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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.
11

Caracterização espermáticas na subfamília Cichlinae (Perciformes : Chlidae) e suas implicações filogenéticas /

Ortiz, Rinaldo José. January 2012 (has links)
Orientador: Irani Quagio-Grassiotto / Coorientador: Ricardo Cardoso Benine / Banca: Cesar Martins / Banca: Francisco Langeani Neto / Banca: José Lino Neto / Banca: Mary Anne Heidi Dolder / Resumo: Cichlidae é a maior família de peixes não-Ostariophysi de água doce, e uma das maiores famílias de vertebrados. De ampla distribuição mundial, os gêneros neotropicais atualmente foram elevados a status de subfamília, Cichlinae. As hipóteses existentes para as relações de parentesco em Cichlinae, tendo por base características osteológicas e de partes moles e mais recentemente dados moleculares, não são congruentes entre si. Sabe-se que as características espermáticas contem informações filogenéticas e podem ser úteis no estudo do relacionamento entre as espécies. Neste estudo, descreveu-se a espermiogênese e os caracteres ultraestruturais dos espermatozóides de membros da subfamília Cichlinae e da subfamília Pseudocrenilabrinae. Os dados resultantes foram utilizados numa análise filogenética, que comparada as proposta pré-existentes, recupera alguns dos grupos mais proximamente relacionados, caso dos gêneros Retroculus e Cichla. Estes gêneros são reconhecidos como basais dentro da subfamília. Outro grupo que se mantém, é o formado por Andinoacara rivulatus, Cichlasoma portalegrense e Aequidens tetramerus, membros da tribo Cichlasomatini. Além disso, a tribo Cichlasomatini ocupa posição derivada no cladograma, como em hipóteses anteriores / Abstract: Cichlidae is the largest family of non-Ostariophysi freshwater fish and one of the largest family of vertebrates. With a worldwide distribution, the Neotropical genera have been now elevated to a subfamily status, Cichlinae. The existing hypotheses for the phylogenetic relationships in Cichlinae, based on osteological features and soft tissue and more recently on molecular data, are not congruent. It is known that the spermatics characteristics contains phylogenetic information and can be useful in the studies of the relationship between species. Then, this study described the spermiogenesis and sperm ultrastructural characterics from some members of the Neotropical subfamily Cichlinae and from the African, Pseudocrenilabrinae. The data was used in a phylogenetic analysis, that when compared to pre-existing proposals, recovers some of the most closely related genera, for example, Cichla and Retroculus. These genera are recognized as basal within the subfamily Cichlinae. Another group that remains, it is that formed by Andinoacara rivulatus, Cichlasoma portalegrense and Aequidens tetramerus, members of the tribe Cichlasomatini. The tribe Cichlasomatini occupies a derivative position in the cladograma / Doutor
12

Biologia reprodutiva de fêmeas de laetacara araguaiae (labriformes: cichlidae)

Silva, Amanda Pereira dos Santos [UNESP] 21 February 2014 (has links) (PDF)
Made available in DSpace on 2014-11-10T11:09:42Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-02-21Bitstream added on 2014-11-10T11:58:44Z : No. of bitstreams: 1 000794186.pdf: 3889062 bytes, checksum: 2cc9d4ef4d96b18c583d8f9cc3727adf (MD5) / Laetacara araguaiae é uma espécie de ciclídeo sul-americano descrito na bacia do rio Araguaia, São Miguel do Araguaia, Goiás, Brasil por Ottoni e Costa (2009). A descrição das fases reprodutivas vem sendo realizada há algum tempo com a análise do ciclo reprodutivo anual, que se baseia nas fases de maturação gonadal de espécies analisadas. O objetivo do trabalho foi descrever morfologicamente o ciclo reprodutivo de fêmeas de L. araguaiae. Foram coletadas 80 fêmeas de L. araguaiae, no período abril/2012 a março/2013, no rio Dois Córregos, Selvíria, Mato Grosso do Sul, Brasil. Os ovários foram processados, utilizando-se técnicas para microscopia de luz e microscopia eletrônica de transmissão. Ainda foram identificadas as fases do ciclo reprodutivo que se aplicam as fêmeas, índice gonadossomático (IGS) e tamanho da primeira maturação ovariana. A oogênese apresentou epitélio germinativo com três tipos de oogônias e oócitos em fase de prófase da meiose para a formação dos folículos ovarianos. Crescimento primário com a presença de oócitos pré-vitelogênicos e oócitos alvéolos corticais e crescimento secundário ou vitelogênese, caracterizado pela deposição inicial de grânulos de vitelo. O evento, que caracteriza o estágio de maturação é a migração do núcleo para a periferia do oócito em direção à micrópila. O complexo folicular sofreu modificações morfológicas ao longo dos estágios dos oócitos. Alem disso, para Laetacara araguaiae foram definidas cinco fases reprodutivas ao longo do ano: imaturo, desenvolvimento, apto a desova, regressão e regeneração. O comprimento médio da primeira maturação ovariana foi estimado em 2,0 cm de comprimento padrão. Os indivíduos maduros (aptos à desova) foram capturados a partir de setembro que coincidem com as estações de primavera e verão. O IGS apresentou valores médios elevados na fase de apto a desova (4,528) e os menores valores médios ... / Laetacara araguaiae is a species of south American ciclideo described in the Araguaia river basin, São Miguel do Araguaia, Goias, Brazil by Ottoni and Costa (2009). The description of reproductive phases is being performed some time ago with the analysis of the annual reproductive cycle, that is based on stages of gonadal maturation of analyzed species. The objective of this work was to describe morphologically the reproductive cycle of female L. araguaiae. Were collected from 80 females of L. araguaiae, in the period April/2012 to March/2013, in Two Streams, river Selviria, Mato Grosso do Sul, Brazil. The ovaries were processed, using techniques for light microscopy and transmission electron microscopy. Even were identified phases of the reproductive cycle that apply to females, gonadossomatico index (GSI) and size of first ovarian maturation. The oogenesis presented germinative epithelium with three types of oogonias and oocytes in phase of profase of meiosis for the formation of the ovarian follicles. Primary Growth with the presence of oocytes pre-vitelogenicos and oocytes cortical alveoli and secondary growth or vitelogenese, characterized by initial deposition of granules of yolk. The event which characterizes the maturation stage is the migration from the nucleus to the periphery of the oocyte toward through. The follicular suffered complex morphological changes along the stages of oocytes. In addition, for Laetacara araguaiae were defined five reproductive phases throughout the year: immature, development, able to spawning, regression and regeneration. The average length of first ovarian maturation was estimated at 2.0 cm standard length. The mature individuals (able to spawn) were captured from September to coincide with the seasons of spring and summer. The IGS showed high average values in phase of able to spawn (4,528) and the lowest average values in immature (0.502). The seasons of the year in which the individual is able ...
13

Efeito da estocagem a curto prazo e da temperatura sobre gametas de jundiá, Rhamdia quelen (Quoy & Gaimard, 1824)

Sanches, Eduardo Antônio [UNESP] 21 August 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-08-21Bitstream added on 2014-06-13T18:08:12Z : No. of bitstreams: 1 sanches_ea_me_jabo.pdf: 1805723 bytes, checksum: 57436a068bd303d903231a9efc47438f (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / O trabalho foi conduzido com o objetivo de avaliar o efeito da temperatura de estocagem a curto prazo e da temperatura da água sobre os ovócitos e sêmen de jundiá, Rhamdia quelen. O experimento foi realizado em três etapas: (1) avaliar a qualidade dos ovócitos após estocagem e ativação em diferentes temperaturas; (2) padronizar a utilização de análise espermática computadorizada por meio de softwares livres; (3) avaliar os parâmetros espermáticos computadorizados após estocagem e ativação em diferentes temperaturas. Para a primeira, utilizou-se um delineamento experimental fatorial no tempo (5×3×3×3), com os tratamentos realizados em triplicata a cada 48h, na exposição de ovócitos nas temperaturas de 15; 25 e 35ºC e, ativados com água à 15; 25 e 35ºC cada, nos períodos de: 0; 45; 90; 135 e 180 minutos pós-coleta. A segunda etapa foi realizada através da captura de vídeos da movimentação espermática pelo software AMCAP, a uma taxa de 60 frames por segundo, processados no software VIRTUALDUB e analisados no software IMAGEJ por meio do aplicativo CASA. Os seguintes parâmetros foram analisados: taxa de motilidade espermática (MOT), velocidade curvilinear (VCL), velocidade média do deslocamento (VMD), velocidade em linha reta (VLR), linearidade (LIN), balanço (BAL) e freqüência de batimentos (FBAT). Os parâmetros espermáticos foram avaliados em um segundo de imagem nos tempos de 15, 25 e 35 segundos após a ativação espermática. Para a terceira etapa foi utilizado um delineamento experimental fatorial no tempo semelhante à primeira ,com 13 tempos de avaliação pós-coleta: 0; 2; 4; 6; 8; 10; 12; 16; 20; 24; 32; 40 e 48 horas. Os tratamentos foram realizados em triplicata e em protocolos sequenciais a cada 50 horas avaliando-se os parâmetros obtidos na segunda etapa. Estes foram submetidos às análises de correlação (Pearson)... / The study was conducted to evaluate the effect of temperature of storage in the short-term and the temperature of the water on the oocytes and sperm of jundiá, Rhamdia quelen. The experiment was conducted in three stages: (1) assess the quality of oocytes after storage and activation at different temperatures; (2) standardize the use of computerized sperm analysis by software free, (3) evaluate the computerized sperm parameters after storage and activation at different temperatures. For the first, was used a factorial experimental design in time (5×3×3×3), with treatments performed in triplicate every 48 hours, the exposure of oocytes at temperatures of 15, 25 and 35 C, and activated with water to 15, 25 and 35 C each, in the periods of: 0; 45; 90; 135 and 180 minutes post-collection. The second stage was performed by video capture of the movement of sperm through AMCAP software at a rate of 60 frames per second, processed and analyzed in VirtualDub software and ImageJ software using the CASA application. The following parameters were analyzed: rate of sperm motility (MOT), velocity curvilinear (VCL), velocity average path (VAP), velocity straight line (VSL), linearity (LIN), wobble (WOB), beating cross frequency (BCF). The sperm parameters were evaluated in a second image in the times of 15, 25 and 35 seconds after sperm activation. For the third step we used a factorial experimental design similar to the first in time, with 13 times of evaluation post-collection: 0; 2; 4; 6; 8; 10; 12; 16; 20; 24; 32; 40 and 48 hours. The treatments were performed in triplicate and sequencing protocols to be evaluated every 50 hours if the parameters obtained in the second stage. These were submitted to analysis of correlation (Pearson). The significant parameters (P<0.05) were summarized by the principals components analysis. For the first stage interaction (P<0.05) between time and temperature... (Complete abstract click electronic access below)
14

Biologia reprodutiva de fêmeas de laetacara araguaiae (labriformes: cichlidae) /

Silva, Amanda Pereira dos Santos. January 2014 (has links)
Orientador: Rosicleire Veríssimo Silveira / Banca: Igor Paiva Ramos / Banca: Elizabeth Romagosa / Resumo: Laetacara araguaiae é uma espécie de ciclídeo sul-americano descrito na bacia do rio Araguaia, São Miguel do Araguaia, Goiás, Brasil por Ottoni e Costa (2009). A descrição das fases reprodutivas vem sendo realizada há algum tempo com a análise do ciclo reprodutivo anual, que se baseia nas fases de maturação gonadal de espécies analisadas. O objetivo do trabalho foi descrever morfologicamente o ciclo reprodutivo de fêmeas de L. araguaiae. Foram coletadas 80 fêmeas de L. araguaiae, no período abril/2012 a março/2013, no rio Dois Córregos, Selvíria, Mato Grosso do Sul, Brasil. Os ovários foram processados, utilizando-se técnicas para microscopia de luz e microscopia eletrônica de transmissão. Ainda foram identificadas as fases do ciclo reprodutivo que se aplicam as fêmeas, índice gonadossomático (IGS) e tamanho da primeira maturação ovariana. A oogênese apresentou epitélio germinativo com três tipos de oogônias e oócitos em fase de prófase da meiose para a formação dos folículos ovarianos. Crescimento primário com a presença de oócitos pré-vitelogênicos e oócitos alvéolos corticais e crescimento secundário ou vitelogênese, caracterizado pela deposição inicial de grânulos de vitelo. O evento, que caracteriza o estágio de maturação é a migração do núcleo para a periferia do oócito em direção à micrópila. O complexo folicular sofreu modificações morfológicas ao longo dos estágios dos oócitos. Alem disso, para Laetacara araguaiae foram definidas cinco fases reprodutivas ao longo do ano: imaturo, desenvolvimento, apto a desova, regressão e regeneração. O comprimento médio da primeira maturação ovariana foi estimado em 2,0 cm de comprimento padrão. Os indivíduos maduros (aptos à desova) foram capturados a partir de setembro que coincidem com as estações de primavera e verão. O IGS apresentou valores médios elevados na fase de apto a desova (4,528) e os menores valores médios ... / Abstract: Laetacara araguaiae is a species of south American ciclideo described in the Araguaia river basin, São Miguel do Araguaia, Goias, Brazil by Ottoni and Costa (2009). The description of reproductive phases is being performed some time ago with the analysis of the annual reproductive cycle, that is based on stages of gonadal maturation of analyzed species. The objective of this work was to describe morphologically the reproductive cycle of female L. araguaiae. Were collected from 80 females of L. araguaiae, in the period April/2012 to March/2013, in Two Streams, river Selviria, Mato Grosso do Sul, Brazil. The ovaries were processed, using techniques for light microscopy and transmission electron microscopy. Even were identified phases of the reproductive cycle that apply to females, gonadossomatico index (GSI) and size of first ovarian maturation. The oogenesis presented germinative epithelium with three types of oogonias and oocytes in phase of profase of meiosis for the formation of the ovarian follicles. Primary Growth with the presence of oocytes pre-vitelogenicos and oocytes cortical alveoli and secondary growth or vitelogenese, characterized by initial deposition of granules of yolk. The event which characterizes the maturation stage is the migration from the nucleus to the periphery of the oocyte toward through. The follicular suffered complex morphological changes along the stages of oocytes. In addition, for Laetacara araguaiae were defined five reproductive phases throughout the year: immature, development, able to spawning, regression and regeneration. The average length of first ovarian maturation was estimated at 2.0 cm standard length. The mature individuals (able to spawn) were captured from September to coincide with the seasons of spring and summer. The IGS showed high average values in phase of able to spawn (4,528) and the lowest average values in immature (0.502). The seasons of the year in which the individual is able ... / Mestre
15

Aspekte van die spermatologie van die tiervis (Hydrocynus vittatus) en die kriobewaring van semen van geselekteerde varswatervissoorte

Steyn, Gerhardus Jacobus 10 September 2014 (has links)
M.Sc. (Zoology) / This investigation is divided into two sections. Section A deals with aspects of the spermatology of the tiger fish and section B deals with the cryopreservation of spermatozoa of selected freshwater fish species.
16

Sexual selection by female choice in guppies (Poecilia reticulata)

Brooks, Robert Clinton January 1996 (has links)
A thesis submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg in fulfillment of the requirement for the degree of Doctor of Philosophy JOHANNESBURG January 1996 / I investigated some evolutionary implications of female mate choice in a feral population of guppies (Poecllia reticultuai. I performed correlative and manipulative experiments to establish the relationship between female mate choice and other sexually selective forces including iutermale aggression and sneak copulation, and the exaggerated secondary sex characters (ornaments) of male guppies. Orange (carotenoid) ornamentation is the best predictor of male attractiveness and mating success, a relationship which held under manipulation. Black (melanin) is sometimes correlated with male mating success. Mnnipulatiug the black area of males reveals that it is important to male attractiveness, and this appears to be in the form of a signal amplifier of male orangeness. This is the fi.st experimental evidence for a visual signal amplifier. For both orange and black areas, the relationship between absolute area and fluctuating asymmetry is positive and significant, suggesting that neither is n signal of male condition. These results arc Interpreted in the context of theories of the evolution of multiple male ornaments. Females are able to express their preference for orange with the first mature male they ever encounter, uuggestlng an important role for genetic determination in female preferences. This is corroborated by high repeatability of female mate choice behaviour. Experience modifies a female's preferences as she is able to adjust her response to a male in relation to the ornamentation of (at least) the previous male she saw. Mate copying has no mensurable effect on the outcome of female mate choice decisions. / MT2016
17

Reproductive Development of Female Bonefish (Albula spp.) from the Bahamas

Unknown Date (has links)
Bonefish (Albula spp.) support an economically important sport fishery, yet little is known regarding the reproductive biology of this genus. Analysis of oocytes histology and sex hormone levels was conducted on wild female bonefish sampled during and outside the spawning season in Grand Bahama, Central Andros, and South Andros, The Bahamas to assess reproductive state. Bonefish are commonly found along shallow water flats, or in pre-spawn aggregations (PSA) during spawning months. 17β-estradiol levels suggest vitellogenic consistency between habitats. However, fish are more reproductively developed at PSA based on the occurrence of larger, more prevalent vitellogenic oocytes and evidence of final maturation. Variability in hormone levels and spawning readiness existed between Grand Bahama and Andros PSAs, suggesting peak spawning may differ by region. Findings from this study will contribute baseline data to the captive bonefish restoration project at Harbor Branch Oceanographic Institute and to the limited ecological data regarding bonefish reproduction. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2018. / FAU Electronic Theses and Dissertations Collection
18

Crioconservação de embriões de peixes neotropicais /

Costa, Raphael da Silva. January 2013 (has links)
Orientador: Alexandre Ninhaus Silveira / Banca: George Shigueki Yasui / Banca: Danilo Pedro Streit Junior / Resumo: A criopreservação é uma ferramenta biotecnológica que permite congelar e estocar, por longos períodos células, tecidos, órgãos e embriões; contudo, o sucesso desta tecnologia, para peixes, é bem estabelecida apenas para as células germinativas masculinas, conservando assim, parcialmente material genético de uma população. Desta forma objetivou-se estabelecer um eficaz protocolo de crioconservação para embriões de peixes neotropicais, visando à preservação total da bagagem genética da espécie. Utilizou-se como modelo biológico embriões de Prochilodus lineatus, que foram avaliados quanto a sua sensibilidade ao frio, à toxicidade dos crioprotetores dimetil formamida, dimetil sulfóxido, propileno glicol e glicerol, aos protocolos de resfriamento nos estágios de gastrulação e organogênese com seis e vinte somitos e a vitrificação nos estágios de organogênese com seis e vinte somitos. As amostras foram fixadas em solução de paraformaldeído a 4% e glutaraldeído a 2% em tampão fosfato Sorensen 0,2 M pH 7,2, incluídos em metacrilato glicol, seccionados a 3 e 5 µm de espessura e corados com hematoxilina-eosina, azul de toluidína, P.A.S. e metanil yellow. A fase embrionária de organogênese com 20 somitos foi a mais resistente ao frio e a toxicidade dos crioprotetores. Apesar das altas taxas de larvas vivas nos tratamento de resfriamento, em nenhum dos protocolos propostos obteve-se êxito na preservação das estruturas embrionárias, sendo verificado graves danos morfológicos como corpo reduzido e com sinuosidades, nadadeiras com crescimento desordenado das células, alta concentração de células necróticas na região do encéfalo, má-formação das vesículas ópticas e óticas, má-formação das narinas, fusão desordenada dos mioblastos, retração do vitelo, espaços entre as células provocadas... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Cryopreservation is a biotechnological tool that allows you to freeze and store cells, tissues, organs and embryos for long periods; however, the success of this technology, to the fish, it is established only from the male germ cells, preserving, partly the material of a population. Therefore the purpose was to establish an effective protocol of cryopreservation to embryos of neotropical fish, in order to preserv all the genetic load of the species. As biological model of this research it was used Prochilodus lineatus type of embryos, which were evaluated regarding to their sensibility to cold temperatures, the toxicity of cryoprotectants dimethyl formamide, dimethyl sulfoxide, propylene glycol and glycerol, also the protocols of cooling down on the gastrulation and organogenesis stages with six and twenty somites, and the vitrification on the organogenesis stages with six and twenty somites. The samples were fixed in solutions with 4% of paraformaldehyde and 2% of glutaraldehyde, Sorensen phosphate with 0.2 M pH 7.2, included in glycol methacrylate, sectioned at 3 and 5 µm of thickness and stained with hematoxylin-eosin, Blue toluidine, PAS and Metanil Yellow. The embryonic phase of organogenesis with 20 somites was the most resistant to cold and toxicity of cryoprotectants. Despite of the high rates of alived larvae founded in the cooling treatment, none of the proposed protocols succedded in the preservation of the embryonic structures, it could be seen severe morphological damages as reduction in the body and sinuous in the forms, with fins disorderly cell growth, high concentration of necrotic cells on region of the brain, malformation of the ear and eyes vesicle, malformation of the nostrils, disorderly fusion of the myoblasts, retraction of the yolk, spaces between cells caused by the formation of ice crystals... (Complete abstract click electronic access below) / Mestre
19

Growth and reproductions of Oreochromis niloticus (L.) in tropical aquatic microcosms at fluctuating temperature regimes

Rwangano, F��licien 15 April 1998 (has links)
Graduation date: 1998
20

Endocrine regulation of final oocyte maturation and sex differentiation in salmonids

Fitzpatrick, Martin S. 29 May 1990 (has links)
Sexual maturation and sex differentiation comprise facets of a common theme: reproduction. The endocrine system regulates many of the critical physiological processes necessary for reproduction and offers a framework within which technologies can be developed for controlling sexual maturation and sex differentiation. The studies described in this thesis were undertaken to improve the understanding of the endocrine control of these critical stages of development in salmonids. Final ovarian maturation in salmon is accompanied by dynamic changes in plasma hormone levels. Ovulation can be accelerated through the use of hormones such as gonadotropin releasing hormone or its analogs (GnRHa). The effectiveness of GnRHa often depends on the timing of treatment. To determine if plasma concentrations of steroids can be used to predict the sensitivity of adult female coho salmon (Oncorhynchus kisutch) to GnRHa, circulating levels of testosterone, 17α,20β-dihydroxyprogesterone (DHP), and estradiol were measured before and after injection with GnRHa to accelerate ovulation. We found that high levels of testosterone were predictive of early response of coho salmon to GnRHa treatment. The correlation between testosterone and ovulatory response to GnRHa suggested a possible functional relation. However. implantation or injection of testosterone. 17α-methyltestosterone (MT), or the antiandrogen, cyproterone acetate (CA), before or with GnRHa treatment did not affect the ovulatory response of coho or chinook salmon ( 0. tshawytscha) to GnRHa. Chinook salmon treated with MT alone had accelerated ovulation in comparison to controls. If steroids are involved in sex differentiation. steroids must be produced early in development. In vitro production of steroids in both coho salmon and rainbow trout (0. mykiss) was assessed from hatch through sex differentiation. Cortisol, androstenedione, testosterone, and estradiol were produced just after hatching by tissue explants that contained anterior kidneys and gonads of coho salmon. To circumvent the problem of not knowing the sex of individuals until after sex differentiation, single-sex populations of rainbow trout were produced by gynogenesis or androgenesis. Tissue explants produced more androstenedione than testosterone or estradiol. More androgens were produced by testes and more estradiol was produced by ovaries within 6 to 10 weeks of hatching. Dietary treatment with estradiol or MT inhibited gonadal steroid secretion. Electrophoresis of gonadal homogenates from salmonids revealed several sex-specific bands. In particular, a prominent band of about 50,000 daltons was apparent in ovaries but not testes. Production of sex-specific proteins may be affected by dietary steroid treatment. / Graduation date: 1991

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