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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Characterization of the 95 kDa sperm adhesion protein / Charakterizierung des 95 kDa Spermienadhäsionsproteins

Bull, Leonard 22 January 2004 (has links)
No description available.
32

The interaction between human spermatozoa and its homologous zona pellucida : scientific advances and clinical significance

Oehninger, Sergio C. 12 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2002. / ENGLISH ABSTRACT: Infertility is a very common problem worldwide. Recent data have shown that disorders of the male represent the most common single defined cause of infertility. This proposal examines the clinical significance and fundamental physiological aspects of human gamete interaction. These studies are focused on the assessment of the cellular-molecular mechanisms involved in human sperm binding to its homologous zona pellucida resulting in the physiologic induction of the acrosome reaction. We have developed and validated in vitro bioassays that assess specific steps of the fertilization process that are critical for early embryo development. The results of our translational research have already had a significant impact on the overall evaluation of male infertility and on the clinical management of the infertile man in the assisted reproduction arena. Furthermore, the unveiling of the basic mechanisms involved in human gamete interaction will ultimately allow for both (i) the development of new male reproductive diagnostic capabilities and (ii) the design of improved and safer therapies aiding conception in childless couples suffering from male infertility. / AFRIKAANSE OPSOMMING: Menslike onvrugbaarheid is 'n algemene wêreldwye probleem en onlangse data toon aan dat die manlike factor die grootste enkel bydraende factor tot hierdie toestand is. Die werk loods 'n intensiewe ondersoek na die kliniese betekenis en basiese fisiologiese aspekte wat 'n rol tydens spermsel en eisel interaksie speel. Hoofstuk 3 fokus op die sellulêre en molekulêre meganismes wat betrokke is tydens spermsel en eisel binding wat gevolglik lei tot akrosoomreaksie van die spermsel. Die werk verteenwoordig die resultate van 10 jaar se navorsing tussen die kandidaat en die promoter. Dit gee oorsprong aan 'n reeks bio-toetse wat die bevrugtingsproses koriografiese ontleed en verskaf dus 'n stap-vir-stap uiteenseting van menslike bevrugting en gevolglike embrio ontwikkeling. Die resultate in Hoostuk 4 bring vernuwing in die begrippe van die manlike faktor en die rol in die kinderlose huwelik. Die resulate soos in Hoofstuk 3 en 4 uiteengesit, vorm nie net die basis vir die moontlike ontwikkeling van nuwe diagnostiese benaderings tot die hantering van die man nies maar speel oojk 'n rol die daarstelling van verbeterde terapeutiese hantering van die kinderlose egpaar. Hoofstuk 5 gee kortliks riglyne en aanbevelings tot opsigte van die gebruik van die spermsel-zona pellucida bindingstoets en akrosomreaksie. Die kandidaat bevel aan dat die genoemde twee bio-toetse deel van die laboratorium ondersoeke van die man gebruik moet word.
33

Función del sistema plasminógeno-plasmina en la fecundación de ovocitos bovinos y porcinos

Grullón Yunén, Luis Alberto 13 December 2010 (has links)
El objetivo de este trabajo consistió en describir el papel del sistema plasminógeno/plasmina (PLG/PLA) en la fecundación bovina y porcina. Mediante fecundación in vitro, demostramos que la presencia de PLG ó PLA en el medio de coincubación de los gametos disminuía la penetración de los espermatozoides en los ovocitos y su unión a la zona pelúcida (ZP). Esta disminución no se debía a alteraciones de la funcionalidad espermática ni a cambios en la resistencia de la ZP a la proteolisis, sino a que la PLA provocaba la liberación de los espermatozoides adheridos a la ZP. Mediante inmunofluorescencia indirecta detectamos la presencia de PLG y sus activadores en la ZP y en el oolema de los ovocitos antes de la fecundación. Tras la fecundación, dicha presencia disminuyó o desapareció por completo, por lo que proponemos que el sistema PLG/PLA se activa durante la interacción espermatozoide-ovocito y contribuye a regular la polispermia. / The aim of this study was to describe the role of the plasminogen/plasmin system (PLG/PLA) in bovine and porcine fertilization. Through in vitro fertilization, we demonstrated that the presence of PLG or PLA in the incubation medium of gametes decreased penetration of oocytes and sperm binding to the zona pellucida (ZP). This decrease was not due to alterations in sperm function or changes in the ZP resistance to proteolysis, but the PLA caused the release of sperm previously bound to the ZP. By indirect immunofluorescence we detected the presence of PLG and its activators in the ZP and oolema of the oocytes before fertilization. After fertilization, this presence diminished or disappeared completely, so we propose that the PLG/PLA system is activated during sperm-oocyte interaction and contributes to the regulation of polyspermy.
34

A Morphological Study of the Canine Zona Pellucida: A Heterogeneous Ultrastructure and Barrier

Lunn, Matthew O'Brien 22 August 2011 (has links)
No description available.
35

Studie tekutin a sekretů z reprodukčních traktů prasete (Sus scrofa f. domestica) a skotu (Bos primigenius f. taurus) / The study of fluids and secretions from reproductive tracts of pig (Sus scrofa f. domestica) and cattle (Bos primigenius f. taurus)

Dráb, Tomáš January 2014 (has links)
Interactions between proteins and saccharide moieties play an indispensable role in mammalian reproduction as they stand behind of such processes as maturation and mutual recognition of gametes and sperm oviductal reservoir formation. In my dissertation thesis I focused on activities of glycosidases from bovine and porcine follicular fluids and their changes connected with follicle development. Activities of five glycosidases were detected in tertiary and preovulatory follicles in both species. The most active enzymes were α-L-fucosidase in cow and α-D-mannosidase in sow and both enzymes also demonstrated the most pronounced increase in their activities during follicle maturation. Interestingly, both α-L-fucose in cow and α-D-mannose in sow were described as saccharides responsible for the formation of the sperm oviductal reservoir and we offered a hypothetical mechanism of synchronisation between sperm release from their reservoir with the time of ovulation based on a surge of activities of corresponding follicular glycosidases through the oviduct. Subsequently, it was demonstrated that β-D-galactosidase and α-D-mannosidase affect sperm-zona pellucida binding in pig, as they both decrease interaction between sperm receptors for zona pellucida and zona pellucida. This may explain the observation...
36

A vitrificação de oócitos bovinos prejudica sua capacidade reprodutiva, independente do estadio de maturação / Vitrification of bovine oocytes impairs their reproductive capacity independently of maturation stage

Bulgarelli, Daiane Lopes 14 December 2011 (has links)
Até o momento a literatura não determinou qual o melhor estadio de maturação (imaturo ou maduro) para que o oocito mantenha sua competência para o desenvolvimento reprodutivo após a criopreservação. O objetivo deste estudo foi determinar em qual estadio meiótico (imaturo -VG (vesícula germinativa) ou maduro- MII (metáfase II)) o oócito é menos susceptível ao dano na criopreservação, utilizando modelo experimental bovino. Foram utilizados ovários de vacas abatidas em matadouro, após a aspiração dos folículos, os oócitos imaturos (VG) foram selecionados para a maturação in vitro e vitrificação, e foram divididos em três grupos: 1) oócitos maturados in vitro e não submetidos à vitrificação (CONTROLE); 2) oócitos vitrificados imaturos (VG), descongelados e submetidos à maturação in vitro (CRIO-MIV); 3) oócitos maturados in vitro (MII), vitrificados e descongelados (MIV-CRIO). Os oócitos foram avaliados quanto a: a)maturação nuclear pela técnica de orceína acética; b) integridade da zona pelúcida (ZP) através de microscopia de polarização; c) viabilidade oocitária pela técnica de DEAD-LIVE; d) desenvolvimento embrionário (taxa de clivagem, produção e eclosão de blastocistos) através da fertilização in vitro (FIV) e ativação partenogenética (AT). Não houve diferença na capacidade de maturação nuclear entre os oócitos frescos e descongelados no grupo CRIO-MIV (p=0,23). Em relação à zona pelúcida a totalidade dos oócitos (100%) nos três grupos apresentou leitura de zona pelúcida positiva, não havendo correlação com evolução embrionária posterior. Na análise de viabilidade celular pelo DEAD-LIVE verificou-se que houve redução da viabilidade do grupo MIV-CRIO (27%) quando comparado com controle (84%) (p<0,0001). Na análise do potencial de desenvolvimento embrionário o grupo controle apresentou melhores taxas de clivagem após FIV (80%) e AT (58%), do que os grupos CRIO-MIV (28%; p<0,0001; 28%; p=0,0002, respectivamente) e MIV-CRIO (26%; p<0,0001; 22%, p<0,0001,respectivamente). As taxas de formação de blastocisto e eclosão após FIV nos grupos CRIO-MIV, MIV-CRIO e após AT no grupo MIV-CRIO foram nulas. Houve a produção e eclosão de apenas um blastocisto no grupo CRIO-MIV após AT. No modelo experimental utilizado, o procedimento de vitrificação comprometeu parcialmente a viabilidade dos oócitos medida pela técnica de DEAD- LIVE e completamente o desenvolvimento embrionário subseqüente, independente do estadio de maturação meiótica (VG ou MII) durante a criopreservação. No entanto, oócitos vitrificados em estadio de VG e submetidos à MIV foram meioticamente competentes e progrediram até o estadio de MII, sugerindo que o dano não compromete a capacidade de maturação nuclear do oócito. Este estudo não conseguiu determinar qual o melhor estadio meiótico oocitário para criopreservação, já que os dois estadios meióticos (VG e MII) se mostraram igualmente prejudicados pela criopreservação em relação à capacidade reprodutiva. / Until the present literature has not achieved a consensus regarding the best maturation stage for oocyte to maintain their reproductive capacity after cryopreservation. The aim of this study was to determine, using an experimental bovine model, in which stage of development (VG stage, immature, or MII stage, post-maturation in vitro) the oocyte is less susceptible to damage during cryopreservation. Immature oocytes (VG) from the ovaries of slaughtered cows were selected for in vitro maturation or vitrification and divided into three groups. The first group (CONTROL) consisted of immature oocytes, matured in vitro without vitrification; the second group (CRYO-IVM) consisted of vitrified immature oocytes thawed and submitted to in vitro maturation; and the third group (IVM-CRYO) consisted of matured in vitro oocytes submitted to vitrification and thawing. The oocytes were evaluated for: nuclear maturation by acetic orcein staining; integrity of the zona pellucida using a polarized microscope; cell viability by the Dead-Live technique; and embryo development (cleavage, production and hatching rate) by in vitro fertilization and parthenogenetic activation. There was no difference in capacity of nuclear maturation between fresh and thawed oocytes (p=0.23). Regarding the zona pellucida (ZP), all oocytes (100%) of all three groups (control, CRYO-IVM and IVMCRYO) presented a positive ZP reading, with no correlation with later embryo evolution. DEAD-LIVE analysis of cell viability revealed reduction of viability in the IVM-CRYO group (27%) compared to control (84%) (p<0.0001) and to the CRYO-IVM group (56%) (p=0.017), with no difference between the last two groups (p=0.055). Analysis of the potential for embryo development by means of in vitro fertilization showed that the control group presented better cleavage and blastocyst formation rates than the CRYO-IVM (p<0.0001 and p<0.0001, respectively) and the IVM-CRYO (p<0.0001 and p=0.0004, respectively) groups. Analyzing the potential for embryo development the control group presented better cleavage by means of in vitro fertilization (80%) and parthenogenetic activation (58%) than the CRYOIVM (28%; p<0,0001; 28%; p=0,0002, respectively) and the IVM-CRYO groups (26%; p<0,0001; 22%, p<0,0001,respectively) Analysis of blastocyst formation rates and hatching after FIV and AT in CRYO-IVM and IVM-CRYO groups were null. Vitrification of bovine oocytes causes great impairment of their reproductive capacity regardless of the stage of maturation at the time of freezing. However the vitrified immature oocytes submitted to IVM maintained their capacity of nuclear maturation, as they achieved MII stage. This study was not able to determine which stage was better in reducing crio damage, as both stages (VG and MII) presented equally impaired by the process.
37

Avaliação da atividade antinociceptiva e anti-inflamatória da Pellucidina A e elucidação do mecanismo de ação em modelos in vivo

QUEIROZ, Amanda Pâmela dos Santos 13 October 2016 (has links)
Submitted by Nathalya Silva (nathyjf033@gmail.com) on 2017-05-30T15:35:08Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_AvaliacaoAtividadeAntinociceptiva.pdf: 1956189 bytes, checksum: 7517747ee93d0e00de15afa1deb6685f (MD5) / Approved for entry into archive by Edisangela Bastos (edisangela@ufpa.br) on 2017-06-06T21:41:17Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_AvaliacaoAtividadeAntinociceptiva.pdf: 1956189 bytes, checksum: 7517747ee93d0e00de15afa1deb6685f (MD5) / Made available in DSpace on 2017-06-06T21:41:17Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_AvaliacaoAtividadeAntinociceptiva.pdf: 1956189 bytes, checksum: 7517747ee93d0e00de15afa1deb6685f (MD5) Previous issue date: 2016-10-13 / A Peperomia pellucida (Piperaceae) é uma planta herbácea comumente encontrada nos continentes americano e asiático. Na Amazônia a espécie é conhecida pelo nome de erva-de-jabuti. Esta planta é utilizada, na medicina popular, para tratar uma vasta gama de sintomas e doenças, tais como conjuntivite, dor de cabeça, asma, úlcera gástrica, inflamação. Este estudo visou analisar a atividade antinociceptiva e anti-inflamatória dessa substância, assim como elucidar seu mecanismo de ação. Para todos os ensaios foram utilizados camundongos albinos suíços, machos (25 - 40 g), que foram inicialmente tratados com a pellucidina A nas doses de 0,5; 1 e 5 mg/kg (i.p.), submetidos a avaliação locomotora pelo ensaio de campo aberto e a modelos animais de dor aguda, como os testes de contorção abdominal induzida por ácido acético, testes da formalina e o ensaio da placa-quente. Em seguida, foi realizado o teste de contorção abdominal induzida por ácido acético para a elucidação do mecanismo de ação, no qual os animais foram tratados na dose padrão de 5 mg/kg (i.p.) e para análise anti-inflamatória do composto foi utilizado o modelo de granuloma induzido por pelotas de algodão, no qual os animais foram tratados na dose de 10 mg/kg (i.p.). O composto, não demonstrou alterar a deambulação dos animais em nenhuma das doses administradas. No ensaio de contorção a Pellucidina A conseguiu inibir em 43% o número de contorções abdominais na dose de 1 mg/kg, e 65% na dose 5 mg/kg. No teste da formalina, observou-se efeito antinociceptivo apenas dose de 5 mg/kg, com redução de 68% no tempo de lambida da pata do animal na fase inflamatória. Os animais tratados com a Pellucidina A e submetidos ao ensaio da placa-quente não demonstram possuir qualquer alteração em seu tempo de latência sobre a placa, apresentando uma resposta similar aos animais tratados apenas com a solução veículo. Para a elucidação do mecanismo de ação a Pellucidina A foi administrada na dose padrão de 5 mg/kg (i.p.) e associada com a Indometacina (5 mg/kg i.p.), o NS-398 (10 mg/kg i.p.), a cipro-heptadina (0,5 mg/kg i.p.), a naloxona (1mg/kg i.p.) e o L-NAME (5 mg/kg i.p). A Pellucidina A manifestou uma ação sinérgica quando associada com cipro-heptadina e L-NAME, apresentando uma diminuição no padrão de contorções abdominais em 97% quando associado com a cipro-heptadina e 96% com L-NAME. Na análise da ação da Pellucidina A (10 mg/kg i.p.) no teste do granuloma induzido por pelotas de algodão, a Pellucidina A apresentou atividade anti-inflamatória, reduzido em 24% a formação de granuloma nos camundongos tratados. Os resultados obtidos corroboram com a hipótese de que a Pellucidina A apresenta atividade analgésica, possuindo ação periférica, capaz de interferir no processo inflamatório, atuando como um possível agonista glicocorticóide. / The Peperomia pellucida (Piperaceae) is an herbaceous plant commonly found in the American and Asian continents. In the Amazon the species is known by the name of erva-de-jabuti. This plant is used in folk medicine to treat a wide range of symptoms and diseases such as conjunctivitis, headache, asthma, gastric ulcer, inflammation and arthritis. Pellucidin A is an isolated compound of the species Peperomia pellucida and this study aimed to analyze the antinociceptive and anti-inflammatory activity of this compound, as well as to elucidate its mechanism of action. For the assays, male albino mice (25-40 g) were used, which were initially treated with pellucidin A at the doses of 0.5; 1 and 5 mg / kg (i.p.) and subjected to locomotor evaluation by the open field test and animal models of acute pain, such as acetic acid-induced abdominal writhing tests, formalin tests and the hot plate test. The acetic acid-induced abdominal contortion test was realized to elucidate the mechanism of action in which the animals were treated at the standard dose of 5 mg/kg (i.p.) and for anti-inflammatory analysis of the compound was used model of granuloma induced by pellets of cotton, in which the animals were treated in the dose of 10 mg/kg (i.p.). The compound did not show capacity to change the ambulation of the animals at any of the administered doses. In the contortion test, pellucidin A was able to inhibit the number of abdominal writhings in 43% at the dose of 1 mg/kg, and 65% at the dose of 5 mg/kg. In the formalin test, an antinociceptive effect was observed at the dose of 5 mg/kg, with a 68% reduction in the lymph time of the animal's paw in the inflammatory phase, showing a similar response to Indomethacin used at a dose of 10 mg/kg as positive control for this phase. Animals treated with pellucidin A and subjected to the hot plate assay did not show any change in their latency time on the plate, showing a similar response to the animals treated just with the vehicle solution. For the elucidation of the action mechanism, the pellucidin A was administered at the standard dose of 5 mg/kg (i.p.) and associated with Indomethacin (5 mg/kg i.p.), NS-398 (10 mg/kg i.p.) cyproeptadine (0.5 mg/kg i.p.), naloxone (1 mg/kg i.p.) and L-NAME (5 mg/kg i.p.). The pellucidin A has shown a synergistic action when associated with cyproeptadine and L-NAME, with a decrease in the pattern of abdominal writhing by 97% when associated with cyproheptadine and 96% with L-NAME. In the analysis of the action of pellucidin A (10 mg/kg i.p.) in the granuloma test induced by cotton pellets, pellucidin A presented anti-inflammatory activity, reduced granuloma formation in 24% in the treated mice. The results confirm the hypothesis that pellucin A presents analgesic activity capable of interfering in the inflammatory process, acting as a possible glucocorticoid agonist.
38

Interacciones homólogas y heterólogas in vitro de gametos porcinos, bovinos y humanos y sus aplicaciones en el estudio de la fecundación

Cánovas Bernabé, Sebastián 08 May 2007 (has links)
La interacción entre gametos es crucial para la fecundación. La zona pelúcida (ZP) se considera responsable de bloquear la polispermia, pero in vitro estas funciones no son totalmente eficientes. La polispermia es frecuente en fecundación in vitro (FIV) en porcino y bovino, mientras que la interacción heteróloga espermatozoide-ovocito ha sido demostrada. Los objetivos fueron estudiar el bloqueo de la polispermia para mejorar los resultados de FIV e investigar las interacciones heterólogas entre espermatozoide humano y ovocito porcino. Los resultados demuestran que se produce endurecimiento de la ZP de ovocitos bovinos y porcinos de forma previa a la fecundación, utilizando DTSP o fluido oviductal bovino. Cuando se utilizan estos ovocitos en FIV aumenta la monospermia y el rendimiento final. En las interacciones heterólogas los espermatozoides humanos pueden unirse a ZP porcina y sufren la reacción acrosómica, pero no penetran los ovocitos sin ZP. En ICSI activan el ovocito y forman pronúcleos. / The interaction between gametes is crucial to fertilization. The zona pellucida (ZP) is responsible to block of polyspermy, but in vitro these functions are not efficient. The polyspermy is frequently in bovine and porcine in vitro fecundation. Besides the heterologous interaction between spermatozoa-oocyte had been described. The aims were study the block of polyspermy to improve the output of IVF and research the heterologous interactions between human spermatozoa and porcine oocyte.The results show that there is hardening of bovine and porcine ZP previously at fertilization, in vivo and using DTSP or bovine oviductal fluid. When these oocytes are used in IVF improve the monospermy and the output. In heterologus interactions the human spermatozoa could bind to porcine ZP and it triggers the acrosome reaction, but not penetration in ZP-free oocyte was observed. In ICSI the oocyte activation and
39

Life history and population dynamics of Eastern Sand Darter (Ammocrypta pellucida) in the lower Thames River, Ontario

Finch, Mary January 2009 (has links)
Eastern Sand Darter (Ammocrypta pellucida) is listed as Threatened under the Canadian Species at Risk Act. Canadian populations are declining primarily due to the siltation of sandy depositional areas, the preferred habitat of the species. Little other relevant biological information is available for most Canadian populations and only limited information is available for populations in the United States. To supplement the paucity of information, this study collected biological information on A. pellucida during field surveys in 2006- 2007 from 10 sites located around the Big Bend Conservation Area in the lower Thames River, Ontario, Canada. Collected data were used to estimate critical life history traits including: longevity, fecundity, clutch size and number, growth, survival, age-at-first-maturity and cohort age structure. Longevity was 3+ years, with age-at-first-maturity being 1+ for both sexes. A minimum of 2 clutches, were laid per year with an average clutch size of 71 eggs. Average density within in the study area was 0.36 ± 0.11 A. pellucida/m². Quantitative comparison of lower Thames River biological information with a more southerly A. pellucida population in the Little Muskingum River, Ohio, demonstrated little latitudinal variation between the populations. Data comparison suggests that localized environmental factors are affecting biological characteristics, in particular water temperature that may be controlled by differences in riparian cover and/or groundwater input. Field derived life history information was used to create a Leslie matrix model which was used for population viability analysis. Perturbation analyses of reproductive scenarios involving changes in clutch numbers and size and age-at-first maturity found large variations in the finite rate of population growth. Elasticity analyses further indicated that 0+ survival and 1+ fertility were the limiting life history parameters. Thus allowing fish to survive until first reproduction would have the largest overall impact on improving population viability. Inclusion of environmental stochasticity in the model facilitated estimation of extinction probabilities in the range of 0.13 to 0.21 within 100 years. Based on the above, it is recommended that management activities for protection and restoration of A. pellucida focus on habitat protection of nursery and spawning areas.
40

Life history and population dynamics of Eastern Sand Darter (Ammocrypta pellucida) in the lower Thames River, Ontario

Finch, Mary January 2009 (has links)
Eastern Sand Darter (Ammocrypta pellucida) is listed as Threatened under the Canadian Species at Risk Act. Canadian populations are declining primarily due to the siltation of sandy depositional areas, the preferred habitat of the species. Little other relevant biological information is available for most Canadian populations and only limited information is available for populations in the United States. To supplement the paucity of information, this study collected biological information on A. pellucida during field surveys in 2006- 2007 from 10 sites located around the Big Bend Conservation Area in the lower Thames River, Ontario, Canada. Collected data were used to estimate critical life history traits including: longevity, fecundity, clutch size and number, growth, survival, age-at-first-maturity and cohort age structure. Longevity was 3+ years, with age-at-first-maturity being 1+ for both sexes. A minimum of 2 clutches, were laid per year with an average clutch size of 71 eggs. Average density within in the study area was 0.36 ± 0.11 A. pellucida/m². Quantitative comparison of lower Thames River biological information with a more southerly A. pellucida population in the Little Muskingum River, Ohio, demonstrated little latitudinal variation between the populations. Data comparison suggests that localized environmental factors are affecting biological characteristics, in particular water temperature that may be controlled by differences in riparian cover and/or groundwater input. Field derived life history information was used to create a Leslie matrix model which was used for population viability analysis. Perturbation analyses of reproductive scenarios involving changes in clutch numbers and size and age-at-first maturity found large variations in the finite rate of population growth. Elasticity analyses further indicated that 0+ survival and 1+ fertility were the limiting life history parameters. Thus allowing fish to survive until first reproduction would have the largest overall impact on improving population viability. Inclusion of environmental stochasticity in the model facilitated estimation of extinction probabilities in the range of 0.13 to 0.21 within 100 years. Based on the above, it is recommended that management activities for protection and restoration of A. pellucida focus on habitat protection of nursery and spawning areas.

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