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Ovarian Maturation (ovarian + maturation)
Selected AbstractsDynamic changes in gene expression during vitellogenic stages of the white shrimp: Fenneropenaeus merguiensis de ManAQUACULTURE RESEARCH, Issue 6 2009Monwadee Wonglapsuwan Abstract Ovarian maturation is a crucial step for shrimp brood stock. A suppressive subtractive hybridization was used to identify differentially expressed genes in the ovaries during vitellogenesis of Fenneropenaeus merguiensis. Three- to sevenfold up-regulated genes were selected. A blast search identified nine unique genes. The genes that may be involved in ovarian maturation, namely translationally controlled tumour protein (TCTP), heat shock protein 70 (HSP70), H-L(3)MBT-LIKE, shrimp ovarian peritrophin (SOP), vitellin (Vn), thrombospondin (TSP) and ribosomal protein L10a (RPL10a), were further studied. The transcripts of HSP70, TCTP, SOP and RPL10a in the ovary showed their highest expression in the early stage and declined in the later stages. In contrast, the transcripts of the H-L(3)MBT-LIKE, TSP and Vn genes increased from the early stage to be significantly up-regulated during the late stage. A comparison of gene expression among organs during the vitellogenesis showed that the transcripts of HSP70, SOP, H-L(3)MBT-LIKE and TSP were down-regulated in the brain, intestine, hepatopancreas and lymphoid (except for TSP) when compared with their expression in shrimp with non-developed ovaries. The mRNA of TCTP and RPL10a was significantly over-expressed in the lymphoid and heart, whereas TCTP transcripts were significantly down-regulated in the brain during the vitellogenesis. The molecular behaviour of the transcripts in this study may, in the future, lead to an ability to stimulate the ovarian development in shrimp. [source] Ovarian maturation stages of the mud crab Scylla serrataAQUACULTURE RESEARCH, Issue 14 2007Emilia T Quinitio Abstract Ovarian maturation in adult wild-sourced and pond-grown Scylla serrata (Forsskål) was determined based on gross morphology and histological appearance. There were no significant differences noted in the histological features of both wild and pond-reared S. serrata females. Ovarian maturation was classified into five stages: immature, early maturing, late maturing, fully mature and spent. The immature ovaries are thin and translucent to off white and contain oogonia, primary oocytes with large nuclei. The follicle cells were found around the periphery of the lobes and an area among groups of oogonia and oocytes. The follicle cells gradually enclosed the oocytes. The early-maturing ovaries were yellow and small yolk globules started to appear in larger oocytes. In late-maturing ovaries, the colour became light orange and lobules were apparent. Yolk globules occurred in the cytoplasm with larger globular inclusions towards the periphery, while follicle cells were hardly recognizable. Fully mature ovaries were orange to deep orange and had swollen lobules. Large yolk globules were apparent in the entire cytoplasm. Follicle cells were hardly seen. Spent ovaries were similar to the early-maturing and late-maturing stage in partially spawned females. The ovarian development was correlated closely to the gonadosomatic index, oocyte diameter, and ovarian histology. The classification of ovarian maturation provides baseline information for further studies on reproductive biology. Likewise, the information provides a guide for broodstock management in the hatchery. [source] Ovarian maturation of wild Farfantepenaeus paulensis in relation to histological and visual changesAQUACULTURE RESEARCH, Issue 14 2003S Peixoto Abstract The present study describes the ovarian development stages of wild Farfantepenaeus paulensis (Pérez-Farfante) through the combined observation of histological and visual characteristics. Twenty-five females (61.8±2.4 g) were captured in 35,40-m deep waters off southern Brazil (27°S). The females were grouped according to the size and shape of their ovary and then killed. The colour of the fresh ovary was compared with a chromatic scale catalogue. Analysis of the histological sections of each ovary determined the morphological characteristics, size and frequency of the different oocyte types. Based on these characteristics, four distinct stages of ovarian maturation are proposed: stage I (immature), characterized by the presence of small basophilic oocytes (52.1±19.9 ,m) and ovary colour ranging from translucent to creamy; stage II (developing), with yolky oocytes (YOs) (144.2±26.1 ,m) and a light green colour; stage III (mature), presenting large YOs but with cortical rods (235.0±30.2 ,m) and an olive-brown colour; and stage IV (spent), with atretic oocytes and the same ovary colour pattern as stage I. The gonadosomatic index ranged from 1.6 (stage IV) to 13.7% (stage III) and was closely related to the different ovarian maturation stages. The observation of visual features coupled with histological characteristics was found to represent a reliable procedure to evaluate the ovarian maturation of F. paulensis. [source] Expressional changes of ganglioside GM3 during ovarian maturation and early embryonic development in db/db miceDEVELOPMENT GROWTH & DIFFERENTIATION, Issue 1 2003Dong Hoon Kwak Diabetes and obesity cause abnormal development of reproductive processes in a variety of species, but the mechanisms that underlie this effect have not been fully elucidated. This study examined the expressional changes of ganglioside GM3 during ovarian maturation, in vitro fertilization (IVF) and early embryonic development in diabetic/obese db/db mice. In high-performance thin-layer chromatography studies, GM3 expression was conspicuously low in the ovaries of db/db mice compared to non-diabetic db/+ mice. Signal detected by anti-GM3 monoclonal antibody was greatly reduced in the primary, secondary and graffian follicles of db/db mice compared to control mice. Results from IVF with ova and sperm from db/db mice showed that GM3 expression during early embryonic development was obviously decreased compared to db/+ mice. This study also elucidated the effects of high glucose (20 and 30 mm) on early embryonic development in ICR strain mice. High glucose caused a decrease in GM3 expression during early embryonic development. Taken together, the results of this study indicate decreased GM3 expression during ovarian maturation and embryonic development of db/db mice, suggesting that alteration of ganglioside expression induced by the diabetic condition may be implicated in the abnormal follicular embryonic development. [source] Life-history strategy in an oligophagous tephritid: the tomato fruit fly, Neoceratitis cyanescensECOLOGICAL ENTOMOLOGY, Issue 4 2008THIERRY BRÉVAULT Abstract 1.,In phytophagous insects, life-history traits mainly depend on host plant range. Substantial longevity, high fecundity and larval competition are the major traits of polyphagous Tephritidae while species with a restricted host range generally exhibit a lower longevity and fecundity as well as mechanisms to avoid larval competition. Our aim in this study was to investigate the life history of an oligophagous species, the tomato fruit fly, Neoceratitis cyanescens (Bezzi). 2.,We determined life tables under laboratory conditions in order to calculate the main demographic parameters of N. cyanescens and studied the influence of larval and adult diet on life-history traits. 3.,The mean longevity of N. cyanescens females was 40 days. There was a strong synchronisation of female maturity. Oviposition showed an early peak at 9,13 days after a short pre-oviposition period (6 days). The absence of proteins in the adult diet both delayed ovarian maturation and decreased female fecundity. In addition, females originating from tomato fruits produced significantly more eggs than females originating from bugweed or black nightshade, showing that even the larval host plant may strongly affect the subsequent fecundity of adult females. 4.,The traits of N. cyanescens are then discussed in the light of those documented for polyphagous and monophagous tephritids. Neoceratitis cyanescens displayed attributes intermediate between those of polyphagous and monophagous tephritids. Its smaller clutch size compared with polyphagous species and its specialisation on the Solanaceae family whose fruits contain toxic compounds may help in reducing intra- and inter-specific competition, respectively. [source] The sublethal effects of tebufenozide on the precopulatory and copulatory activities of Choristoneura fumiferana and C. rosaceanaENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 3 2004Renée Dallaire Abstract The sublethal effects of tebufenozide, an ecdysone agonist, on the reproductive biology of Choristoneura fumiferana (Clem) and of Choristoneura rosaceana (Harris) (Lepidoptera: Tortricidae), treated during the larval stage, were evaluated using two treatment methods: the force-feeding method and the diet method. The percentage of mortality and the developmental time of survivors increased linearly with the concentration of tebufenozide used. This ecdysone analogue proved to be more toxic to C. fumiferana than to C. rosaceana. In C. rosaceana, the weight of males and females decreased proportionally with the dose ingested, but females were affected to a greater extent. This difference might be due to a greater consumption of the treated diet, or to a differential vulnerability to tebufenozide. Tebufenozide did not modify the pre-copulatory activities associated with chemical communication in the females. However, the consumption of tebufenozide delayed ovarian maturation, causing a reduction in the fecundity of females. Treated males had smaller spermatophores and fewer eupyrene sperms in their bursa copulatrix and spermatheca, along with lower mating success. In C. fumiferana, tebufenozide delayed the females' onset time of calling the first night after emergence, but did not affect the mean time spent calling or the production of the main component of the sex pheromone. The males showed significantly greater difficulty in executing oriented flight in a wind tunnel, although their mating success was not affected. We concluded that tebufenozide interferes with various aspects of the reproductive biology of males and females of C. fumiferana and C. rosaceana, including some pre-copulatory behaviors associated with sex pheromone communication. [source] Reproductive status in females of the Brazilian catfish, Pseudoplatystoma fasciatum reared in cagesJOURNAL OF APPLIED ICHTHYOLOGY, Issue 5 2010E. Romagosa Summary The distinctive morphological features of the ovaries the ,cachara', Pseudoplatystoma fasciatum were characterized macroscopically, and by histology, when reared in cages, from March 2005 to February 2006. Forty eight females (mean total weight = 2.7 kg, mean standard length = 65.1 cm) were allocated to four cages of 2.7 m3 (20 fish/cage) which were installed in four 600 m2 ponds, located at the IP, Pariquera-Açu, São Paulo, Brazil. The monthly, samples were fixed in 4%-buffered formalin before preparation for histological examination, ovaries were removed and weighted. The gonadosomatic index (GSI) was calculated as = 100 × weight ovaries/total fish weight. The ovaries are the cystovarian type and macroscopically, were established three stages of ovarian maturation: Resting, developing Maturation (initial, intermediate, final) and Regression (initial, intermediate, final). Based on morphological criteria of those ovaries, the oocyte development has been divided into distinct stages: (i) oocyte growth (vitellogenesis); (ii) oocyte maturation, along which it goes through different phases of development, before (iii) ovulation and, (iv) spawning. When the P. fasciatum were kept in confinement and not induced to breed occurs fail to attain final oocyte maturation, start the process of degeneration. Consequently, the weight started to decline and 45% of the ovaries showed atresia of vitellogenic follicles. This was considered indicative of a recent cessation of the reproductive activity. Such failure could have been caused by stress of the monthly sampling involving a certain degree of disturbance, and perhaps also by the existence of stressors while in captivity. The synchronous ovary contained oocytes in an unique stage of development and had potential to perform total spawning up to one time a year, with the period reproductive beginning in the end of November to the beginning of February, coinciding with the highest water temperatures in the experimental cages (29.0,31.5°C) and the increase of mean values of GSI. During the regression phase, residual oocytes could be observed together with decrease of the mean values of GSI and, the temperatures. [source] Dynamic changes in gene expression during vitellogenic stages of the white shrimp: Fenneropenaeus merguiensis de ManAQUACULTURE RESEARCH, Issue 6 2009Monwadee Wonglapsuwan Abstract Ovarian maturation is a crucial step for shrimp brood stock. A suppressive subtractive hybridization was used to identify differentially expressed genes in the ovaries during vitellogenesis of Fenneropenaeus merguiensis. Three- to sevenfold up-regulated genes were selected. A blast search identified nine unique genes. The genes that may be involved in ovarian maturation, namely translationally controlled tumour protein (TCTP), heat shock protein 70 (HSP70), H-L(3)MBT-LIKE, shrimp ovarian peritrophin (SOP), vitellin (Vn), thrombospondin (TSP) and ribosomal protein L10a (RPL10a), were further studied. The transcripts of HSP70, TCTP, SOP and RPL10a in the ovary showed their highest expression in the early stage and declined in the later stages. In contrast, the transcripts of the H-L(3)MBT-LIKE, TSP and Vn genes increased from the early stage to be significantly up-regulated during the late stage. A comparison of gene expression among organs during the vitellogenesis showed that the transcripts of HSP70, SOP, H-L(3)MBT-LIKE and TSP were down-regulated in the brain, intestine, hepatopancreas and lymphoid (except for TSP) when compared with their expression in shrimp with non-developed ovaries. The mRNA of TCTP and RPL10a was significantly over-expressed in the lymphoid and heart, whereas TCTP transcripts were significantly down-regulated in the brain during the vitellogenesis. The molecular behaviour of the transcripts in this study may, in the future, lead to an ability to stimulate the ovarian development in shrimp. [source] Ovarian maturation stages of the mud crab Scylla serrataAQUACULTURE RESEARCH, Issue 14 2007Emilia T Quinitio Abstract Ovarian maturation in adult wild-sourced and pond-grown Scylla serrata (Forsskål) was determined based on gross morphology and histological appearance. There were no significant differences noted in the histological features of both wild and pond-reared S. serrata females. Ovarian maturation was classified into five stages: immature, early maturing, late maturing, fully mature and spent. The immature ovaries are thin and translucent to off white and contain oogonia, primary oocytes with large nuclei. The follicle cells were found around the periphery of the lobes and an area among groups of oogonia and oocytes. The follicle cells gradually enclosed the oocytes. The early-maturing ovaries were yellow and small yolk globules started to appear in larger oocytes. In late-maturing ovaries, the colour became light orange and lobules were apparent. Yolk globules occurred in the cytoplasm with larger globular inclusions towards the periphery, while follicle cells were hardly recognizable. Fully mature ovaries were orange to deep orange and had swollen lobules. Large yolk globules were apparent in the entire cytoplasm. Follicle cells were hardly seen. Spent ovaries were similar to the early-maturing and late-maturing stage in partially spawned females. The ovarian development was correlated closely to the gonadosomatic index, oocyte diameter, and ovarian histology. The classification of ovarian maturation provides baseline information for further studies on reproductive biology. Likewise, the information provides a guide for broodstock management in the hatchery. [source] Ovarian maturation of wild Farfantepenaeus paulensis in relation to histological and visual changesAQUACULTURE RESEARCH, Issue 14 2003S Peixoto Abstract The present study describes the ovarian development stages of wild Farfantepenaeus paulensis (Pérez-Farfante) through the combined observation of histological and visual characteristics. Twenty-five females (61.8±2.4 g) were captured in 35,40-m deep waters off southern Brazil (27°S). The females were grouped according to the size and shape of their ovary and then killed. The colour of the fresh ovary was compared with a chromatic scale catalogue. Analysis of the histological sections of each ovary determined the morphological characteristics, size and frequency of the different oocyte types. Based on these characteristics, four distinct stages of ovarian maturation are proposed: stage I (immature), characterized by the presence of small basophilic oocytes (52.1±19.9 ,m) and ovary colour ranging from translucent to creamy; stage II (developing), with yolky oocytes (YOs) (144.2±26.1 ,m) and a light green colour; stage III (mature), presenting large YOs but with cortical rods (235.0±30.2 ,m) and an olive-brown colour; and stage IV (spent), with atretic oocytes and the same ovary colour pattern as stage I. The gonadosomatic index ranged from 1.6 (stage IV) to 13.7% (stage III) and was closely related to the different ovarian maturation stages. The observation of visual features coupled with histological characteristics was found to represent a reliable procedure to evaluate the ovarian maturation of F. paulensis. [source] | |||||||||||||