Defects in meiotic prophase I events, resulting in aneuploidy, are a leading cause of birth defects in humans; however, these are difficult to study in mammalian systems due to their occurrence very early in development. The nematode, Caenorhabditis elegans, is an excellent model for prophase I studies as its gonad is temporally and spatially organized around these meiotic events. Homolog pairing, synapsis, meiotic recombination and crossover formation are essential to the proper segregation of chromosomes into the respective gametes, either the egg or sperm. Disturbances in these events leads to missegregation of chromosomes in the gametes in the meiotic divisions. Synapsis is especially critical in meiosis as it precedes and is required for meiotic recombination in C. elegans. The formation of the synaptonemal complex (SC) is fundamental to chromosomal synapsis, yet the molecular mechanisms of synaptonemal complex morphogenesis are largely unknown. The investigations described in this thesis were undertaken to better understand the molecular contributions to synaptonemal complex morphogenesis. Chapter One reviews knowledge of morphogenesis and its relationship to the events of meiotic prophase I. Recent studies in our laboratory have implicated AKIRIN, a nuclear protein with multiple biological functions, as having a role in synaptonemal complex disassembly, specifically preventing the aggregation of synaptonemal proteins (Clemons et al., 2013). As a result of our efforts to discern the mechanism by which AKIRIN regulates disassembly, we found that the highly conserved CSN/COP9 signalosome has a role in SC assembly, leading to defects in prophase I events and in MAPK signaling , leading to the arrest of nuclei in the later stages of meiosis. While the CSN/COP9 signalosome has been implicated in general fertility in C. elegans (Pintard et al., 2003), no role had been defined in earlier meiotic stages until this study. Chapter Two describes an RNAi enhancer/suppressor screen undertaken in the akir-1 mutant background. Several RNAi clones were selected for future study based on a reduction in brood size; one of which, csn-5/, is the focus of the analysis presented in Chapter 3. Chapter Three describes the phenotypic characterization of two CSN/COP9 signalosome subunits, csn-2 and csn-5. Alleles of both genes display synaptonemal complex protein aggregation and defects in mitotic cell proliferation, homologous chromosome pairing, meiotic recombination and crossover formation, leading to an increase in apoptosis. Oocyte maturation is also disrupted by a lack of MAPK signaling, resulting in a lack of viable oocytes, which renders the csnmutant homozygotes sterile. These findings support a model suggesting the CSN/COP9 signalosome has an essential role in regulating meiotic prophase I events and oocyte maturation. Chapter 4 describes the methodology used in this study. Chapter 5 provides a summary of the thesis findings and examines the future directions to extend this work.

Ce travail a consisté en l'étude de protéines de spermatozoïdes de différentes, avec l'objectif de contrôler leur pouvoir fécondant. Dans un premier temps une protéine antioxydante du tractus génital mâle, et acquise au cours de la maturation épididymaire, la glutathion peroxydase 5 (GPX5), a été étudiée dans deux espèces d'intérêt agronomique : l'étalon et le taureau. Les semences de ces animaux sont fréquemment conservées pour des inséminations artificielles. Or lors de la conservation, les spermatozoïdes subissent entre autres un stress oxydant. L'ajout de cette protéine antioxydante dans le milieu de conservation pourrait limiter les dommages subis par les spermatozoïdes. Les séquences spécifiques de cette protéine dans chaque espèce ont été obtenues. Les ARNm ont ensuite été localisés dans les canaux efférents et la tête de l'épididyme équine, ainsi que dans la tête et le corps de l'epididyme bovin. Par ailleurs la protéine bovine a été localisée dans la tête et le corps epididymaire. La seconde partie de ce travail a consisté a analyser les antigènes spermatiques spécifiques d'un rongeur fouisseur , le campagnol terrestre Arvicola terrestris Scherman dans le but de les utiliser pour une immunocontraception de cet animal nuisible. La détermination de protéines spermatiques suscepyibles d'être immunogènes a été entreprise.

Capelin (Mallotus villosus) is the key forage fish in the north Atlantic. A short-term anomalous event in Newfoundland waters in the early 1990’s caused many changes to their biology, including excursions into alternate (subtidal) spawning habitats. Subtidal spawning sites have drastically different environmental conditions than the beach sites that they have been using since at least the 1940’s. This thesis examines various aspects of the reproductive biology of capelin to understand the mechanisms underlying the use of two environmentally divergent spawning habitats. Local adaptation in early life history stages was examined by raising artificially fertilized capelin eggs across three temperatures that capelin are likely to encounter at both spawning habitats. At cool to medium temperatures, larvae experienced higher hatching success, were larger at hatching and had more nutritional reserves relative to warm temperature conditions. There was no evidence of local adaptation, providing the first support for a facultative spawning strategy. The influence of global warming temperatures may be buffered through the utilization of either spawning habitat provided it is within this thermal optimum. A comparative analysis of adult body shape and condition between the two habitats provided further evidence that spawning habitat use in a given year is facultative. Patterns in fecundity drastically changed for capelin since it was last examined prior to the 1990’s. In addition to lower average population fecundity, a wide range of fecundities was also observed across all length-classes. I show that the strong relationship between length and fecundity in capelin has broken down in recent years, making easily collected size measurements an inappropriate proxy for the reproductive potential of this fish. Within-female variation in offspring size and developmental duration was higher when compared to among-female variation. This supports diversified bet-hedging in capelin, a strategy that would allow capelin to spawn in thermally available habitats without experiencing reproductive failure in exceedingly warm or cold years. It is likely that high variation in traits allow capelin to utilize alternate spawning habitats, ensuring that at least some larvae survive.

Capelin (Mallotus villosus) is the key forage fish in the north Atlantic. A short-term anomalous event in Newfoundland waters in the early 1990’s caused many changes to their biology, including excursions into alternate (subtidal) spawning habitats. Subtidal spawning sites have drastically different environmental conditions than the beach sites that they have been using since at least the 1940’s. This thesis examines various aspects of the reproductive biology of capelin to understand the mechanisms underlying the use of two environmentally divergent spawning habitats. Local adaptation in early life history stages was examined by raising artificially fertilized capelin eggs across three temperatures that capelin are likely to encounter at both spawning habitats. At cool to medium temperatures, larvae experienced higher hatching success, were larger at hatching and had more nutritional reserves relative to warm temperature conditions. There was no evidence of local adaptation, providing the first support for a facultative spawning strategy. The influence of global warming temperatures may be buffered through the utilization of either spawning habitat provided it is within this thermal optimum. A comparative analysis of adult body shape and condition between the two habitats provided further evidence that spawning habitat use in a given year is facultative. Patterns in fecundity drastically changed for capelin since it was last examined prior to the 1990’s. In addition to lower average population fecundity, a wide range of fecundities was also observed across all length-classes. I show that the strong relationship between length and fecundity in capelin has broken down in recent years, making easily collected size measurements an inappropriate proxy for the reproductive potential of this fish. Within-female variation in offspring size and developmental duration was higher when compared to among-female variation. This supports diversified bet-hedging in capelin, a strategy that would allow capelin to spawn in thermally available habitats without experiencing reproductive failure in exceedingly warm or cold years. It is likely that high variation in traits allow capelin to utilize alternate spawning habitats, ensuring that at least some larvae survive.

The biology of four species of Choerodon (Labridae), the blue tuskfish C. cyanodus, the bluespotted tuskfish C. cauteroma, the baldchin groper C. rubescens and the blackspot tuskfish C. schoenleinii was studied in Shark Bay in Western Australia. These species are fished commercially and/or recreationally in this large subtropical marine embayment, which is a world heritage area. The biology of C. rubescens was also studied in the Abrolhos Islands, which are located ~ 300 km to the south of Shark Bay, where this labrid is an important commercial and recreational fish species. The broad aims of this project were to determine the following for the above four Choerodon species in Shark Bay. (1) Whether they are protogynous hermaphrodites, as is the case with many labrids. (2) The biological variables required for developing management plans for these species, such as the timing of spawning, the lengths and ages at both maturity and sex change, size and age compositions and growth parameters, and (3) the habitat types occupied during their life cycles and also of the purple tuskfish Choerodon cephalotes. Finally, comparisons are made between the age and size compositions, growth and reproductive biology of C. rubescens in Shark Bay and the Abrolhos Islands. Where relevant, the underlying hypotheses for the individual studies conducted during this PhD are included in the following chapters. A macroscopic and histological examination of the gonads of the full size range of C. cyanodus, C. cauteroma, C. rubescens and C. schoenleinii, together with an analysis of the length and age compositions of female, transitional (individuals changing sex) and male individuals, demonstrated that each of these species is a protogynous hermaphrodite, i.e. individuals change sex from female to male during their life cycle. The gonads of all small (< ca 100 mm) and young (< ca 1 year old) individuals of each species comprised solely ovarian tissue and thus the individuals of each species began life as a female. All individuals subsequently become sexually mature as females and then later in life some will change to males. Since this was found to be the only method of sex change in these species, they are termed monandric. Individuals that were changing sex contained “undelimited type 2” gonads sensu Sadovy and Shapiro (1987). These gonads contained both ovarian and testicular tissue that was intermixed and not separated by connective tissue. The males of each species possessed secondary testes, which retained structures of the ovary they had replaced, such as a membrane-lined ovarian lumen, lamellae and ovary wall. Furthermore, histological sections indicated that sperm were transported towards the outer walls of the testes, where the multiple sperm sinuses present in that region were presumably responsible for transporting sperm to the cloaca, rather than to a singular sperm duct as is the case with gonochoristic species. The typically large size and different colour of the males of C. rubescens, C. schoenleinii and C. cauteroma and the bias in the sex ratios of their adults towards females suggests that the males of each of these species are either haremic, i.e. permanently territorial, or form leks, i.e. are temporarily territorial during their spawning seasons. In these three species, the presence of ripe testes that are far smaller than ripe ovaries and the release by females of eggs in batches are consistent with a single male spawning with an individual female, as commonly occurs in haremic/lekking species. In contrast to the above species, C. cyanodus was not sexually dichromatic, the sex ratio was not biased towards either sex and the weight of ripe testes remained relatively constant as body weight increased. The latter implies that the relative investment of energy by males into testicular development during the spawning season declines with increasing fish size. Thus, the males of C. cyanodus may be opportunistic spawners when small, possibly spawning in groups, and may tend towards a haremic or lek mode of life when larger. The respective lengths and ages at which 50% of the females of C. cyanodus C. cauteroma and C. schoenleinii attained sexual maturity (L50m, A50m) in Shark Bay were ca 129, 196 and 253 mm and 2.3, 2.0 and 3.5 years of age. The corresponding L50m and A50m for C. rubescens in Shark Bay and the Abrolhos Islands were ca 274 and 279 mm, respectively, and 2.7 and 4.1 years of age, respectively. The respective lengths and ages at which 50% of the females of C. cyanodus, C. cauteroma and C. schoenleinii changed to males (L50c, A50c) in Shark Bay were 221, 310 and 556 mm and 4.1, 6.4 and 10.4 years of age. The length at which C. rubescens changed sex (L50c) was significantly greater in Shark Bay (545 mm) than in the Abrolhos Islands (479 mm), whereas the reverse pertained with respect to the age at sex change (A50c), i.e. 10.5 vs 11.9 years of age. Since some females were found in the oldest age classes of each species in Shark Bay and in the population of C. rubescens in the Abrolhos Islands, some of the females of each species do not apparently change sex. The trends exhibited by the gonadosomatic indices of females and males and the stages of ovarian development in sequential months demonstrated that the spawning periods of each species varied. Thus, C. rubescens (in both Shark Bay and the Abrolhos Islands) and C. cauteroma spawn predominantly in spring, whereas spawning occurs in late spring/early summer in C. schoenleinii and in summer in C. cyanodus. As C. schoenleinii, C. cyanodus and C. cauteroma occur predominantly within the inner gulfs of Shark Bay, the offset in the timing of their spawning periods would be likely to reduce any potential for competition between the larvae of those three species for resources. The trends exhibited by the mean monthly marginal increments in sectioned otoliths with differing numbers of opaque zones demonstrated that, in each species, those opaque zones were laid down annually. Thus, the numbers of opaque zones in the sectioned otoliths of individuals of each species could be used, in conjunction with the birth date and time of year when those zones are delineated, to determine their approximate ages at capture. The maximum ages recorded for the four Choerodon species in Shark Bay ranged only from 12 to 16 years. However, in that environment, the maximum lengths of C. rubescens (649 mm) and C. schoenleinii (805 mm) were far greater than those of C. cauteroma (424 mm) and C. cyanodus (382 mm). In contrast to the situation with C. rubescens in Shark Bay, this species reached a substantially older maximum age (22 years), but slightly shorter length (629 mm), and grew at a slower rate in the Abrolhos Islands, possibly reflecting the influence of greater productivity in Shark Bay and/or greater densities of this species in the Abrolhos Islands. Although a few C. rubescens and C. schoenleinii reach large sizes in Shark Bay, most of the individuals of these species were less than 400 mm, their minimum legal length (MLL) for capture. This raises the possibility that these two sought after species, i.e. the seventh and ninth most abundant species in the recreational fishery in Shark Bay, are subjected to substantial fishing pressure. Sampling for C. cyanodus was considered representative of the sites that this species occupies in Shark Bay and the sampling methods would have been likely to have captured the full size range of this tuskfish. Thus, the failure to catch any C. cyanodus greater than 400 mm indicates that, in Shark Bay, this species does not grow to the far greater lengths of about 600 mm reported for this species as a maximum by Allen (1999). Furthermore, the 400 mm MLL for this species in Western Australia precludes the retention by fishers of this species in this environment. Choerodon cauteroma was caught at lengths up to 424 mm, which is greater than the maximum of 360 mm reported for this species (Allen, 1999). Although there is no MLL for C. cauteroma, recreational fishers are restricted to a bag limit of four fish per person per day, as is the case with all other tuskfish species. Since fishers target large fish preferentially and the largest size classes of each of the species of tuskfish are dominated by males, heavy fishing pressure has the potential to remove a large proportion of the males of the Choerodon species that are fished in Shark Bay, i.e. C. rubescens, C. schoenleinii and C. cauteroma, and also of C. rubescens in the Abrolhos Islands. Since the ratio of females to males in catches of C. rubescens taken by the commercial fishery in the Abrolhos Islands are ca 1:1 and yet the typical adult sex ratio is heavily biased towards females (ca 14:1), that fishery is removing a substantial proportion of the males from the population. Protogynous hermaphroditic species are apparently able to respond to such pressure on the males by initiating a change in sex by the larger females. However, there is evidence from studies of other protogynous species that heavy size-selective fishing can lead to a reduction in the size and age at which a species changes sex and ultimately to a collapse in the stock. The results of visual surveys, when taken in conjunction with the locations of the catches of each of the five Choerodon species, demonstrated that C. rubescens lives on reefs in “oceanic” waters along the western boundary of Shark Bay, whereas C. schoenleinii, C. cyanodus, C. cauteroma and C. cephalotes are found predominantly in the two inner gulfs of this large embayment. Choerodon cephalotes lives almost exclusively in seagrass beds, while C. schoenleinii and C. cyanodus occupy predominantly inner gulf reefs and rocky shorelines and C. cauteroma occurs in all of those three habitats. Choerodon cauteroma was the only species that underwent an obvious size-related shift during its life cycle, moving from seagrass to hard substrates, such as inner gulf reefs and rocky shorelines, as it reached adulthood. The biological and habitat data produced during this thesis will provide fisheries and environmental managers with the types of information that will enable them to develop management plans for conserving tuskfish species and their habitats in Shark Bay. The biological data for C. rubescens in the Abrolhos Islands will be able likewise to be used to develop plans for conserving the stock of this species in waters in which it is heavily fished.

Orientador: Marcos César de Oliveira Santos / Banca: Daniel Danilewicz Schiavon / Banca: Carmen Silvia Fontanetti Christofoletti / Resumo: A biologia reprodutiva de toninhas, Pontoporia blainvillei, capturadas acidentalmente em redes de pesca entre abril de 2005 e agosto de 2007 do sul do estado de São Paulo (24º24'S, 46°57'W) ao norte do Paraná (25º22'S, 48º09'W) foi estudada. Os testículos de 57 machos e os ovários de 35 fêmeas foram analisados macro e microscopicamente para determinação da maturidade sexual. As presenças de leite nas glândulas mamárias e de feto no útero foram avaliadas para determinação de lactação e de prenhez das fêmeas, respectivamente. A proporção apresentada entre machos e fêmeas capturados acidentalmente foi de 1,6:1. As idades de 86 indivíduos foram estimadas a partir da contagem do número de grupos de linhas de crescimento presentes nas camadas de dentina e de cemento dos dentes. As idades variaram de zero a 18 anos para machos e de zero a 12 anos para fêmeas. A mediana das idades foi de um ano e 75 indivíduos (87,2%) tinham até três anos de idade. A análise histológica revelou que 21 dos 57 machos analisados (36,8%) estavam sexualmente maduros. Os testículos apresentaram simetria lateral e baixo peso testicular relativo em relação ao peso corporal, sendo em média de 0,031% em machos maduros sexualmente. O peso testicular combinado (soma dos pesos de ambos os testículos), a largura testicular média, o comprimento testicular médio e o índice de maturidade testicular (razão entre o peso e o comprimento dos testículos) se demonstraram como potenciais ferramentas macroscópicas para auxiliar na identificação de indivíduos maduros, mas a análise histológica ainda é necessária para confirmação dos estágios de maturidade em machos / Abstract: The reproductive biology of franciscana dolphins, Pontoporia blainvillei, incidentally caught by gillnets between 2005 and 2007 from southern São Paulo (24°24'S, 46°57'W) to northern Paraná (25º22'S, 48°09'W) States was studied. The testes of 57 males and the ovaries of 35 females were macroscopically and microscopically analyzed to determine the sexual maturity. The presence of milk in the mammary glands and of fetus in the uterus was evaluated to determine lactating and pregnant females, respectively. The ratio between males and females incidentally caught was 1.6:1. The age (n=86) was estimated through growth layer groups in dentine and cementum using longitudinal sections of teeth. The ages ranged from zero to 18 years for males and from zero to 12 years for females. The median of age was one year and 75 individuals (87.2%) were three years old or less when captured. Histological analysis revealed that 21 of the 57 males analyzed (36.8%) were sexually mature. The testes showed lateral symmetry and low testicular weight relative to body weight, with an average of 0.031% in sexually mature males. The combined testicular weight (sum of weights of both testes), the average testicular width, the average testicular length and testicular maturity index (ratio of testicular weight per testicular length) were considered as potential macroscopic tools to classify mature individuals, but histological confirmation is still required to confirm the sexual maturity condition / Mestre

Orientador: Rogério Caetano da Costa / Banca: Roberto Munehisa Shimizu / Banca: Antônio Leão Castilho / Resumo: o presente estudo teve como objetivo averiguar a abundância do camarão sete-barbas, Xiphopenaeus kroyeri, e a influência de fatores ambientais como temperatura e salinidade da água de fundo e textura e porcentagem de matéria orgânica do sedimento, na distribuição espaçotemporal da espécie ao longo do complexo Baía/Estuário de Santos e São Vicente. As amostragens foram realizadas mensalmente de junho de 2008 a maio de 2009 em quatro pontos no Estuário de São Vicente e quatro na Baía de Santos em profundidades que variaram de 3 a 15 metros, aproximadamente. As amostras de água de fundo foram obtidas para se determinar a temperatura e a salinidade e as amostras de sedimento foram utilizadas para análise da fração granulométrica e da porcentagem de matéria orgânica de cada ponto. Os valores da salinidade média no estuário variaram de 24,5 Uulho) a 32,5 psu (outubro) e na baía, de 32,5 Uulho) a 39,5 psu (setembro). Foi observada uma menor amplitude de variação nos valores de temperatura no estuário, entre 21,7°C Uulho) e 29,5°C (março), quando comparada com a baía, entre 18,2 (dezembro) e 28,O°C (fevereiro). Em todos os pontos da baía, a fração granulométrica que prevaleceu foi de areia muito fina e no estuário, houve uma variação de silte e argila a areia fina. Com exceção de um dos pontos do estuário, a porcentagem de matéria orgânica foi sempre menor que 3. Dos 60.274 indivíduos coletados, nenhum foi capturado no estuário e este fato pode estar relacionado à baixa salinidade observada no local. Desse modo, a espécie deve ser incluída no ciclo de vida tipo 111, ou seja, o ciclo de vida completa-se em regiões costeiras marinhas. Já a temperatura... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The aim of the present study was to analyze the abundance of the seabob shrimp, Xiphopenaeus kroyeri, and the influence of environmental factors as temperature and salinity (bottom water), organic matter content and grain size of sediments, in the spatial-temporal distribution of the species along the complex Bay/Estuary of Santos and São Vicente. Samples were taken monthly between June 2008 and May 2009 in four sites in São Vicente Estuary and four sites in Santos Bay in depths from 3 to 15m. The bottom water samples were obtained to determine the temperature and salinity and the sediment samples to analyze the grain size and organic matter content of each site. The mean values of salinity varied in the estuary from 25.5 (July) to 32.5 psu (October) and, in the bay, from 32.5 (July) to 39.5 psu (September). It was observed lower amplitude of variation in temperature values in the estuary, between 21.7 (July) and 29.5°C (March) when compared with the bay, between 18.2 (December) and 28.0°C (February). In ali sites in the bay, it was observed predominance of very fine sand and, in the estuary, there was a variation from silt and clay and fine sand. Excepting one site in the estuary, the percentage of organic matter content was always lower than 3. In a total of 60,274 individuais obtained, none of them was caught in the estuary and this fact can be related with low values of salinity observed in the local. Thus the species has to be included in the life cycle type 3, which is completed from the inshore to offshore areas. High values of temperature were determinants when associated with adult males and matured females. The species remained in the region ali year round and low temperatures have forced a population migration to lower depths... (Complete abstract click electronic access below) / Mestre

Made available in DSpace on 2014-06-11T19:30:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-02-19Bitstream added on 2014-06-13T21:00:32Z : No. of bitstreams: 1 heckler_gs_me_botib.pdf: 885060 bytes, checksum: 0aad2d1acde396306968425b40eb5ccd (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / o presente estudo teve como objetivo averiguar a abundância do camarão sete-barbas, Xiphopenaeus kroyeri, e a influência de fatores ambientais como temperatura e salinidade da água de fundo e textura e porcentagem de matéria orgânica do sedimento, na distribuição espaçotemporal da espécie ao longo do complexo Baía/Estuário de Santos e São Vicente. As amostragens foram realizadas mensalmente de junho de 2008 a maio de 2009 em quatro pontos no Estuário de São Vicente e quatro na Baía de Santos em profundidades que variaram de 3 a 15 metros, aproximadamente. As amostras de água de fundo foram obtidas para se determinar a temperatura e a salinidade e as amostras de sedimento foram utilizadas para análise da fração granulométrica e da porcentagem de matéria orgânica de cada ponto. Os valores da salinidade média no estuário variaram de 24,5 Uulho) a 32,5 psu (outubro) e na baía, de 32,5 Uulho) a 39,5 psu (setembro). Foi observada uma menor amplitude de variação nos valores de temperatura no estuário, entre 21,7°C Uulho) e 29,5°C (março), quando comparada com a baía, entre 18,2 (dezembro) e 28,O°C (fevereiro). Em todos os pontos da baía, a fração granulométrica que prevaleceu foi de areia muito fina e no estuário, houve uma variação de silte e argila a areia fina. Com exceção de um dos pontos do estuário, a porcentagem de matéria orgânica foi sempre menor que 3. Dos 60.274 indivíduos coletados, nenhum foi capturado no estuário e este fato pode estar relacionado à baixa salinidade observada no local. Desse modo, a espécie deve ser incluída no ciclo de vida tipo 111, ou seja, o ciclo de vida completa-se em regiões costeiras marinhas. Já a temperatura... / The aim of the present study was to analyze the abundance of the seabob shrimp, Xiphopenaeus kroyeri, and the influence of environmental factors as temperature and salinity (bottom water), organic matter content and grain size of sediments, in the spatial-temporal distribution of the species along the complex Bay/Estuary of Santos and São Vicente. Samples were taken monthly between June 2008 and May 2009 in four sites in São Vicente Estuary and four sites in Santos Bay in depths from 3 to 15m. The bottom water samples were obtained to determine the temperature and salinity and the sediment samples to analyze the grain size and organic matter content of each site. The mean values of salinity varied in the estuary from 25.5 (July) to 32.5 psu (October) and, in the bay, from 32.5 (July) to 39.5 psu (September). It was observed lower amplitude of variation in temperature values in the estuary, between 21.7 (July) and 29.5°C (March) when compared with the bay, between 18.2 (December) and 28.0°C (February). In ali sites in the bay, it was observed predominance of very fine sand and, in the estuary, there was a variation from silt and clay and fine sand. Excepting one site in the estuary, the percentage of organic matter content was always lower than 3. In a total of 60,274 individuais obtained, none of them was caught in the estuary and this fact can be related with low values of salinity observed in the local. Thus the species has to be included in the life cycle type 3, which is completed from the inshore to offshore areas. High values of temperature were determinants when associated with adult males and matured females. The species remained in the region ali year round and low temperatures have forced a population migration to lower depths... (Complete abstract click electronic access below)

Made available in DSpace on 2014-06-11T19:30:15Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-08-12Bitstream added on 2014-06-13T21:00:38Z : No. of bitstreams: 1 silva_df_me_rcla.pdf: 1778952 bytes, checksum: a376ba77746867b99630c47a08cee512 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A biologia reprodutiva de toninhas, Pontoporia blainvillei, capturadas acidentalmente em redes de pesca entre abril de 2005 e agosto de 2007 do sul do estado de São Paulo (24º24’S, 46°57’W) ao norte do Paraná (25º22’S, 48º09’W) foi estudada. Os testículos de 57 machos e os ovários de 35 fêmeas foram analisados macro e microscopicamente para determinação da maturidade sexual. As presenças de leite nas glândulas mamárias e de feto no útero foram avaliadas para determinação de lactação e de prenhez das fêmeas, respectivamente. A proporção apresentada entre machos e fêmeas capturados acidentalmente foi de 1,6:1. As idades de 86 indivíduos foram estimadas a partir da contagem do número de grupos de linhas de crescimento presentes nas camadas de dentina e de cemento dos dentes. As idades variaram de zero a 18 anos para machos e de zero a 12 anos para fêmeas. A mediana das idades foi de um ano e 75 indivíduos (87,2%) tinham até três anos de idade. A análise histológica revelou que 21 dos 57 machos analisados (36,8%) estavam sexualmente maduros. Os testículos apresentaram simetria lateral e baixo peso testicular relativo em relação ao peso corporal, sendo em média de 0,031% em machos maduros sexualmente. O peso testicular combinado (soma dos pesos de ambos os testículos), a largura testicular média, o comprimento testicular médio e o índice de maturidade testicular (razão entre o peso e o comprimento dos testículos) se demonstraram como potenciais ferramentas macroscópicas para auxiliar na identificação de indivíduos maduros, mas a análise histológica ainda é necessária para confirmação dos estágios de maturidade em machos / The reproductive biology of franciscana dolphins, Pontoporia blainvillei, incidentally caught by gillnets between 2005 and 2007 from southern São Paulo (24°24’S, 46°57’W) to northern Paraná (25º22’S, 48°09’W) States was studied. The testes of 57 males and the ovaries of 35 females were macroscopically and microscopically analyzed to determine the sexual maturity. The presence of milk in the mammary glands and of fetus in the uterus was evaluated to determine lactating and pregnant females, respectively. The ratio between males and females incidentally caught was 1.6:1. The age (n=86) was estimated through growth layer groups in dentine and cementum using longitudinal sections of teeth. The ages ranged from zero to 18 years for males and from zero to 12 years for females. The median of age was one year and 75 individuals (87.2%) were three years old or less when captured. Histological analysis revealed that 21 of the 57 males analyzed (36.8%) were sexually mature. The testes showed lateral symmetry and low testicular weight relative to body weight, with an average of 0.031% in sexually mature males. The combined testicular weight (sum of weights of both testes), the average testicular width, the average testicular length and testicular maturity index (ratio of testicular weight per testicular length) were considered as potential macroscopic tools to classify mature individuals, but histological confirmation is still required to confirm the sexual maturity condition

Orientador: Antonia Cecilia Zacagnini Amaral / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-17T23:13:54Z (GMT). No. of bitstreams: 1 Corte_GuilhermeNascimento_M.pdf: 5320996 bytes, checksum: 8ad80f2977ae7beb8dadab02a6469226 (MD5) Previous issue date: 2011 / Resumo: Não informado / Abstract: Not informed / Mestrado / Ecologia / Mestre em Ecologia