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The population dynamics and fishery productivity of snapper, Chrysophrys auratus, in South Australia are strongly driven by inter-annual variation in recruitment. This variable recruitment produces the occasional strong year-class which, over a number of years, results in a cycle of increasing and then decreasing biomass. The aim of this study was to develop an understanding of the recruitment dynamics of snapper through a study of the reproductive biology of adults, as well as the biology and ecology of 0+ recruits. Field sampling was done through 2006 to 2008 in northern Spencer Gulf, the region that generally contributes the majority of South Australia’s snapper catch. The recruitment of 0+ snapper was measured from a study of inter-and intra- annual patterns of distribution and abundance. This was done using two independent trawl sampling regimes, one using a beam trawl and the other an otter trawl, at different times in the settlement season. There was considerable inter-annual variation in abundance of 0+ fish of up to two orders of magnitude and, in some years, almost no recruitment was observed. The spatial pattern of dispersion of recruits was clumped and consistent between years; one area, Western Shoal, always produced the highest catches indicating that it is an important nursery. The effects of the timing of spawning and water temperature on growth patterns of the 0+ snapper collected in the trawl sampling were studied to determine possible impacts on recruitment processes. Growth was studied from age/length regressions and by measuring the widths of microincrements in the sagittal otoliths. Sub-surface water temperature was also logged in the region. Growth rate varied inter- and intra-annually but was not limited by temperature in the pre-settlement period. However, post-settlement growth rate was significantly correlated with water temperature and fish exhibited a dramatic slowing of growth as temperature declined in autumn. Later spawned fish were considerably smaller than earlier spawned fish of the same age, which may have implications for post-settlement survival. The reproductive biology of snapper was studied to determine if annual variation in recruitment was related to egg production. Reproductive samples from northern Spencer Gulf were collected over three seasons (2005/06, 2006/07 and 2007/08) and were analysed macro- and microscopically. Spawning activity was determined by calculating estimates of spawning fraction and batch fecundities. The onset of spawning occurred in November but varied between years and corresponded with times when water temperature was between 18 and 20ºC. The length of the spawning season also differed between years. In each year the peak spawning activity occurred during December when fish spawned almost daily. Spawning frequency and relative batch size did not differ between the first two spawning seasons but, in the third season, batch size was considerably greater and spawning fraction lower. However, recruitment was considerably more variable than the annual differences in spawning output could explain. This indicates that mortality processes during the planktonic or early post-settlement period are important in the recruitment dynamics of snapper. The impact of water temperature, lunar cycle and tide on the timing and strength of recruitment was investigated. Pre-settlement duration, spawn dates and settlement dates were determined from the microstructure of the sagittal otoliths of 0+ snapper. The patterns of successful spawning and settlement were determined by back-calculating to the day on which individual recruits were spawned and settled. The frequency distributions of these dates were compared with water temperature, lunar periodicity and the temporal variation in spawning. There was considerable variation within a season in the timing and magnitude of successful recruitment. Strongest recruitment resulted from spawning during December and January on days when water temperatures were between 21 and 23ºC but spawning on days in this range did not necessarily result in recruitment. Pre-settlement duration was unaffected by water temperature. Some evidence of lunar periodicity was detected in both the spawn and settlement date frequencies. Importantly, the spawn date frequency distributions of successful 0+ recruits did not correspond with the measured spawning activity of adults as considerable portions of the spawning season in each year did not produce successful recruits. These results indicated that spawning output and water temperature cannot explain the observed magnitude in recruitment variation. Food availability for 0+ snapper has been implicated in their patterns of distribution and abundance in New Zealand and Japan. Stomach contents of 0+ snapper were described as an initial step in developing some understanding of the dispersion of 0+ recruits. In spite of their generalist feeding habit, in the area of highest abundance (Western Shoal), snapper took considerably more polychaetes than elsewhere in northern Spencer Gulf. If polychaetes are more abundant at Western Shoal, this could explain the higher density of 0+ snapper there but insufficient information was available on these animals for northern Spencer Gulf to address this hypothesis. Food availability and/or quality may influence the distribution of 0+ recruits. The multi-species collections from the beam trawls were described to develop an understanding of the spatial dispersion of recruits and their habitat associations. 0+ snapper co-occurred with an assemblage that was characterised by fish and invertebrate species that are associated with mud/soft bottom, but they never occurred with the assemblage of species associated with seagrass, even when recruitment was strongest. This association partly explains the observed distribution pattern, but not all areas of mud/soft bottom had 0+ recruits, even in strong recruitment years. In northern Spencer Gulf, seagrass areas could be excluded from future snapper recruitment surveys. The recruitment dynamics of snapper in northern Spencer Gulf were characterised by dramatic inter-annual variation but a consistent pattern of dispersion. 0+ snapper were concentrated in a few small areas in northern part of the study region. One of these areas, Western Shoal, appears to be very important as a nursery for snapper. Furthermore, the pattern of 0+ snapper dispersion was independent of recruitment strength. The potential magnitude of 0+ snapper recruitment, set by egg production, was altered by mortality during the early life history. Some of this mortality was related to temperature regimes at the time of spawning but this did not explain all the variation in the magnitude and timing of recruitment. Snapper spawning occurred at times with suitable temperature conditions but recruitment did not always result. This indicates the presence of other factor(s) that have substantial influences on mortality in the early life history. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1374397 / Thesis (Ph.D.) - University of Adelaide, School of Earth and Environmental Sciences, 2009

The population dynamics and fishery productivity of snapper, Chrysophrys auratus, in South Australia are strongly driven by inter-annual variation in recruitment. This variable recruitment produces the occasional strong year-class which, over a number of years, results in a cycle of increasing and then decreasing biomass. The aim of this study was to develop an understanding of the recruitment dynamics of snapper through a study of the reproductive biology of adults, as well as the biology and ecology of 0+ recruits. Field sampling was done through 2006 to 2008 in northern Spencer Gulf, the region that generally contributes the majority of South Australia’s snapper catch. The recruitment of 0+ snapper was measured from a study of inter-and intra- annual patterns of distribution and abundance. This was done using two independent trawl sampling regimes, one using a beam trawl and the other an otter trawl, at different times in the settlement season. There was considerable inter-annual variation in abundance of 0+ fish of up to two orders of magnitude and, in some years, almost no recruitment was observed. The spatial pattern of dispersion of recruits was clumped and consistent between years; one area, Western Shoal, always produced the highest catches indicating that it is an important nursery. The effects of the timing of spawning and water temperature on growth patterns of the 0+ snapper collected in the trawl sampling were studied to determine possible impacts on recruitment processes. Growth was studied from age/length regressions and by measuring the widths of microincrements in the sagittal otoliths. Sub-surface water temperature was also logged in the region. Growth rate varied inter- and intra-annually but was not limited by temperature in the pre-settlement period. However, post-settlement growth rate was significantly correlated with water temperature and fish exhibited a dramatic slowing of growth as temperature declined in autumn. Later spawned fish were considerably smaller than earlier spawned fish of the same age, which may have implications for post-settlement survival. The reproductive biology of snapper was studied to determine if annual variation in recruitment was related to egg production. Reproductive samples from northern Spencer Gulf were collected over three seasons (2005/06, 2006/07 and 2007/08) and were analysed macro- and microscopically. Spawning activity was determined by calculating estimates of spawning fraction and batch fecundities. The onset of spawning occurred in November but varied between years and corresponded with times when water temperature was between 18 and 20ºC. The length of the spawning season also differed between years. In each year the peak spawning activity occurred during December when fish spawned almost daily. Spawning frequency and relative batch size did not differ between the first two spawning seasons but, in the third season, batch size was considerably greater and spawning fraction lower. However, recruitment was considerably more variable than the annual differences in spawning output could explain. This indicates that mortality processes during the planktonic or early post-settlement period are important in the recruitment dynamics of snapper. The impact of water temperature, lunar cycle and tide on the timing and strength of recruitment was investigated. Pre-settlement duration, spawn dates and settlement dates were determined from the microstructure of the sagittal otoliths of 0+ snapper. The patterns of successful spawning and settlement were determined by back-calculating to the day on which individual recruits were spawned and settled. The frequency distributions of these dates were compared with water temperature, lunar periodicity and the temporal variation in spawning. There was considerable variation within a season in the timing and magnitude of successful recruitment. Strongest recruitment resulted from spawning during December and January on days when water temperatures were between 21 and 23ºC but spawning on days in this range did not necessarily result in recruitment. Pre-settlement duration was unaffected by water temperature. Some evidence of lunar periodicity was detected in both the spawn and settlement date frequencies. Importantly, the spawn date frequency distributions of successful 0+ recruits did not correspond with the measured spawning activity of adults as considerable portions of the spawning season in each year did not produce successful recruits. These results indicated that spawning output and water temperature cannot explain the observed magnitude in recruitment variation. Food availability for 0+ snapper has been implicated in their patterns of distribution and abundance in New Zealand and Japan. Stomach contents of 0+ snapper were described as an initial step in developing some understanding of the dispersion of 0+ recruits. In spite of their generalist feeding habit, in the area of highest abundance (Western Shoal), snapper took considerably more polychaetes than elsewhere in northern Spencer Gulf. If polychaetes are more abundant at Western Shoal, this could explain the higher density of 0+ snapper there but insufficient information was available on these animals for northern Spencer Gulf to address this hypothesis. Food availability and/or quality may influence the distribution of 0+ recruits. The multi-species collections from the beam trawls were described to develop an understanding of the spatial dispersion of recruits and their habitat associations. 0+ snapper co-occurred with an assemblage that was characterised by fish and invertebrate species that are associated with mud/soft bottom, but they never occurred with the assemblage of species associated with seagrass, even when recruitment was strongest. This association partly explains the observed distribution pattern, but not all areas of mud/soft bottom had 0+ recruits, even in strong recruitment years. In northern Spencer Gulf, seagrass areas could be excluded from future snapper recruitment surveys. The recruitment dynamics of snapper in northern Spencer Gulf were characterised by dramatic inter-annual variation but a consistent pattern of dispersion. 0+ snapper were concentrated in a few small areas in northern part of the study region. One of these areas, Western Shoal, appears to be very important as a nursery for snapper. Furthermore, the pattern of 0+ snapper dispersion was independent of recruitment strength. The potential magnitude of 0+ snapper recruitment, set by egg production, was altered by mortality during the early life history. Some of this mortality was related to temperature regimes at the time of spawning but this did not explain all the variation in the magnitude and timing of recruitment. Snapper spawning occurred at times with suitable temperature conditions but recruitment did not always result. This indicates the presence of other factor(s) that have substantial influences on mortality in the early life history. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1374397 / Thesis (Ph.D.) - University of Adelaide, School of Earth and Environmental Sciences, 2009

Made available in DSpace on 2014-06-11T19:30:29Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-07-11Bitstream added on 2014-06-13T21:01:14Z : No. of bitstreams: 1 sanches_ea_dr_jabo.pdf: 2259186 bytes, checksum: 4918c5b558ff28f27002661990f850b9 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O objetivo do trabalho foi de adaptar metodologias de análises espermáticas e aprimorar o processo de fertilização artificial e condições de estocagem de gametas de surubim-do-paraiba, Steindachneridion parahybae: espécie de peixe criticamente ameaçada de extinção. Para tanto, foram realizados quatro ensaios experimentais: (1) validação de método e avaliação dos parâmetros espermáticos por meio de software livre. (2) determinação da dose inseminante e volume de água empregados na fertilização artificial; (3) estocagem de ovócitos in natura em quatro temperaturas ao longo de 355 minutos; (4) estocagem do sêmen in natura em quatro temperaturas ao longo 112h. Observou-se que o método de análise espermática utilizando o software de código aberto ImageJ/plugin CASA é uma ferramenta eficiente, exata, objetiva e barata, além de possibilitar uma nova perspectiva de análises em peixes nativos. As configurações estabelecidas no presente trabalho poderão servir de base para novos trabalhos relacionados às análises espermáticas do surubim-do-paraíba, bem como de outras espécies. Verificou-se que a quantidade de espermatozóides e o volume de água interferem diretamente no procedimento de fertilização artificial, com melhores resultados na utilização de 5,5×106 espermatozóides ovócito-1 e 1,0mL de água g-1 de ovócitos. Foi observado que a estocagem de ovócitos e sêmen de forma in natura não é recomendada em ambientes com temperaturas superiores a 25ºC e inferiores a 15ºC. Temperaturas intermediárias (15-25ºC) possibilitam melhores condições e prolongam a qualidade dos gametas, entretanto, recomenda-se em procedimentos de fertilização artificial da espécie, a coleta do sêmen antes que os ovócitos. Os resultados obtidos no presente trabalho além de proporcionarem aumento das... / The aim was to adapt methodologies of sperm analysis and to improve the artificial fertilization process and gamete storage conditions of surubim-of-paraiba, Steindachneridion parahybae: critically endangered fish species. So that, four experimental tests were performed: (1) validation of method and evaluation of sperm parameters using free software. (2) determination of the inseminating dose and water volume used in artificial fertilization, (3) storage of fresh oocytes into four temperatures over 355 minutes, (4) storage of fresh semen into four temperatures over 112h. It was observed that the sperm analysis method using open source software ImageJ/plugin CASA is an effective tool, accurate, objective and inexpensive, besides enables a new perspective of the analysis on the native fish. The settings established in this study could serve as a basis for further work related at sperm analysis of surubim-do-paraiba and other species. It was found that sperm quantity and water volume interfere directly in the procedure of artificial fertilization, with improved results on usage of 5.5×106 spermatozoa oocyte-1 and 1.0 ml of water g-1 of oocyte. It was observed that the fresh oocytes and sperm storage is not recommended in environments with temperatures above 25ºC and below 15ºC. Intermediate temperatures (15-25ºC) enable better results and prolong the gametes quality, however, it is recommended in the artificial fertilization procedures the semen collection before the oocytes. The results obtained in this study providing increased rates of fertilization and hatching, besides to allow gametes optimization through of the utilization of controlled manner, and with satisfactory quality for more time after collection. Besides, these results provide a basis for future research, contributing to the... (Complete abstract click electronic access below)

Made available in DSpace on 2016-02-05T18:29:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-07-30. Added 1 bitstream(s) on 2016-02-05T18:33:09Z : No. of bitstreams: 1 000855133_20160831.pdf: 290456 bytes, checksum: 044aafccda706b6ae0f47ec26dd5bfcb (MD5) Bitstreams deleted on 2016-09-01T14:08:38Z: 000855133_20160831.pdf,. Added 1 bitstream(s) on 2016-09-01T14:09:16Z : No. of bitstreams: 1 000855133.pdf: 1661454 bytes, checksum: 4c3b967d9d36329dff98179d2ab7de58 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Os objetivos deste trabalho foram avaliar o desempenho reprodutivo e o processo de diferenciação gonadal do Leporinus friderici. Primeiramente avaliamos a evolução do processo meiótico e o desempenho reprodutivo de matrizes de L. friderici induzidas com doses convencionais e reduzidas de extrato bruto de hipófise de carpa (EC) e de hormônio liberador de gonadotropinas análogo ao de mamífero associado à metoclopramida (mGnRHa + MET). Posteriormente, investigamos o início e as características do processo de diferenciação gonadal desta espécie expostos a 25 e 29°C. Para a avaliação do desempenho reprodutivo, utilizamos o EC em doses de 0,5 e 5,5mg/Kg (doses convencionais) e em doses de 0,5 e 1,0mg/Kg (doses reduzidas). Paralelamente utilizamos dose única de 40pg de mGnRHa + 20mg de MET/Kg (dose convencional) e duas doses de 4pg + 2mg; e 8pg + 4mg, de mGnRHa + MET/Kg (doses reduzidas). Para avaliação do processo de diferenciação gonadal foram amostrados aleatoriamente cinco peixes com 50, 70, 90, 110, 130, 150, 170, 190, 210 e 240 dias após eclosão (DAE), expostos a 25 e 29°C, em sistema de recirculação de água. Concluimos que embriões viáveis de L. friderici podem ser obtidos com doses reduzidas de EC, mas não com doses convencionais. Não foi possível obter embriões viáveis de L. friderici com uso de mGnRHa + MET, pelo menos com as doses e procedimentos aqui empregados, pois estes causaram baixa fertilidade, baixa eclosão e redução da qualidade dos ovos. Com relação ao processo de diferenciação gonadal, demonstramos que a temperatura mais elevada (29°C) provocou aumento no comprimento padrão (CP) e peso médio (P), intensificou a diferenciação gonadal e propiciou um maior número de fêmeas de L. friderici. Concluindo, é possível que a espécie apresente alguma toxicidade provocada pelo excesso de GnRH, hormônio luteinizante ou aos esteroides gonadais, os quais seriam transmitidos da fêmea para... / The objectives of this study were to evaluate the reproductive performance and gonadal differentiation process Leporinus friderici. First we assess the evolution of the meiotic process and the reproductive performance of L. friderici broodstock induced with conventional and lower dose of crude carp pituitary extract (EC) and mammalian gonadotropin releasing hormone analogue associated with metoclopramide (mGnRHa + MET ). Subsequently, we investigated the beginning and the characteristics of gonadal differentiation process of this species exposed at 25 and 29°C. For the evaluation of reproductive performance, we used the EC at doses of 0.5 and 5.5 mg / kg (conventional dose) and at doses of 0.5 and 1.0mg / kg (lower doses). Parallel use of a single dose of 40pg + 20mg mGnRHa MET / kg (conventional dose) and two doses of 4pg + 2mg; and 4pg + 8mg of mGnRHa + MET / kg (lower doses). For evaluation of gonadal differentiation process were randomly sampled five fish 50, 70, 90, 110, 130, 150, 170, 190, 210 and 240 days after hatching (DAE), exposed to 25 and 29°C in recirculation system water. We conclude that viable L. friderici embryos can be obtained with low doses of EC, but not with standard doses. Could not get viable embryos L. friderici with use of mGnRHa + MET, at least with the doses and procedures used here, as these caused low fertility, low hatching and reduced egg quality. With respect to gonadal differentiation process, we have demonstrated that the higher temperature (29°C) caused an increase in average weight (P) and standard length (CP), intensified gonadal differentiation and provided a greater number of females L. friderici. In conclusion, it is possible that the species has any toxicity caused by excess GnRH, luteinizing hormone or the gonadal steroids, which would be transmitted to the female embryos before the ovulation process, killing them. With the production of females, which is the genre of greater economic ... / CNPq: 141936/2012-6 / FAPESP: 2012/14901-7

Made available in DSpace on 2016-02-05T18:29:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-02-23. Added 1 bitstream(s) on 2016-02-05T18:33:29Z : No. of bitstreams: 1 000855149_20180410.pdf: 413493 bytes, checksum: e4c06095e2fe2a929c1c2ec70d19bde6 (MD5) Bitstreams deleted on 2018-04-13T13:57:56Z: 000855149_20180410.pdf,. Added 1 bitstream(s) on 2018-04-13T13:58:44Z : No. of bitstreams: 1 000855149.pdf: 2214724 bytes, checksum: 8547c0bf8fcf53aeace46818556993d9 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A nutrição de reprodutores é um dos principais aspectos relacionados com a qualidade dos ovos e larvas produzidos. Os lípidos e sua composição em ácidos graxos são considerados importantes para o desenvolvimento das gônadas, sobre hormônios gonadotrópicos e esteroidiais, bem como influencia a formação de estruturas biológicas incluindo membranas celulares. Os ácidos graxos essenciais para os peixes são o ácido linoleico e o ácido linolênico, que quando convertidos fornecem os ácidos graxos poli-insaturados, como ARA, EPA e DHA, respectivamente. O óleo de pescado marinho é considerado uma fonte ideal de ácidos graxos poli-insaturados, no entanto, os óleos vegetais são mais comumente utilizados em dietas de peixe. Assim, o objetivo deste estudo foi avaliar o desenvolvimento ovariano e o desempenho reprodutivo de jundiás (Rhamdia quelen) alimentados com diferentes fontes lipídicas (óleo de soja, óleo de peixe marinho, óleo de palma refinado e a mistura dos três óleos). As fontes lipídicas não influenciaram no desenvolvimento do ovário, nos níveis de estradiol e 17α-hidroxyprogesterona, e nos índices gonadossomáticos. No entanto, o ácido graxos influenciaram no perfil de ácidos encontrados no fígado, gônadas e oócitos. Adicionalmente dietas 'a base de o óleo de palma resultou em melhores taxas de fertilização, sendo recomendado sua utilização em substituição ao óleo de pescado marinho / Broodstock nutrition is one of the main aspects related with the quality of eggs and larvae produced. Lipids and its fatty acid composition are considered important on gonadal development, gonadotropic and steroid hormones, as well as influencing the formation of biological structures including cell membranes. In fish linoleic and linolenic are the essential fatty acids, which mabe converted into polyunsaturated fatty acids, like ARA, EPA and DHA, respectively. The marine fish oil are good sources of polyunsaturated fatty acids, however, vegetable oils are more communly used in fish diets. Thus, the aim of this study was to evaluate the ovarian and reproductive development of silver catfish (Rhamdia quelen) fed with lipid sources (soybean oil, marine fish oil, refined palm oil and a mixture). The lipid sources did not influence ovarian development, levels of estradiol, 17α-hidroxyprogesterona, and gonadosomatic index. However, the fatty acid changed fatty acid profile found in the liver, gonads and oocytes. Additionally, palm oil give rise to better fertilization rates and are recommended, suggesting that it may be used for fish oil replacement / CNPq: 142751/2011-1 / FAPESP: 2012/23089-4

Made available in DSpace on 2015-07-13T12:10:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-07-28. Added 1 bitstream(s) on 2015-07-13T12:25:39Z : No. of bitstreams: 1 000830996_20160728.pdf: 226829 bytes, checksum: 06b081184f452789c9c28be2682662c2 (MD5) Bitstreams deleted on 2016-07-29T12:53:56Z: 000830996_20160728.pdf,. Added 1 bitstream(s) on 2016-07-29T12:54:49Z : No. of bitstreams: 1 000830996.pdf: 1823064 bytes, checksum: bba12a5871b6e1a546ac402a5fb15b80 (MD5) / Objetivou-se analisar as táticas reprodutivas do curimatídeo nativo Cyphocharax modestus, em quatro pontos distintos (Alto, Médio, Baixo e Lago) distribuídos ao longo do rio Taquari e área de influência do reservatório de Jurumirim, Alto Rio Paranapanema, SP. Foram analisados um total de 1108 (401 fêmeas, 392 machos e 296 exemplares cujo o sexo não pode ser definido macroscopicamente). O material biológico foi obtido através de coletas mensais realizadas de setembro/2012 a agosto/2013, com a utilização de redes de espera. Cada exemplar teve o comprimento padrão medido (cm), pesado (g), dissecado para identificação macroscópica do sexo e a gônada retirada. Em seguida, as gônadas foram avaliadas quanto ao grau de maturação. A escala macroscópica para maturação gonadal foi verificada a por meio de análises histológicas, que também foram avaliadas quanto ao tipo de desova. Não foi verificado dimorfismo entre os sexos e sua proporção não apresentou desvio significativo de 1:1. O comprimento padrão em que 50% das fêmeas entram em processo de maturação gonadal (CP50%) foi estimado em 7,1 cm, sendo uma espécie de desova parcelada. Os valores calculados para RGS foram superiores para fêmeas em relação aos machos. Os valores de RGS das fêmeas foi significativamente superior nos pontos situados à montante em relação aos pontos da jusante, que não diferiram entre si. Para machos foi encontrado padrão semelhante ao das fêmeas, com valores decrescentes no sentido à jusante. A variação sazonal dos valores de RGS mostra que a atividade reprodutiva concentra-se na primavera e verão, com as fêmeas apresentando valores mais altos na primavera e verão, enquanto para machos os valores médios mais altos foram registrados a primavera, significativamente superiores aos das outras estações, que não diferiram significativamente entre si. Isto é corroborado pela variação da frequência de fêmeas maduras, que foi ... / The aim of this study was to analyze the reproductive tactics of the Cyphocharax modestus, a native fish of the family Curimatidae, at four different points distributed along the Taquari River and catchment area of the reservoir Jurumirim, Alto Rio Paranapanema, SP. The biological material was obtained through monthly collections made between September/2012 to August/2013 using of gillnets. Each specimen was measured for standard length (cm), was weighed (g) and dissected for macroscopic identification of sex. The gonads were weighed and macroscopically evaluated to their degree of maturation. The macroscopic gonad maturation was verified by histological analyzes, which were also assessed for spawning type and other details of reproductive biology. There was no sexual dimorphism and sex ratio showed no significant deviation from a 1:1 ratio. The CP50% of females of C. modestus was estimated at 7.1 cm, and histological evidence indicated to be a multiple spawner. The calculated values for RGS were higher for females and males average RGS of females was significantly higher in points located upstream relative to downstream points, which did not differ. For both males and females, a pattern of decreasing RGS values towards downstream was found, showing that the region of the upper Rio Taquari is a spawning area of this species. Seasonal variation of RGS shows that reproductive activity is concentrated in spring and summer, with females showing higher values in spring and summer, while for males the highest values were recorded in spring, significantly higher than the other stations, which do not differ significantly each other. This is corroborated by the variation in the frequency of mature females, which was higher in the months of September and October and males in the months of September and December. The information presented in this work allows us to conclude that this species has a relatively long reproductive period, during periods ...

Orientador: Irani Quagio-Grassiotto / Banca: Luís Fernando Fávero / Banca: Nelsy Fenerich Verani / Resumo: Nas fêmeas dos Teleostei a produção ilimitada de oócitos deve-se à constante proliferação das oogônias situadas no epitélio germinativo das lamelas ovígeras. Ao entrarem em meiose dão origem aos oócitos que são envoltos por uma camada de células foliculares, formando os folículos. No interior dos folículos, os oócitos passam por diferentes estágios de desenvolvimento (crescimento primário e secundário/vitelogênese, e maturação) ao final dos quais estão prontos para a desova. Os folículos pós-ovulatórios regridem e os óocitos que não tiveram sucesso na ovulação entram em atresia. A compreensão de como ocorre a foliculogênese nos Teleostei é recente e as descrições existentes referem-se aos grupos mais derivados. Por outro lado, os diferentes estágios de desenvolvimento dos oócitos, numa nova visão, vêm sendo utilizados na descrição de diferentes classes reprodutivas, ao longo do processo de maturação gonadal que ocorre a cada ano. Para testar a aplicabilidade desses novos conceitos aos Teleostei mais basais, analisou-se a foliculogênese e procedeu-se a caracterização celular das classes reprodutivas em Pimelodus maculatus, através de parâmetros histológicos, ultraestruturais e imunocitoquímico. Em P. maculatus a proliferação mitótica das oogônias, ocorre sempre acima da membrana basal, dá origem a conjuntos de células que são gradual e individualmente envoltos pelas células epiteliais, formando um tipo de cisto. As oogônias no interior dos cistos, ou oogônias secundárias entram em meiose ou dividem novamente 1, 2, 3 ou mais vezes por mitose e entram em meiose dando origem aos ovócitos. O conjunto de células, oócitos envoltos pelas células originárias do epitélio, forma uma espécie de sáculo, que se projeta para o estroma, mas permanece conectado ao próprio epitélio, compartilhando a mesma... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The unlimited production of oocytes in Teleostei females is due to the constant proliferation of the oogonia located in the germinal epithelium of ovigerous lamellae. Upon entering meiosis, oogonia give origin to the oocytes, which are surrounded by a layer of follicular cells and thus form the follicles. Within the follicles, oocytes undergo different developmental stages (primary and secondary growth/vitellogenesis, and maturation) followed by spawning. Post-ovulatory follicles regress and the oocytes that failed to ovulate enter atresia. The understanding of how folliculogenesis occurs in Teleostei has been recently achieved, and the descriptions available to date refer to the most derived groups. On the other hand, oocyte developmental stages have been used, under this new view, to describe the different reproductive classes seen along the gonadal maturation process that takes place every year. In order to test the applicability of these new concepts to the most basal Teleostei, this study aimed at analyzing folliculogenesis, and characterizing the cells found in these reproductive classes in Pimelodus maculatus, by using histological, ultrastructural and immunocitochemical parameters. In P. Maculatus, oogonia mitotic proliferation always occurs above the basement membrane, giving rise to cell sets which are gradually and individually surrounded by epithelial cells forming a sort of cyst. The oogonia located within the cysts, or secondary oogonia, either enter meiosis or divide again 1, 2, 3 or more times through mitosis, giving origin to oocyte. The cell set, oocytes surrounded by the cells originated from the epithelium, forms a sac-like structure that projects into the stroma, but remains connected to the epithelium sharing the same basement membrane. The early meiotic cells, which are small, have a basophilic nucleus, and a clear and scarce cytoplasm... (Complete abstract click electronic access below) / Mestre

Made available in DSpace on 2014-06-11T19:22:57Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-02-05Bitstream added on 2014-06-13T19:08:35Z : No. of bitstreams: 1 costa_rs_me_sjrp.pdf: 2335330 bytes, checksum: a362b3c9ff0199411e65f245cbed8903 (MD5) / 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... / 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)

Orientador: Igor Paiva Ramos / Orientador: Edmir Daniel Carvalho (In memorian) / Coorientador: Gianmarco Silva David / Coorientador: Fausto Viterbo / Banca: Rosicleire Veríssimo / Banca: Elizabeth Romagosa / Resumo: Objetivou-se analisar as táticas reprodutivas do curimatídeo nativo Cyphocharax modestus, em quatro pontos distintos (Alto, Médio, Baixo e Lago) distribuídos ao longo do rio Taquari e área de influência do reservatório de Jurumirim, Alto Rio Paranapanema, SP. Foram analisados um total de 1108 (401 fêmeas, 392 machos e 296 exemplares cujo o sexo não pode ser definido macroscopicamente). O material biológico foi obtido através de coletas mensais realizadas de setembro/2012 a agosto/2013, com a utilização de redes de espera. Cada exemplar teve o comprimento padrão medido (cm), pesado (g), dissecado para identificação macroscópica do sexo e a gônada retirada. Em seguida, as gônadas foram avaliadas quanto ao grau de maturação. A escala macroscópica para maturação gonadal foi verificada a por meio de análises histológicas, que também foram avaliadas quanto ao tipo de desova. Não foi verificado dimorfismo entre os sexos e sua proporção não apresentou desvio significativo de 1:1. O comprimento padrão em que 50% das fêmeas entram em processo de maturação gonadal (CP50%) foi estimado em 7,1 cm, sendo uma espécie de desova parcelada. Os valores calculados para RGS foram superiores para fêmeas em relação aos machos. Os valores de RGS das fêmeas foi significativamente superior nos pontos situados à montante em relação aos pontos da jusante, que não diferiram entre si. Para machos foi encontrado padrão semelhante ao das fêmeas, com valores decrescentes no sentido à jusante. A variação sazonal dos valores de RGS mostra que a atividade reprodutiva concentra-se na primavera e verão, com as fêmeas apresentando valores mais altos na primavera e verão, enquanto para machos os valores médios mais altos foram registrados a primavera, significativamente superiores aos das outras estações, que não diferiram significativamente entre si. Isto é corroborado pela variação da frequência de fêmeas maduras, que foi ... / Abstract: The aim of this study was to analyze the reproductive tactics of the Cyphocharax modestus, a native fish of the family Curimatidae, at four different points distributed along the Taquari River and catchment area of the reservoir Jurumirim, Alto Rio Paranapanema, SP. The biological material was obtained through monthly collections made between September/2012 to August/2013 using of gillnets. Each specimen was measured for standard length (cm), was weighed (g) and dissected for macroscopic identification of sex. The gonads were weighed and macroscopically evaluated to their degree of maturation. The macroscopic gonad maturation was verified by histological analyzes, which were also assessed for spawning type and other details of reproductive biology. There was no sexual dimorphism and sex ratio showed no significant deviation from a 1:1 ratio. The CP50% of females of C. modestus was estimated at 7.1 cm, and histological evidence indicated to be a multiple spawner. The calculated values for RGS were higher for females and males average RGS of females was significantly higher in points located upstream relative to downstream points, which did not differ. For both males and females, a pattern of decreasing RGS values towards downstream was found, showing that the region of the upper Rio Taquari is a spawning area of this species. Seasonal variation of RGS shows that reproductive activity is concentrated in spring and summer, with females showing higher values in spring and summer, while for males the highest values were recorded in spring, significantly higher than the other stations, which do not differ significantly each other. This is corroborated by the variation in the frequency of mature females, which was higher in the months of September and October and males in the months of September and December. The information presented in this work allows us to conclude that this species has a relatively long reproductive period, during periods ... / Mestre