. "Expression of primary cilia-related genes in developing mouse gonads." International Journal of Developmental Biology 63, no. 11-12 (2019): 615–21. http://dx.doi.org/10.1387/ijdb.190049rp.
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Mechanisms governing differentiation of the bipotential gonad into the testes or ovaries are complex and still vague. The primary cilium is an organelle involved in cell signaling, which controls the development of many organs, but the role of primary cilium in the sex determination and sexual differentiation of gonads is com-pletely unknown. Here we studied the expression of genes involved in primary cilium formation and function-ing in fetal mouse gonads, before, during and after sexual differentiation. We studied the expression of 175 primary cilia-related genes using microarray technique. 144 of these genes were ubiquitously expressed in all studied cell types with no significant differences in expression level. Such a high level of expression of primary cilia-related genes in developing mouse gonads suggests that the primary cilia and/or primary cilia-related genes are important for the development of both somatic and germline component of the gonads. Only 31 genes showed a difference in expression between different cell types, which suggests that they have different functions in the somatic and germ cells. These results justify further studies on the role of primary cilia and the primary cilia-related genes in gonad development.
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Major, Andrew T., Katie L. Ayers, Justin Chue, Kelly N. Roeszler, and Craig A. Smith. "FOXL2 antagonises the male developmental pathway in embryonic chicken gonads." Journal of Endocrinology 243, no. 3 (December 2019): 211–28. http://dx.doi.org/10.1530/joe-19-0277.
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FOXL2 is a conserved transcription factor with a central role in ovarian development and function. Studies in humans and mice indicate that the main role of FOXL2 is in the postnatal ovary, namely folliculogenesis. To shed light on the function and evolution of FOXL2 in the female gonad, we examined its role in embryonic avian gonads, using in ovo overexpression and knockdown. FOXL2 mRNA and protein are expressed female specifically in the embryonic chicken gonad, just prior to the onset of sexual differentiation. FOXL2 is expressed in the medullary cord cells, in the same cell type as aromatase (CYP19A1). In addition, later in development, expression also becomes localised in a subset of cortical cells, distinct from those expressing oestrogen receptor alpha. Misexpression of FOXL2 in the male chicken embryonic gonad suppresses the testis developmental pathway, abolishing local expression of the male pathway genes SOX9, DMRT1 and AMH and repressing Sertoli cell development. Conversely, knockdown of FOXL2 expression allows ectopic activation of SOX9 in female gonads. However, misexpression of FOXL2 alone was insufficient to activate aromatase expression in male gonads, while FOXL2 knockdown did not affect aromatase expression in females. These results indicate that FOXL2 plays an important role in embryonic differentiation of the avian ovary via antagonism of SOX9, but may be dispensable for aromatase activation at embryonic stages. The data suggest that FOXL2 has different roles in different species, more central for embryonic ovarian differentiation in egg-laying vertebrates.
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Scarlet, D., U. Reichart, G. Podico, R. Ellerbrock, I. Canisso, I. Walter, and C. Aurich. "57 Primordial germ cell distribution in the horse fetal gonad." Reproduction, Fertility and Development 32, no. 2 (2020): 154. http://dx.doi.org/10.1071/rdv32n2ab57.
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Germ cell development and differentiation is a complex process associated with down-regulation of stem cell-associated genes and up-regulation of markers of germ cell differentiation and meiosis. In horses, putative primordial germ cells (PGCs) were identified outside the gonads starting 20 days after ovulation (Curran et al. 1997 Equine Vet. J. Suppl. 25, 72-76). However, no information is available after the time when these cells enter the gonad. The aim of this study was to identify, localise, and quantify PGCs in fetal male and female gonads. Twelve (5 males and 7 females) equine fetuses were collected transcervically 60 days after ovulation. Fetuses were entirely fixed in formaldehyde and gonads were subsequently localised. Fetal gonads underwent multiplex immunofluorescence staining for pre-meiotic germ cell marker LIN28, stem-cell associated marker CD117, and cell proliferation marker Ki67. Specificity of the primary antibodies for equine samples has been first validated. Quantification of fluorescence positive areas for LIN28, CD117, and Ki67 in the fetal gonads was done using a macro for ImageJ. Furthermore, we analysed the co-localization of above-mentioned markers using the same macro. Statistical comparison for differences between males and females was performed using non-parametric tests. In both sexes, PGCs proliferated as determined by double immunofluorescence of Ki67 and LIN28. Protein expression of LIN28 and Ki67 was highly correlated (r=0.92; P=0.003). In the fetal female gonad, PGCs were organised in cord-like structures localised in the cortical region, but there were also LIN28+ cells in the surface germinal epithelium. In the fetal male gonad, PGCs were restricted to the already developed tubular structures. Fewer LIN28+ cells (3.0±0.4% vs. 4.5±0.3%; P<0.05) were present in female than in male gonads. The distribution pattern of the stem cell factor receptor CD117 was similar to LIN28, as 86.8±3.2% of LIN28+ cells in females and 84.6±4.7% in males were also CD117+. However, immunofluorescent co-localization analysis revealed a subpopulation of CD117+ cells (43.1±8.1% in females and 46.1±6.1% in males), which did not show an overlap with LIN28. These were presumably stem cells localised in the medullar area of the gonad. In summary, we analysed for the first time spatial distribution of PGCs in fetal equine gonads. We demonstrated LIN28 to be a specific marker for PGCs also in the horse gonad, which is in agreement with the situation in human and other species. Furthermore, we identified stem cells and described their localization in the fetal equine gonad. Nevertheless, the temporal distribution of PGC and stem cells in the developing horse gonad and the role of LIN28 in the maintenance of the germline stem cell state still need to be investigated.
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Domagała, Józef, Lucyna Kirczuk, Katarzyna Dziewulska, and Małgorzata Pilecka-Rapacz. "The Annual Reproductive Cycle of Rudd, Scardinius erythrophthalmus (Cyprinidae) from the Lower Oder River and Lake Dąbie, (NW Poland)." Folia Biologica 68, no. 1 (March 31, 2020): 23–33. http://dx.doi.org/10.3409/fb_68-1.04.
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The rudd is a common freshwater species of the European ichthyofauna, however, this species' sexual cycle has not yet been described based on the histological analysis of its gonads. The aim of this study was to analyze the annual gonad development cycle of rudd from the watercourses of north-western Poland. Adult individuals aged 2+ to 13+, of both sexes were caught in the Oder River and Lake Dąbie. A standard paraffin technique and six-stage scales were used to assess the development of gonad maturity in both sexes. Rudd gonads developed similarly in the Oder River and Lake Dąbie. Eggs were deposited in batches from the beginning of May to the half of June. Females deposited at least two batches of eggs. In the majority of females collected from these sites, the gonads developed asynchronously throughout the year. Rudd males attained reproductive readiness in the same period as the females, but retained gametes in their gonads for a month longer than the females. Rudd avoid locations with warmer water discharged from power plants.
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Chen, Yadong, Yongtao Xia, Changwei Shao, Lei Han, Xuejie Chen, Mengjun Yu, and Zhenxia Sha. "Discovery and identification of candidate sex-related genes based on transcriptome sequencing of Russian sturgeon (Acipenser gueldenstaedtii) gonads." Physiological Genomics 48, no. 7 (July 1, 2016): 464–76. http://dx.doi.org/10.1152/physiolgenomics.00113.2015.
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As the Russian sturgeon ( Acipenser gueldenstaedtii) is an important food and is the main source of caviar, it is necessary to discover the genes associated with its sex differentiation. However, the complicated life and maturity cycles of the Russian sturgeon restrict the accurate identification of sex in early development. To generate a first look at specific sex-related genes, we sequenced the transcriptome of gonads in different development stages (1, 2, and 5 yr old stages) with next-generation RNA sequencing. We generated >60 million raw reads, and the filtered reads were assembled into 263,341 contigs, which produced 38,505 unigenes. Genes involved in signal transduction mechanisms were the most abundant, suggesting that development of sturgeon gonads is under control of signal transduction mechanisms. Differentially expressed gene analysis suggests that more genes for protein synthesis, cytochrome c oxidase subunits, and ribosomal proteins were expressed in female gonads than in male. Meanwhile, male gonads expressed more transposable element transposase, reverse transcriptase, and transposase-related genes than female. In total, 342, 782, and 7,845 genes were detected in intersex, male, and female transcriptomes, respectively. The female gonad expressed more genes than the male gonad, and more genes were involved in female gonadal development. Genes (sox9, foxl2) are differentially expressed in different sexes and may be important sex-related genes in Russian sturgeon. S ox9 genes are responsible for the development of male gonads and foxl2 for female gonads.
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Akbulut, Cansu, and Nazan Yön. "Histological effects of linear alkyl benzene sulfonic acid exposure on primordial germ cell migration and gonad formation in Zebrafish (Danio rerio)." Archives of Biological Sciences 71, no. 4 (2019): 589–95. http://dx.doi.org/10.2298/abs190323041a.
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The use of detergents has become widespread and is growing. The increase in population and use of detergent threatens the life of organisms in the ecosystem. In this study, the histological effects of linear alkyl benzene sulphonic acid on primordial germ cell (PGC) migration and gonad formation in zebrafish were investigated after application of 0.25 0.5 and 1 mg/L of linear alkyl benzene sulphonic acid to embryos. Samples of embryos and larvae were collected for 60 days and the effects of linear alkyl benzene sulphonic acid on PGC migration and gonad development were examined by histological procedures. The localization and migration pathway of PGCs and structures of the gonads were inspected by Periodic Acid Schiff (PAS), alkaline phosphatase, toluidine blue and Best?s carmine staining. Primordial germ cells were observed in ectopic regions and delayed gonadal development and histopathological changes in gonad structures were observed. We concluded that linear alkyl benzene sulfonic acid exposure has a negative effect on the reproduction system of zebrafish.
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Oliveira, F., A. Santos, and A. A. Neto. "70 GONADAL DEVELOPMENT IN GUINEA PIG MALES (CAVIA PORCELLUS)." Reproduction, Fertility and Development 28, no. 2 (2016): 164. http://dx.doi.org/10.1071/rdv28n2ab70.
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Sexual differentiation in mammals is an event that presents many variations between species. Because it is related to hormonal function, any imbalance in the androgens and estrogens production can lead to malformations. Because sexual differentiation occurs in different ways among various animals, the recognition of their peculiarities becomes important in order to correct reproductive handling in different species. Considering that the guinea pig is commonly used as an experimental model in the reproductive area, the goal of this work was to perform a morphological description of gonad differentiation of the male guinea pig during embryonic development. In total, 11 conceptuses with ages 25 (n = 3), 30 (n = 2), 40 (n = 2), 50 (n = 2), and 65 (n = 2) days were used for light microscopy processing. The embryos at 25 days were processed completely. For the others, the gonads were dissected. The samples were dehydrated in alcohol, embedded in paraffin, and 5-µm sections were stained with hematoxylin-eosin. In the guinea pig gonad at 25 days gestation, there was a presence of gonadal cords, formed by condensation of somatic cells, which is characteristic of an undifferentiated gonad. In addition, we observed the presence of mesonephric and paramesonephric ducts in different embryos, indicating that other genital system organs were not formed. For the 30 days of development of guinea pigs, we observed that gonadal cords were differentiated in testicular cords by invasion of mesenchymal and endothelial cells, and also composed of Sertoli cells and primordial germ cells. These cords were among a large amount of testicular mesenchyme at the 40-day group. With 50- and 65-day development samples, the gonad was completely differentiated into testicle, with the presence of spermatogonia and Sertoli cells in the seminiferous tubules, and a large amount of interstitial Leydig cells around the tubules. We conclude that gonadal differentiation in guinea pig males occurs around the middle of pregnancy, between 25 and 30 days and that, before the end of the pregnancy, at 50 days, the testicle presents morphology similar to that found in the postnatal period.
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Saravanan, Raju, Paulraj Jawahar, Thommai Francis, Baboonsundaram Ahilan, and Rajagopal Santhakumar. "Influence of Sea Surface Temperature on the Gonadal Development of Sea Urchin Temnopleurus Toreumaticus from the Gulf of Mannar, South East Coast of India." Current World Environment 11, no. 1 (April 25, 2016): 133–41. http://dx.doi.org/10.12944/cwe.11.1.17.
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This study was conducted for a 20 months period from October 2013 to May 2015 in Gulf of Mannar, south east coast of India. During the investigation the abiotic factors viz., Sea surface temperature (SST), Daylight photoperiod and atmospheric temperature data were collected from International comprehensive Ocean Atmospheric Database (ICOADS) and the reproductive cycle of the sea urchin was studied from the monthly sampling of sea urchin collected from Vedalai landing centre in Gulf of Mannar. The gonads were studied to calculate Gonad index as well histological to categories them into four different stages of the development and this data was compared with abiotic factors to study the influence of it on the reproductive behavior of sea urchin. The data were analyzed statistically through Pearson correlation and it was found negative between mean monthly gonad index and day length photoperiod, as well as with SST. This clearly indicates that the gonadal development in sea urchin is very much influenced by these two abiotic factors; however other nutritional factors might play greater role in the development gonad.
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Boizet-Bonhoure, Brigitte. "Development and pathology of the gonad." Seminars in Cell & Developmental Biology 45 (September 2015): 57–58. http://dx.doi.org/10.1016/j.semcdb.2015.11.009.
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McLaren, Anne. "Gonad development: Assembling the mammalian testis." Current Biology 8, no. 5 (February 1998): R175—R177. http://dx.doi.org/10.1016/s0960-9822(98)70104-6.
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Eggers, Stefanie, Thomas Ohnesorg, and Andrew Sinclair. "Genetic regulation of mammalian gonad development." Nature Reviews Endocrinology 10, no. 11 (September 23, 2014): 673–83. http://dx.doi.org/10.1038/nrendo.2014.163.
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Oliveira, Mônica Rocha de, and Sathyabama Chellappa. "Temporal Dynamics of Reproduction inHemiramphus brasiliensis(Osteichthyes: Hemiramphidae)." Scientific World Journal 2014 (2014): 1–8. http://dx.doi.org/10.1155/2014/837151.
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The reproductive aspects ofHemiramphus brasiliensiswere analyzed with a view to verify the temporal dynamics of reproduction. This paper presents data on sex ratio, length at first sexual maturity, macroscopic and histological aspects of gonad development, gonadosomatic index (GSI), reproductive period, and fecundity ofH. brasiliensis. The fishes were captured from the coastal waters of Rio Grande do Norte, northeastern Brazil. Females of this species predominated in the sampled population and were larger in size than the males. The length at the first sexual maturation of males was 20.8 cm and that of females was 21.5 cm. The macroscopic characteristics of the gonads indicated four maturation stages. Histological studies of gonads ofH. brasiliensisshowed six phases of oocyte development and four phases of spermatocyte development. The batch fecundity of this species was 1153 (±258.22) mature oocytes for 50 g body weight of female. The microscopic characteristics of gonad development indicate thatH. brasiliensisis a multiple spawner, presenting a prolonged reproductive period during the whole year, with a peak in the month of April, and is considered as an opportunistic strategist.
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Lecluze, Estelle, Antoine D. Rolland, Panagiotis Filis, Bertrand Evrard, Sabrina Leverrier-Penna, Millissia Ben Maamar, Isabelle Coiffec, et al. "Dynamics of the transcriptional landscape during human fetal testis and ovary development." Human Reproduction 35, no. 5 (May 1, 2020): 1099–119. http://dx.doi.org/10.1093/humrep/deaa041.
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Abstract STUDY QUESTION Which transcriptional program triggers sex differentiation in bipotential gonads and downstream cellular events governing fetal testis and ovary development in humans? SUMMARY ANSWER The characterization of a dynamically regulated protein-coding and non-coding transcriptional landscape in developing human gonads of both sexes highlights a large number of potential key regulators that show an early sexually dimorphic expression pattern. WHAT IS KNOWN ALREADY Gonadal sex differentiation is orchestrated by a sexually dimorphic gene expression program in XX and XY developing fetal gonads. A comprehensive characterization of its non-coding counterpart offers promising perspectives for deciphering the molecular events underpinning gonad development and for a complete understanding of the etiology of disorders of sex development in humans. STUDY DESIGN, SIZE, DURATION To further investigate the protein-coding and non-coding transcriptional landscape during gonad differentiation, we used RNA-sequencing (RNA-seq) and characterized the RNA content of human fetal testis (N = 24) and ovaries (N = 24) from 6 to 17 postconceptional week (PCW), a key period in sex determination and gonad development. PARTICIPANTS/MATERIALS, SETTING, METHODS First trimester fetuses (6–12 PCW) and second trimester fetuses (13–14 and 17 PCW) were obtained from legally induced normally progressing terminations of pregnancy. Total RNA was extracted from whole human fetal gonads and sequenced as paired-end 2 × 50 base reads. Resulting sequences were mapped to the human genome, allowing for the assembly and quantification of corresponding transcripts. MAIN RESULTS AND THE ROLE OF CHANCE This RNA-seq analysis of human fetal testes and ovaries at seven key developmental stages led to the reconstruction of 22 080 transcripts differentially expressed during testicular and/or ovarian development. In addition to 8935 transcripts displaying sex-independent differential expression during gonad development, the comparison of testes and ovaries enabled the discrimination of 13 145 transcripts that show a sexually dimorphic expression profile. The latter include 1479 transcripts differentially expressed as early as 6 PCW, including 39 transcription factors, 40 long non-coding RNAs and 20 novel genes. Despite the use of stringent filtration criteria (expression cut-off of at least 1 fragment per kilobase of exon model per million reads mapped, fold change of at least 2 and false discovery rate adjusted P values of less than <1%), the possibility of assembly artifacts and of false-positive differentially expressed transcripts cannot be fully ruled out. LARGE-SCALE DATA Raw data files (fastq) and a searchable table (.xlss) containing information on genomic features and expression data for all refined transcripts have been submitted to the NCBI GEO under accession number GSE116278. LIMITATIONS, REASONS FOR CAUTION The intrinsic nature of this bulk analysis, i.e. the sequencing of transcripts from whole gonads, does not allow direct identification of the cellular origin(s) of the transcripts characterized. Potential cellular dilution effects (e.g. as a result of distinct proliferation rates in XX and XY gonads) may account for a few of the expression profiles identified as being sexually dimorphic. Finally, transcriptome alterations that would result from exposure to pre-abortive drugs cannot be completely excluded. Although we demonstrated the high quality of the sorted cell populations used for experimental validations using quantitative RT-PCR, it cannot be totally excluded that some germline expression may correspond to cell contamination by, for example, macrophages. WIDER IMPLICATIONS OF THE FINDINGS For the first time, this study has led to the identification of 1000 protein-coding and non-coding candidate genes showing an early, sexually dimorphic, expression pattern that have not previously been associated with sex differentiation. Collectively, these results increase our understanding of gonad development in humans, and contribute significantly to the identification of new candidate genes involved in fetal gonad differentiation. The results also provide a unique resource that may improve our understanding of the fetal origin of testicular and ovarian dysgenesis syndromes, including cryptorchidism and testicular cancers. STUDY FUNDING/COMPETING INTEREST(S) This work was supported by the French National Institute of Health and Medical Research (Inserm), the University of Rennes 1, the French School of Public Health (EHESP), the Swiss National Science Foundation [SNF n° CRS115_171007 to B.J.], the French National Research Agency [ANR n° 16-CE14-0017-02 and n° 18-CE14-0038-02 to F.C.], the Medical Research Council [MR/L010011/1 to P.A.F.] and the European Community’s Seventh Framework Programme (FP7/2007-2013) [under grant agreement no 212885 to P.A.F.] and from the European Union’s Horizon 2020 Research and Innovation Programme [under grant agreement no 825100 to P.A.F. and S.M.G.]. There are no competing interests related to this study.
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Tolon, Mustafa Tolga, and Serhat Engin. "Gonadal development of the holothurian Holothuria polii (Delle Chiaje, 1823) in spawning period at the Aegean Sea (Mediterranean Sea)." Ege Journal of Fisheries and Aquatic Sciences 36, no. 4 (December 1, 2019): 379–85. http://dx.doi.org/10.12714/egejfas.36.4.09.
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The Mediterranean sea cucumbers including Holothuria polii has become commercially important in international trade due to the high demand of consumers from Far East countries. Sea cucumbers fisheries is a valuable income for the regional fishermen but natural stocks endangered by overfishing in recent years. Fisheries regulations and aquaculture studies are important precautions for preserving natural stocks. All these efforts are based on reproduction biology of this species which slightly differed among regions. In this study, the reproduction biology including morphological characteristics, gonadosomatic index and gonadal development stages of H.polii at the eastern coast of Aegean Sea (Izmir, Turkey) were investigated during the reproduction (spawning) period from July to October 2018. Gonads and gonad sections of 60 sea cucumbers (120.60 ± 19.56 g) have been observed by macroscopic and microscopic inspections. Three gonadal development stages have been identified by histologic observations as mature (III), spawning (IV) and post-spawning stage (V) in gonadal tubules. Results indicate that both female and male gonads are at mature and spawning stage in July and all gonads are at post-spawning stage in October. The mean gonad weight was 12.53 ± 1.33 g at the beginning of the spawning period (July) and 1.87 ± 0.58 g at the end of the spawning period (October). Gonadosomatic index decreased from 17.53 ± 0.02% (July) to 3.37 ± 0.01% (October) after spawning. The gonadosomatic index, gonad weight, and spawning were related to the seawater temperature. According to this study, the spawning period of H.polii at the eastern coasts of the Aegean Sea starts in July and completely ends in October. As a result, the data related to the reproduction biology in spawning period of H.polii would guide stock management and artificial breeding of this species under controlled conditions.
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Cool, Jonah, Tony J. DeFalco, and Blanche Capel. "Vascular-mesenchymal cross-talk through Vegf and Pdgf drives organ patterning." Proceedings of the National Academy of Sciences 108, no. 1 (December 20, 2010): 167–72. http://dx.doi.org/10.1073/pnas.1010299108.
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The initiation of de novo testis cord organization in the fetal gonad is poorly understood. Endothelial cell migration into XY gonads initiates testis morphogenesis. However, neither the signals that regulate vascularization of the gonad nor the mechanisms through which vessels affect tissue morphogenesis are known. Here, we show that Vegf signaling is required for gonad vascularization and cord morphogenesis. We establish that interstitial cells express Vegfa and respond, by proliferation, to endothelial migration. In the absence of vasculature, four-dimensional imaging of whole organs revealed that interstitial proliferation is reduced and prevents formation of wedge-like structures that partition the gonad into cord-forming domains. Antagonizing vessel maturation also reduced proliferation. However, proliferation of mesenchymal cells was rescued by the addition of PDGF-BB. These results suggest a pathway that integrates initiation of vascular development and testis cord morphogenesis, and lead to a model in which undifferentiated mesenchyme recruits blood vessels, proliferates in response, and performs a primary function in the morphogenesis and patterning of the developing organ.
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Li, Yang, Jer Ming Chia, Richard Bartfai, Alan Christoffels, Gen Hua Yue, Ke Ding, Mei Yin Ho, James A. Hill, Elia Stupka, and Laszlo Orban. "Comparative Analysis of the Testis and Ovary Transcriptomes in Zebrafish by Combining Experimental and Computational Tools." Comparative and Functional Genomics 5, no. 5 (2004): 403–18. http://dx.doi.org/10.1002/cfg.418.
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Studies on the zebrafish model have contributed to our understanding of several important developmental processes, especially those that can be easily studied in the embryo. However, our knowledge on late events such as gonad differentiation in the zebrafish is still limited. Here we provide an analysis on the gene sets expressed in the adult zebrafish testis and ovary in an attempt to identify genes with potential role in (zebra)fish gonad development and function. We produced 10 533 expressed sequence tags (ESTs) from zebrafish testis or ovary and downloaded an additional 23 642 gonad-derived sequences from the zebrafish EST database. We clustered these sequences together with over 13 000 kidney-derived zebrafish ESTs to study partial transcriptomes for these three organs. We searched for genes with gonad-specific expression by screening macroarrays containing at least 2600 unique cDNA inserts with testis-, ovary- and kidney-derived cDNA probes. Clones hybridizing to only one of the two gonad probes were selected, and subsequently screened with computational tools to identify 72 genes with potentially testis-specific and 97 genes with potentially ovary-specific expression, respectively. PCR-amplification confirmed gonad-specificity for 21 of the 45 clones tested (all without known function). Our study, which involves over 47 000 EST sequences and specialized cDNA arrays, is the first analysis of adult organ transcriptomes of zebrafish at such a scale. The study of genes expressed in adult zebrafish testis and ovary will provide useful information on regulation of gene expression in teleost gonads and might also contribute to our understanding of the development and differentiation of reproductive organs in vertebrates.
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Asaduzzaman, Md, Aysha Rahi Noor, Md Moshiur Rahman, Sumi Akter, Nayeema Ferdausy Hoque, Abrar Shakil, and Md Abdul Wahab. "Reproductive Biology and Ecology of the Green Mussel Perna viridis: A Multidisciplinary Approach." Biology 8, no. 4 (November 15, 2019): 88. http://dx.doi.org/10.3390/biology8040088.
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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. Mussels were collected throughout the year from the coastal region of the Bay of Bengal of Bangladesh, and the histological analysis of 242 mussels revealed five stages of gametogenesis with an annual spawning season from January to April. The gonadosomatic index showed a strong correlation with the water quality parameters, ingested gut plankton groups, and gonadal fatty acids, and also displayed prominent effects of seasonality. In all datasets, we performed principal component analysis in which the first two principal components showed that seasonality explained >65% of the variability, and the multivariate spaces of seasonality corresponded to the gonad development. High salinity, nutrients, chlorophyll a, and plankton abundance in the water column were positively correlated with gonad development and the spawning of mussels. During the development stage, mussel ingested more plankton, particularly Bacillariophyceae and Pyrrophyceae, which were an important source of increased n-3 polyunsaturated fatty acids content in gonads. Furthermore, gonads accumulated more lipids and saturated fatty acids during the mature and spawning stages, which were probably utilized during embryogenesis and early larval development as energy sources and constituents of the cell membrane. This research provides a model toward a better understanding of reproductive biological traits and how these traits are interrelated with the surrounding environmental variables of the green mussel, which would be helpful in marine aquaculture and the sustainable exploitation of the fishery resources.
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Piprek, Rafał P., Malgorzata Kloc, Paulina Mizia, and Jacek Z. Kubiak. "The Central Role of Cadherins in Gonad Development, Reproduction, and Fertility." International Journal of Molecular Sciences 21, no. 21 (November 4, 2020): 8264. http://dx.doi.org/10.3390/ijms21218264.
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Cadherins are a group of membrane proteins responsible for cell adhesion. They are crucial for cell sorting and recognition during the morphogenesis, but they also play many other roles such as assuring tissue integrity and resistance to stretching, mechanotransduction, cell signaling, regulation of cell proliferation, apoptosis, survival, carcinogenesis, etc. Within the cadherin superfamily, E- and N-cadherin have been especially well studied. They are involved in many aspects of sexual development and reproduction, such as germline development and gametogenesis, gonad development and functioning, and fertilization. E-cadherin is expressed in the primordial germ cells (PGCs) and also participates in PGC migration to the developing gonads where they become enclosed by the N-cadherin-expressing somatic cells. The differential expression of cadherins is also responsible for the establishment of the testis or ovary structure. In the adult testes, N-cadherin is responsible for the integrity of the seminiferous epithelium, regulation of sperm production, and the establishment of the blood–testis barrier. Sex hormones regulate the expression and turnover of N-cadherin influencing the course of spermatogenesis. In the adult ovaries, E- and N-cadherin assure the integrity of ovarian follicles and the formation of corpora lutea. Cadherins are expressed in the mature gametes and facilitate the capacitation of sperm in the female reproductive tract and gamete contact during fertilization. The germ cells and accompanying somatic cells express a series of different cadherins; however, their role in gonads and reproduction is still unknown. In this review, we show what is known and unknown about the role of cadherins in the germline and gonad development, and we suggest topics for future research.
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Prianto, Eko, Mohammad Mukhlis Kamal, Ismudi Muchsin, and Endi Setiadi Kartamihardja. "BIOLOGI REPRODUKSI IKAN BETOK (Anabas testudineus) DI PAPARAN BANJIRAN LUBUK LAMPAM,KABUPATEN OGAN KOMERING ILIR." BAWAL Widya Riset Perikanan Tangkap 6, no. 3 (December 31, 2015): 137. http://dx.doi.org/10.15578/bawal.6.3.2014.137-146.
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Ikan betok (Anabas testudineus) adalah salah satu jenis ikan ekonomis penting yang dihasilkan dari perairan paparan banjiran. Penelitian yang bertujuan untuk mengkaji beberapa aspek biologi reproduksi ikan betok di paparan banjiran Lubuk Lampam, Kabupaten Ogan Komering Ilir dilakukan pada bulan Nopember 2012-Oktober 2013. Sampel ikan ditangkap setiap bulanmenggunakan alat tangkap jaring dan bengkirai.Analisis data meliputi sebaran frekuensi ukuran panjang, nisbah kelamin, tingkat kematangan gonad, indeks kematangan gonad, ukuran pertamakali matang gonad, potensi reproduksi dan pola reproduksi. Jumlah sampel ikan betok yang diperoleh sebanyak 540 ekor, terdiri dari 187 ekor ikan jantan dan 353 ekor ikan betina, dengan kisaran panjang ikan betina antara 27-224 mm dan ikan jantan antara 48-243 mm. Rasio kelamin ikan jantan dan betina adalah 0,53 : 1. Tingkat kematangan gonad (TKG) ikan jantan dan betina yang paling banyak ditemui adalah TKG I dengan frekuensi tertinggi pada ukuran 116-132 mm dan 114-129 mmmasing-masing berjumlah 34 dan 33 ekor. Perkembangan tingkat kematangan gonad ikan betok dipengaruhi oleh perubahan tinggimuka air secara musiman. Indek kematangan gonad ikan jantan pada TKGIV berkisar 1,3-15,0%dan ikan betina berkisar antara 1,2 17,1%. Ukuran pertama kali matang gonad ikan betina adalah pada panjang total 160 mm dan ikan jantan pada panjang total 177 mm. Fekunditas ikan betok berkisar antara 224–182.736 butir dengan diameter telur berkisar antara 0,465-1,026 mmdengan pola pemijahan secara sebagian. Climbing perch, Anabas testudineus is a dominant commercial fish inhabit floodplain area of Lubuk Lampam, Ogan Komering Ilir Regency. A study aimed to investigate some aspects of the reproductive biology of climbing perch has been conducted at floodplain of Lubuk Lampam, Ogan Komering Ilir regency from November 2012 to October 2013. Fish sampling was conducted every month using nets and bamboo trap. The data analysis includes lenght frequency distribution, sex ratio, the gonado maturity, gonado somatic index, the size at first maturity, fecundity and reproductive patterns. Climbing perch sample amounted of 540 specimen compose of 187 males and 353 females, with the lenght frequency between 27-224 mm (female) and 48-243 mm (male). Sex ratio of the male and female of the climbing perch was 0,53 : 1. The gonado maturity of male and female are mostly at the first level with the highest frequency between 116-132 mm and 114-129 mm, equivalent to 34 and 33 specimen, respectively. The development of gonado maturity of climbing perch was influenced by seasonally of water level fluctuation. Gonado somatic index of maturity of male and female range 1.3-15.0% and 1.2 -17.1%, respectively. The size at the first maturity of the female was 160 mm lenght and of the male was 177 mm lenght. The fecundity ranges 224 to182,736 eggs with the egg diameter ranges 0.465-1.026 mm and the climbing perch was classified into partially spawner.
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Santos, CM, GV Lima, AA Nascimento, A. Sales, and LMY Oshiro. "Histological and histochemical analysis of the gonadal development of males and females of Armases rubripes (Rathbun 1897) (Crustacea, Brachyura, Sesarmidae)." Brazilian Journal of Biology 69, no. 1 (February 2009): 161–69. http://dx.doi.org/10.1590/s1519-69842009000100021.
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The objective of this study was to provide information on the histological characteristics of the gonads of male and female Armases rubripes crabs, and to try to establish a relationship between the microscopic and macroscopic stages previously identified. Thirty-six crabs were collected by hand between February 2003 and January 2004 in banks of Spartina alterniflora on Sahy Beach in Mangaratiba, Rio de Janeiro state, Brazil. The histological analysis of the ovaries of A. rubripes demonstrated a gradual process of development of the oocytes. According to their cellular characteristics, five types of cells were distinguished: oogonia, oocyte I, oocyte II, oocyte III and oocyte IV. The ovaries showed four stages during gonadal activity: stage I (rudimentary), stage II (developing or maturing), stage III (developed or mature) and stage IV (resting). The results of the histochemical analyses showed that the ovaries vary according to the gonad development stage. The histological aspect of one section of the male gonad was always the same in all of the seminiferous tubules, where the lumen of these tubules always contained spermatozoa and/or spermatids. It was not possible to characterize the three stages of gonad development in the males. This agrees with previous reports in the literature. However, in the females there was a relationship between the gonad stages distinguished macroscopically and the results obtained through the histological and histochemical analysis, due to the presence of different cell types, as well as the lysis process and reabsorption of the oocytes in spent females.
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Kostaman, Tatan, and Soni Sopiyana. "Primordial germ cells profiles incubated for 24 hours in phosphate buffer saline [-] solution." Jurnal Ilmu Ternak dan Veteriner 22, no. 3 (March 2, 2018): 144. http://dx.doi.org/10.14334/jitv.v22i3.1802.
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Gonadal development is a sequential process that can be divided into three major events: the PGCs migration, sex determination and gonadal differentiation. This study was aimed to see the development of PGCs isolated from the gonads of embryos after being incubated for 7 days and then was incubated using a solution of Phosphate Buffer Saline (PBS) [-]. The developing gonad can be isolated from 7 days old chick and can be incubated at a temperature of 37.8<sup>o</sup>C in a solution of PBS [-]: without Ca2+ and Mg2+. The release of gonadal PGC was observed within 1, 8, 16, and 24 hours after the embryonic gonad was placed in a PBS solution [-]. The results showed that PGCs can be separated from gonadal tissues and can be collected by entering the developing gonad to the PBS [-] solution. The highest percentage of PGCs and survival rate was obtained after gonad was incubated for 1 hour and was not different with 8 hours (P>0.05). Those result was significantly different (P<0.05) with the 16 and 24 hours incubation. The highest purity rate percentage was in the 8 hours incubation, but did not show a significant difference (P>0.05) with the 1 and 16 hours incubation. The percentage of the purity differed (P<0.05) after the 24 hours incubation. It can be concluded that the most appropriate incubation time to obtain PGCs from the KUB chicken embryonic gonad is no more than 8 hours.
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Pili Nisperos, Dulce Marie, and Gliceria B. Ramos. "ELUCIDATING THE GONADAL DEVELOPMENT AND SEX DIFFERENTIATION OF THE RICE PADDY EEL, Monopterus albus (Zuiew, 1993), BASED ON GONADAL HISTOMORPHOLOGY AND STEROID HORMONE LEVELS." Malaysian Journal of Science 40, no. 3 (October 31, 2021): 18–27. http://dx.doi.org/10.22452/mjs.vol40no3.2.
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The establishment and survival of the population of species in their breeding ground can be attributed to the species’ reproductive characteristic and capacity. The Monopterus albus species is an introduced fish in the Philippines. It is a protogynous hermaphrodite which has a natural ability for sex reversal. This study describes the histomorphology of the different stages of gonadal maturation and determines the concentration levels of the steroid hormones 17ß-estradiol (E2) and testosterone (T) in the blood plasma. These aim to a further understanding on the gonadal development and sex differentiation of the rice paddy eel as a hermaphroditic fish. Fish samples were collected randomly from farm ponds located in three provinces within the island of Luzon, Philippines. The sexual identity of the fish was categorized based on the presence or absence of ovarian and testicular tissues. Histological analysis of the gonad showed that immature, maturing-matured female gonad exhibited ovarian tissues of varying stages. The intersex gonad showed the existence of both ovarian and testicular tissues. Enzyme-linked immunosorbent assay (ELISA) was used to determine the concentration levels of gonadal steroid hormones. Differences in the concentration levels of the two hormones were evident across all the stages of gonad maturation. The functional role of these hormones in vitellogenesis and spermatogenesis leads to the development of this sex-changing gonads. This reproductive characteristic contributes to our understanding of the reproductive success of hermaphroditic fish.
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Chen, Min, Min Chen, Suren Chen, Jingjing Zhou, Fangfang Dong, Zhiming Shen, Haowei Wu, Xiuhong Cui, and Fei Gao. "Abnormal Meiosis Initiation in Germ Cell Caused by Aberrant Differentiation of Gonad Somatic Cell." Oxidative Medicine and Cellular Longevity 2019 (September 5, 2019): 1–8. http://dx.doi.org/10.1155/2019/8030697.
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The interaction between germ cell and somatic cell plays important roles in germ cell development. However, the exact function of gonad somatic cell in germ cell differentiation is unclear. In the present study, the function of gonad somatic cell in germ cell meiosis was examined by using mouse models with aberrant somatic cell differentiation. In Wt1R394W/R394W mice, the genital ridge is absent due to the apoptosis of coelomic epithelial cells. Interestingly, in both male and female Wt1R394W/R394W germ cells, STRA8 was detected at E12.5 and the scattered SYCP3 foci were observed at E13.5 which was consistent with control females. In Wt1-/flox; Cre-ERTM mice, Wt1 was inactivated by the injection of tamoxifen at E9.5 and the differentiation of Sertoli and granulosa cells was completely blocked. We found that most germ cells were located outside of genital ridge after Wt1 inactivation. STRA8, SYCP3, and γH2AX proteins were detected in germ cells of both male and female Wt1-/flox; Cre-ERTM gonads, whereas no thread-like SYCP3 signal was observed. Our study demonstrates that aberrant development of gonad somatic cells leads to ectopic expression of meiosis-associated genes in germ cells, but meiosis was arrested before prophase I. These results suggest that the proper differentiation of gonad somatic cells is essential for germ cell meiosis.
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Waiho, K., H. Fazhan, S. Jasmani, and M. Ikhwanuddin. "Gonadal development in males of the orange mud crab, Scylla olivacea (Herbst, 1796) (Decapoda, Brachyura, Portunidae)." Crustaceana 90, no. 1 (2017): 1–19. http://dx.doi.org/10.1163/15685403-00003622.
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This study describes the morphological and histological characteristics of the male reproductive system of the orange mud crab, Scylla olivacea (Herbst, 1796). Three maturation stages were determined on the basis of the vas deferens diameter, the gonad colour and the gonadosomatic index (GSI). Significant differences were observed in the GSI value as the crabs matured. All germ cells were present in the histological sections of the testes, and these decrease significantly in size as they progress from spermatogonia, spermatocytes, and spermatids to spermatozoa. Spermatophores are found in the anterior vas deferens (AVD) and median vas deferens (MVD) of all maturation stages but not in the posterior vas deferens (PVD), with a significantly smaller size in immature and maturing specimens. Thus, the classification of S. olivacea gonads into various maturation stages based solely on histological characteristics (i.e., the presence of spermatophores) is impossible. Therefore, the combination of both microscopic and macroscopic features is essential for determining the gonad maturation stages of male S. olivacea.