The research presented in this thesis was undertaken in order to develop an understanding of the biology of Perna canaliculus sufficient to allow for commercial hatchery based production of Greenshell™ mussel spat. Hatchery production is an alternative to unreliable and inconsistent wild spat collection. In a Perna canaliculus population followed for one year spawning occurred in early spring and late summer. Three quantitative histological measures of gonad maturity utilising image analysis technology and a qualitative classification system were compared. Measuring the relative surface area comprised of gametes on histological sections was found to be the most reliable method. A practical gonad visual index to determine the reproductive condition of adults for the selection of broodstock was developed and found to be highly effective as a means of predicting induced spawning success. Serotonin was not effective for inducing spawning of Perna canaliculus. Temperature shock and the use of stripped gametes was however found to be a reliable spawning induction method. Relative gamete concentration, gamete age, temperature, sperm half life and gamete contact times were all found to have effects on fertilisation success for Perna canaliculus. Sperm concentration and the conditions of sperm aging were particularly important. Fertilisation kinetics of Perna canaliculus gametes modelled using the Vogel-Czihak-Chang-Wolf method suggested that 5% of sperm-egg contacts lead to successful fertilisation. Broodstock management protocols that could be used to condition the adult of Perna canaliculus were investigated in order to enhance and prolong the natural reproductive season. Research suggested that for successful broodstock conditioning animals should already have begun gametogenesis at the time conditioning is commenced. Successful conditioning of Perna canaliculus was achieved at temperatures between l0 and 16°C over a period of about 50 days. A diet ration above 2-3% of the dry meat mass per day is suggested. A trial examining non-algal diet supplements suggest a mixture of yeast and lipid emulsion may have some potential value. Photoperiod manipulation did not effect the reproductive condition of Perna canaliculus. The yield of veliger larvae was significantly enhanced if embryo culture water was treated with 1.0 mg/l EDTA. Veliger yield was not significantly affected at densities below 50 embryos/ml. Perna canaliculus larvae grew most rapidly and survived well at the salinity of 35 ppt. Larvae grew most rapidly when cultured at low densities. Experiments suggest that early larvae can be cultured at 5-10/ml, however late stage larvae grew most rapidly when cultured at l/ml. Perna canaliculus larvae displayed best growth and good survival if fed a mixed flagellate-diatom diet comprising Isochrysis galbana (T-Iso) and Chaetoceros calcitrans. The optimal diet ration, as a function of larval size, increased from about 20 cells/μl Isochrysis galbana (T-Iso) to around 150 cells/μl through the larval development period. Thyroxine between the concentrations of l0-5 and l0-8 M did not have an observable effect on larval developmental rate or eye spot development. Down welling settlement systems were found to be generally successful for Perna canaliculus lanrae. L-DOPA was also demonstrated to enhance the settlement and metamorphosis of Perna canaliculus pediveligers.

This thesis presents a descriptive and a functional analysis of the ecology of an island host-parasite system consisting of the Polynesian rat, Rattus exulans (Peale) and its gut helminths. The results, which include an historical perspective, are presented in the form of 7 papers or sections. Each of these examines a particular aspect of this host-parasite relationship. A review of the origin and an update of the theorised dispersal of this rat from Southeast Asia to New Zealand is given in the first section of chapter one. Previous theories have derived the New Zealand populations from a line which passed through Micronesia. In accordance with new information from the Lapita cultural assemblage, this rat is now theorised to have accompanied these "Lapita" peoples through the Bismarck Archipelago and Solomon Islands, arriving in the Tonga- Samoa region about 3600-3000 Before Present (B.P.). From here, the Proto- Polynesians then dispersed further east, taking with them the commensal R. exulans, pig, dog, and chicken. This rat is thus thought to have arrived in New Zealand, the most southern and last-settled landmass in Polynesia, in the canoes of the Maori about 1000 years ago. Information on the ecto- and endoparasites of the Polynesian rat from throughout its geographical range is collated and presented in section two. This includes the results of the two surveys (one being part of this thesis) done on the parasites of this rat in New Zealand. All populations of R. exulans sampled in these two surveys came from offshore islands, to which this rat is almost totally confined, and where, on many, it is the only rodent species present. In contrast, most of the populations sampled beyond New Zealand are now sympatric with other rodent species. For the New Zealand populations only, it was also possible to identify those parasites only accidentally associated with this host; these are listed as "transients". In section three, an attempt is made to determine the probable biogeographical origins of parasites recorded from populations of this rat on "exulans only" offshore islands of New Zealand. Such a study was possible only because of the archaeologically documented commensal relationship between rat and Polynesian man. This information, detailed in section one, together with the parasitological data base assembled in section two, provided the material for this analysis. Several "heirloom" species are identified, theorised to have been inherited by this rat during speciation somewhere in Island Southeast Asia. Parasites acquired during dispersal are divided into "old" and "new souvenirs"; the former are thought to have been acquired from sympatric rodent species in Near Oceania sometime prior to 3000 B.P., and the latter from R. rattus, R. norvegicus or Mus musculus introduced in the last 200 years during European settlement in New Zealand. The conclusions further suggest that some at least of the "new souvenir" species have been acquired by R. exulans on "exulans only" offshore islands of New Zealand by cross-transfer from other rodent species which have temporarily gained access to these islands. This theory is examined in more detail in the fourth section, and reports of such accidental colonizations of offshore islands are presented as supporting evidence. In Chapter two, the influence of habitat on the population demography of the host is investigated. Nearly 1000 rats were trapped and necropsied over a 17 month period in three different habitats on Tiritiri Matangi, an "exulans only" island at the entrance to the Auckland harbour. Rank grassland which covers most of this island formed one habitat; a second consisted of forest remnants confined to gullies, and the third consisted of the small, inhabitated, lighthouse station and farmed area at one end of the island. Between-habitat differences were observed in diet, adult longevity, mean weight of immatures, the time of onset of sexual maturation, and annual reproductive output. These results suggested several modifications to existing models of this host's demography in New Zealand. Shelter in particular appears to play an important role in the demography of this species in temperate latitudes. The effects of parasitism on potential fitness parameters e.g. reproduction, and adult mortality/survival, are examined in chapter three. Based on the results obtained in chapter two, a number of hypotheses were developed, and the predictions arising from these were tested. Few significant results were obtained; these revealed habitat and some sexual interactions with the level of infection, at certain times of the year. However, no causal relationship could be established between these effects and host reproduction or mortality. It is concluded that the helminth parasites of this rat on this island have little or no effect on these host parameters, and support the suggestion that these species constitute a depauperate and well-adapted rodent parasite fauna. The last chapter presents the results of an analysis of the effects of habitat, season, host age, and sex on the distribution and abundance of the helminths of this rat on this island. Together, the graphs and the statistical analyses demonstrate that habitat has the most important influence, significantly affecting all 7 species; this effect is of greater magnitude than the other 3 variables on 5/7 of these species. Season and age also have important effects, while sex had no apparent influence. Explanations for the observed patterns are sought in known aspects of the biology of the host in the three habitats described in chapter two, and in the life cycles of the parasites. In total, this thesis provides a comprehensive account of the ecology of the Polynesian rat and its helminth parasites on Tiritiri Matangi Island. It also identifies gaps in the existing data base, formulates certain hypotheses, and makes a number of predictions all of which will hopefully stimulate further interest in this rat and its parasites.

Interactions among large brown macroalgae, sea urchins, and fishes were investigated in northeastern New Zealand during the period 1988 - 1993. The Cape Rodney to Okakari Point Marine Reserve was the site of many of these investigations. The patterns of abundance of large brown macroalgae and urchins down depth gradients over a wide geographic range were compared with those reported from earlier studies, and 3 major trends were identified. First, the fucoid alga Carpophyllum flexuosum now occurs at many sites which are exposed to wave action, in contrast to earlier studies. This alga occurred most abundantly on urchin-grazed coralline flat areas. Second, at four sites in the Marine Reserve, the densities of the echinometrid urchin Evechinus chloroticus decreased with increasing depth, rather than reaching maximal densities at mid-depths, as had previously been described. Finally, at sites of decreased exposure to wave action, the coralline flats habitat did not occur at all, and dense stands of. C. flexuosum occurred, in conjunction with the ubiquitous laminarian alga, Ecklonia radiata. Following the discovery of this new algal component to exposed rocky reefs, a more detailed study of its population characteristics was initiated. The population size structure of C. flexuosum on coralline flat areas was markedly different from that of the same species in sites sheltered from wave action. These differences occurred at both offshore islands and sites near Leigh, suggesting that it was a general pattern. C. flexuosum plants on coralline flats were smaller than those from sheltered sites, and had a greater number of smaller laminae, heavier stipes, and a greater degree of branching. There was some evidence of temporal change in the morphology of C. flexuosum from coralline flats. Comparisons between a site with C. flexuosum and a site with coralline flats suggested that the activity of fish was 75% lower in the vegetated than in the unvegetated site, and the feeding rate in the vegetated site was less than 50% that in the unvegetated site. I speculate that future effects on fish activity of the invasion of C. flexuosum into a habitat which previously lacked macroalgal vegetation may depend on changes in the morphology of plants. An investigation of many aspects of the biology of E. chloroticus in different habitats was undertaken. Analysis of the body dimensions of E. chloroticus suggested that this species was relatively tall compared to other echinometrids (average ratio of test height: test diameter = 0.54), Comparisons among habitats with differing amounts of vegetation revealed only small differences in the relationship between test diameter and test height. Small E. chloroticus (<40 mm test diameter) lived in crevices, while larger individuals grazed freely over the substratum. In vegetated habitats, the crevice-dwelling habit was maintained at test diameters about l0 mm greater than in unvegetated habitats. Very small (<20 mm test diameter) E. chloroticus frequently covered themselves with shell. Population size structures of E. chloroticus within the Cape Rodney to Okakari Point Marine Reserve were bimodal; other localities had unimodal populations. Modal sizes varied among localities, with smallest modes (50-60 mm TD) being found at Inner Hauraki Gulf sites, and largest modes at the offshore Mokohinau Islands (70-80 mm TD). Habitat did not predictably affect population size structure. A bimodal population structure was maintained at Waterfall Reef rock flats throughout the 5-year study period. Gonad size showed seasonal fluctuations at several sites, being greatest in summer. There were few consistent differences in gonad size between biological habitats. Gonad colour varied among sites and habitats, with orange gonads generally being more prevalent in vegetated habitats, and black gonads being represented more in unvegetated habitats. Smaller urchins had greater proportions of orange gonads, while larger urchins had greater proportions of brown and black gonads. Although highly variable among individual urchins, movement of E. chloroticus was greater at unvegetated sites (0.7 m per 5 days) than at vegetated sites (0.4 m per 5 days), in the Marine Reserve. Feeding of E. chloroticus was studied at a number of sites in the Marine Reserve. Urchins frequently consumed drift algae, particularly E. radiata. C. flexuosum was consumed at less than half the rate of other macroalgae in several laboratory feeding experiments, and was chosen least frequently in a field assay of feeding preferences among 8 species of macroalgae. Boosting densities of E. chloroticus in stands of E. radiata to 60 m-2 led to destructive grazing of plants over a 2 month period - at lower densities, the urchins dispersed. Densities of C. flexuosum were effectively unchanged when urchin densities were increased to these elevated levels. As a result of these observations I speculate that feeding preferences of E. chloroticus may have a role in allowing C. flexuosum to survive on coralline flats. In a laboratory experiment, urchins from a feeding aggregation did not graze algae at higher rates than individuals from outside aggregations. Diets of both E. radiata and C. flexuosum consistently produced similar gonad volumes in urchins held in the laboratory, although gonad volumes produced were low. A preliminary experiment suggested that C. flexuosum from exposed sites was consumed at lower rates than C. flexuosum from sites which were sheltered from wave action. These differences in palatability are mirrored in the formation of stable borders between coralline flats and C. flexuosum of the sheltered morphology, and the ability of C. flexuosum of the exposed morphology to survive in the coralline flats habitat. The fish fauna of the Cape Rodney to Okakari Point Marine Reserve was shown to be different from that of a nearby area. A number of species were more abundant within the Marine Reserve. Subsequent surveys showed that there were differences in abundances of 3 large carnivorous fishes among sites within the Marine Reserve, and that population size structure and the distance within which divers could approach one species, (Pagrus auratus), clearly varied between areas within the Marine Reserve. Mean standard length of P. auratus in the central marine reserve was 40% larger than that of P. auratus outside the central marine reserve, and the average minimum approach distance was 70% less in the central marine reserve. Feeding of fish by humans in the central part of the Marine Reserve was suggested to be the main cause of the differences in responses to divers. Population size structure of, and crevice occupancy by, E. chloroticus, clearly differed between the Marine Reserve and an adjacent area, with bimodal population size structures and a 10 mm greater size of crevice occupancy occurring in the Marine Reserve. The implications of these findings for extrapolating from experiments done in one area to other areas are discussed. The major biological components of rocky reef habitats identified in this study were broadly similar to those identified in previous studies in northeastern New Zealand, and have parallels in overseas studies. Long term changes to the flora of rocky reefs in northeastern New Zealand have occurred, and appear to persist by a mechanism which had previously been discounted. Similar processes to those observed in overseas studies appear to maintain habitats (consistent recruitment of algae or urchins to habitats which they dominate), or cause them to change from one habitat state to another (e.g. grazing outbreaks by urchins). However, the predictability of the persistence of these habitats at a particular site appears to be low. Further, the precise mechanisms whereby habitats may change from one to another may also be unpredictable. I argue that there is little scope for general statements concerning the spatial and temporal occurrence, or mode, of habitat transitions on temperate subtidal reefs. This study emphasises the value of repeated descriptions of patterns of abundance, and highlights problems of extrapolation and generalisation in marine ecology. Insufficient information exists at present to comment adequately on the persistence of subtidal habitat types. This may in part stem from the types of information which have been collected in the past. Methodological problems with the use of quadrats to sample densities of organisms in areas of differing topography are therefore addressed. In conclusion, it is suggested that sampling protocols which incorporate a variety of information, gathered over as wide an area, and as intensively as possible, should be used in future research of this type.

The eggs and larvae of the New Zealand snapper Pagrus auratus are pelagic with early buoyancy provided by dilute body fluids. The swimbladder begins to develop on the third day after hatch from a dorsal evagination of the gut tube. Communication w1h the gut is lost on about the tenth day following pneumatic inflation at around day eight. At this age the gas gland system appears fully functional and capable of secreting gas. By the age of settlement at around 30 days the swimbladder is a fully functional replica of the adult form except for the lack of a resorbent capillary system which does not develop until later in juvenile life. The swimbladder of the adult is of the euphysoclist form with a dorsally located resorbent oval area and sits high in the pleural cavity. The ventral tunica externa is firmly attached to the connective tissue lining the pleural space. The adult swimbladder displaces 5.6% of the volume of the body and its volume is regulated to provide near neutral buoyancy. The connective tissue integument provides almost no restriction to volume changes brought about by vertical movements of the fish and the swimbladder obeys Boyle's Law for physiological pressure changes. The ability of the connective tissue of the tunica externa to accommodate large tissue strains is due to massive regular crimping of otherwise straight collagen fibrils allowing reversible extensions up to 130%. In all other respects however the tissue structure of the tunica externa is consistent with a tissue providing an active mechanical role. The fibrillar morphology and physicochemical properties of swimbladder collagen is consistent with the vertebrate type I form however there are interesting variations in collagen form distributed throughout the swimbladder. Fibrillar morphology of the highly extensible tunica interna is significantly different to that of the tunica externa and appears to play very little mechanical rote. The extensibilty of the tunica externa appears to be regulated by physiological stress and related to the past history of tissue strain.

The impact of no-take marine reserves on spiny lobster, Jasus edwardsii, populations and the adjacent lobster fishery was assessed in a study that determined: the response of lobster populations to protection, if lobsters within marine reserves moved out into the surrounding fishery, examined the behavioural characteristic of lobsters that contributed to their recovery and spillover, and contrasted catch characteristics around a north-east New Zealand marine reserve with 2 unprotected sites. Surveys of 4 no-take marine reserves of different ages and 4 unprotected control sites confirmed that J. edwardsii increase in mean size and abundance within protected areas. Total lobster density was estimated to increase by 6.1% per year of protection. The relationship between age of reserve and the density of lobsters above the legal size limit (>100 mm carapace length) was complicated by depth related interactions between reserves, due to seasonal changes in the depth distribution of lobsters and differences in the timing of surveys among locations. However, density increases in legal sized lobsters were greater than those of the overall population. Mean size of protected lobsters increased in a non-linear fashion, reflecting the asymptotic growth characteristics of the species. Mean carapace length of lobsters increased by 11.24 mm after 3 years of protection and only by 16.25 mm after 2l years of protection. Corresponding increases in biomass (kg.500 m-2) and egg production (eggs.500 m-2) were estimated to be 7.4% and 6.6% respectively per year of protection. A tag recapture program indicated that the limited scale of movements and relatively high site fidelity of mature J. edwardsii aided the recovery of lobster populations in protected areas. Of 737 lobsters tagged in and around the Leigh Marine Reserve,212 were subsequently resighted. Seventy percent of resighted lobsters were relocated less than 250 m along the shore from their initial site after a mean period of liberty of 146 (se = 13.42) days. However, seasonal offshore movements took lobsters beyond the seaward boundary of the reserve where they were susceptible to capture. Of the 521 lobsters tagged on inshore reefs within the Leigh Marine Reserve. l.9% were caught over the seaward boundary by commercial fishers, and 14.4% of the 181 lobsters tagged over the seaward boundary were resighted on inshore reefs within the reserve. Movements into or out of the reserve across the longshore boundaries were also recorded for 7 out of the 27 lobsters moving further than 250 m along the shore. Acoustic tracking confirmed that J. edwardsii have a high site fidelity, with tracked lobsters spending a median of 84% of their time at their home site. Twenty one percent of the 26 lobsters fitted with acoustic tags never left their tagging site and, of those that did leave 56% eventually returned. Lobsters moved up to 3.1km away from their home sites but managed to find their way back after periods of 1 to 103 days away. Five lobsters had strong associations with two separate sites and made repeated movements between these alternate home sites. The straight line distance between alternate home sites ranged from 200 m to 1.3 km, and the period between visits to their primary or secondary home sites ranged from 1 to 93 days. Movement activity varied throughout the year, and seasonal patterns differed between males and females. Females displayed one peak in movement activity per year, around the time of larval release in September-October. Males displayed a summer peak centred on January, and a winter peak centred on July. The onset of high movement activity was often accompanied by a shift to deeper water and l0 of the 14 lobsters tracked for over 6 months spent periods away from the inshore reef system. Exposed groups of lobsters were observed aggregating in offshore areas of sand and low lying patch reef during the day. Offshore aggregations were observed over 7 months of the year and lobsters within the aggregations displayed behaviour consistent with the use of mutual defence. The sexual composition of the aggregations reflected seasonal patterns in male and female movement rates. Male J. edwardsii dominated the aggregations in winter and summer; times when peak feeding rates of males held in captivity were also recorded. Females dominated the offshore aggregations in September-October when larvae are released. Seven of the 26 lobsters fitted with acoustic tags moved over the boundaries of the Leigh Marine Reserve and Tawharanui Marine Park during offshore movements. Despite the fact that there is no fishing access to inshore reefs within the Leigh Marine Reserve, no significant difference was detected between the catch per unit effort (kg.trap haul-1) of lobsters caught around the reserve, nearby coastal Leigh or Little Barrier Island. However, catches around the marine reserve contained fewer (P=0.0009) but larger lobsters than at Little Barrier Island. The catch characteristics of lobsters from coastal Leigh were intermediate between the other two sites. As access to inshore reefs around the Leigh Marine Reserve was limited to a small area at either end of the reserve, traps tended to be set in offshore locations and the sexual composition of the total catch around the Leigh Marine Reserve reflected the seasonal movements of males and females into, and out, offshore areas. At coastal Leigh and Little Barrier Island the location of traps was not restricted and greater use was made of coastal fringing reefs. As a result the sexual composition of the catch at these locations did not reflect the movement of various components of the lobster population into and out of specific habitats or locations. Overall, the results of this study suggest that relatively small (~ 5 km2) no-take marine reserves increase lobster biomass and egg production, without adversely affecting catch rates in the surrounding fishery. Marine reserves may therefore represent a viable management tool, which if used in conjunction with other management regimes, could provide a more precautionary approach to the management of the J. edwardsii fishery at minimal cost to the industry.

Orientador: Carlos Alberto Vicentini / Banca: Antonio de Castro Rodrigues / Banca: Fernanda Antunes Alves da Costa / Banca: Camila Contin Diniz de Almeida Francia / Banca: Reginaldo José Donatelli / Resumo: O conhecimento das características morfológicas do tubo digestivo, associado aos processos de digestão e absorção, é fundamental para a compreensão da fisiologia e nutrição de peixes, auxiliando no planejamento de dietas para proporcionar melhorias no manejo e sucesso em piscicultura. Assim, o objetivo do presente trabalho foi analisar as características ultraestruturais e citoquímicas do tubo digestivo de exemplares adultos de Hemisorubim platyrhynchos para embasar o cultivo em pisciculturas e preservação da espécie. H. platyrhynchos é uma espécie carnívora, distribuída nas bacias hidrográficas do Orinoco, Amazonas, Paraguai, Uruguai e Paraná. Este peixe apresenta grande potencial de consumo, devido ao tamanho dos animais e à qualidade da carne. Também é utilizado na piscicultura ornamental, devido ao padrão de coloração. Contudo, esta espécie encontra-se ameaçada de extinção no estado de São Paulo, apresentando estoque reduzido e populações isoladas. Assim, trinta exemplares foram eutanasiados e dissecados para a retirada de fragmentos do esôfago, estômago (ventrículo gástrico) com regiões cárdica, fúndica e pilórica e intestino (regiões anterior, medial, posterior e reto). Para os estudos ultraestruturais, fragmentos foram fixados em solução de Karnovsky modificada, pós-fixados em tetróxido de ósmio e destinados à rotina de inclusão de microscopia eletrônica de transmissão. Para os estudos citoquímicos, fragmentos de tecido foram fixados em soluções apropriadas e destinados para as seguintes técnicas citoquímicas: impregnação com tetróxido de ósmio e iodeto de zinco - ZIO (visando a análise de organelas membranosas); método ósmio-imidazol (para detecção de inclusões lipídicas), método para detecção de fosfatase ácida e alcalina e método para detecção de glicoconjugados ácidos (vermelho de rutênio). Essas técnicas possibilitaram uma análise detalhada das... / Abstract: The knowledge of morphological characteristics of the digestive tract, associated with the processes of digestion and absorption, it is essential to understanding the physiology and nutrition of fish, assisting in planning diets to provide better management and success in farming. Thus, the aim of this study is to analyze the ultrastructural and cytochemical features of the digestive tract of adult specimen of Hemisorubim platyrhynchos to support cultivation in fish farms and preservation of the species. H. platyrhynchos is a carnivorous specie, distributed in the basins of the Orinoco, Amazonas, Paraguay, Uruguay and Paraná. This fish presents great potential for consumption, due to the animal size and meat quality. It is also used for ornamental fish due to the staining pattern of this species. However, this species is endangered in the São Paulo state, with reduced inventory and isolated populations. Thus, thirty specimens were killed and dissected to remove fragments of the esophagus, stomach (gastric ventricle) with cardiac, fundic and pyloric regions and intestine (anterior, middle, posterior and rectum). For ultrastructural studies, fragments were fixed in modified Karnovsky solution, post-fixed in osmium tetroxide and destinated for inclusion in the transmission electron microscopy routine. For cytochemical studies, tissue samples were fixed on appropriate solutions and destined for the following cytochemical techniques: impregnation with zinc iodide-osmium tetroxide - ZIO (targeting analysis of membranous organelles), method osmium-imidazole (to detect of lipid droplets), method for detection of alkaline and acid phosphatase and method for detection of acid glycoconjugates (ruthenium red). These techniques enabled a detailed analysis of the cellular characteristics of the epithelial lining, aiding in the understanding of cell physiology along the digestive tract of H. platyrhynchos / Doutor

Made available in DSpace on 2016-04-01T17:54:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-11-13. Added 1 bitstream(s) on 2016-04-01T18:00:12Z : No. of bitstreams: 1 000859978.pdf: 6690998 bytes, checksum: 74088b1ef6cdab7c030cc72afbcf6d00 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O conhecimento das características morfológicas do tubo digestivo, associado aos processos de digestão e absorção, é fundamental para a compreensão da fisiologia e nutrição de peixes, auxiliando no planejamento de dietas para proporcionar melhorias no manejo e sucesso em piscicultura. Assim, o objetivo do presente trabalho foi analisar as características ultraestruturais e citoquímicas do tubo digestivo de exemplares adultos de Hemisorubim platyrhynchos para embasar o cultivo em pisciculturas e preservação da espécie. H. platyrhynchos é uma espécie carnívora, distribuída nas bacias hidrográficas do Orinoco, Amazonas, Paraguai, Uruguai e Paraná. Este peixe apresenta grande potencial de consumo, devido ao tamanho dos animais e à qualidade da carne. Também é utilizado na piscicultura ornamental, devido ao padrão de coloração. Contudo, esta espécie encontra-se ameaçada de extinção no estado de São Paulo, apresentando estoque reduzido e populações isoladas. Assim, trinta exemplares foram eutanasiados e dissecados para a retirada de fragmentos do esôfago, estômago (ventrículo gástrico) com regiões cárdica, fúndica e pilórica e intestino (regiões anterior, medial, posterior e reto). Para os estudos ultraestruturais, fragmentos foram fixados em solução de Karnovsky modificada, pós-fixados em tetróxido de ósmio e destinados à rotina de inclusão de microscopia eletrônica de transmissão. Para os estudos citoquímicos, fragmentos de tecido foram fixados em soluções apropriadas e destinados para as seguintes técnicas citoquímicas: impregnação com tetróxido de ósmio e iodeto de zinco - ZIO (visando a análise de organelas membranosas); método ósmio-imidazol (para detecção de inclusões lipídicas), método para detecção de fosfatase ácida e alcalina e método para detecção de glicoconjugados ácidos (vermelho de rutênio). Essas técnicas possibilitaram uma análise detalhada das... / The knowledge of morphological characteristics of the digestive tract, associated with the processes of digestion and absorption, it is essential to understanding the physiology and nutrition of fish, assisting in planning diets to provide better management and success in farming. Thus, the aim of this study is to analyze the ultrastructural and cytochemical features of the digestive tract of adult specimen of Hemisorubim platyrhynchos to support cultivation in fish farms and preservation of the species. H. platyrhynchos is a carnivorous specie, distributed in the basins of the Orinoco, Amazonas, Paraguay, Uruguay and Paraná. This fish presents great potential for consumption, due to the animal size and meat quality. It is also used for ornamental fish due to the staining pattern of this species. However, this species is endangered in the São Paulo state, with reduced inventory and isolated populations. Thus, thirty specimens were killed and dissected to remove fragments of the esophagus, stomach (gastric ventricle) with cardiac, fundic and pyloric regions and intestine (anterior, middle, posterior and rectum). For ultrastructural studies, fragments were fixed in modified Karnovsky solution, post-fixed in osmium tetroxide and destinated for inclusion in the transmission electron microscopy routine. For cytochemical studies, tissue samples were fixed on appropriate solutions and destined for the following cytochemical techniques: impregnation with zinc iodide-osmium tetroxide - ZIO (targeting analysis of membranous organelles), method osmium-imidazole (to detect of lipid droplets), method for detection of alkaline and acid phosphatase and method for detection of acid glycoconjugates (ruthenium red). These techniques enabled a detailed analysis of the cellular characteristics of the epithelial lining, aiding in the understanding of cell physiology along the digestive tract of H. platyrhynchos / FAPESP: 2012/16143-2

Made available in DSpace on 2014-06-11T19:22:56Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-09-14Bitstream added on 2014-06-13T19:28:28Z : No. of bitstreams: 1 andrade_bn_me_sjrp.pdf: 1389363 bytes, checksum: 36747e3d257e6ec1a1b68f4998a5fbef (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Neoplecostomus Eigenman & Eigenmann, (1888), Neoplecostominae, abriga espécies de cascudo de pequeno porte, com treze espécies válidas muito semelhantes morfologicamente e com populações restritas às cabeceiras de riachos. Dados moleculares recentes apontaram que apesar das aparentes semelhanças morfológicas, algumas populações do alto rio Paraná divergem geneticamente. Devido a esta e outras evidências, como dimorfismo sexual, padrões de placas divergentes e dados morfométricos e merísticos, espécies novas foram descritas para a bacia do alto rio Paraná. Neste trabalho, Neoplecostomus sp. n., da bacia do alto rio Tietê, drenagem do alto rio Paraná é descrita. A espécie nova difere de todas as outras espécies por apresentar dimorfismo sexual, com fêmeas apresentando maior largura mandibular, 16,2-18,2% no comprimento da cabeça (vs. 11,6-14,3% em machos) e maior número de dentes que machos, tanto no dentário 30-38 (vs. 12-18 em machos) (caráter compartilhado com Neoplecostomus langeanii), quanto no pré-maxilar 31-38 (vs. 14-21). Este caráter é o primeiro registro para um neoplecostomíneo. Difere também de todas as outras espécies pela presença de quatro a cinco placas entre o pré-frontal e frontal (vs. 1-3 nas outras espécies), e de todas as espécies do alto rio Paraná pela presença da placa lateronasal, que quando desenvolvida forma a borda lateral da narina. Adicionalmente uma descrição osteológica completa da espécie-tipo Neoplecostomus microps (Steindachner, 1876) é apresentada. Trazemos algumas considerações sobre Neoplecostomus ribeirensis (bacia do rio Ribeira de Iguape), uma vez que o posicionamento da espécie na filogenia de Neoplecostominae, nos trabalhos que abordam dados moleculares, mostra Neoplecostomus ribeirensis mais relacionado à Isbrueckerichthys que as demais espécies cogenéricas / Neoplecostomus Eigenman & Eigenmann, 1888 Neoplecostominae, shelter species of catfishes small, with thirteen valid species morphologically very similar and populations restricted to headwaters streams. Recent molecular data pointed out that despite the apparent morphological similarities, some populations in the upper rio Paraná basin genetically differ significantly. So, here we propose a new species Neoplecostomus sp. n. from the upper rio Tietê, upper rio Paraná drainage. The new species is distinguished from congeners by presenting sexual dimorphism, with females having greater width of mandible 16.2-18.2% in the length of the head (vs. 11.6-14.3% in males) and a greater number of teeth than males in both the dental 30-38 (vs. 12-18), as in the pre-maxillary 31-38 (vs. 14-21) (this is the first record of this dimorphism to a Neoplecostominae); present 4 to 5 plates between the frontal and prefrontal (vs. 1-3). Differs from all species of the rio Paraná by having the plate lateronasal, which when developed forms the lateral edge of the nostril. Additionally, a complete osteological description of the species type, Neoplecostomus microps (Steindachner, 1876), was performed. Also present some considerations about Neoplecostomus ribeirensis (rio Ribeira de Iguape basin), since it is most closely related to Isbrueckerichthys, that other cogenerics species

Made available in DSpace on 2014-06-11T19:22:57Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-02-18Bitstream added on 2014-06-13T19:28:33Z : No. of bitstreams: 1 ribeiro_md_me_sjrp.pdf: 709812 bytes, checksum: 80b549dd4196a531b3d10a3135bcc492 (MD5) / A condição estrutural do hábitat é um importante fator para as comunidades de peixes em riachos, sendo que vários estudos relatam alterações na riqueza, composição e padrões de abundância das espécies como resultado da variação da estrutura do hábitat. No presente estudo foram abordados como a diversidade funcional e composição funcional da ictiofauna sofrem influência da estrutura do hábitat. No capítulo 1 foi avaliada a relação entre as medidas de diversidade funcional (riqueza funcional, dispersão funcional e uniformidade funcional) e a riqueza de espécies e estrutura do hábitat. No capítulo 2 foram analisados quais atributos funcionais, dentre os testados, influenciam a composição de espécies de peixes como resposta a estrutura do hábitat. Para atender aos objetivos dos dois capítulos foram coletados, por meio de pesca elétrica, espécimes de peixes em 91 riachos do noroeste do Estado de São Paulo. Foram calculados 12 atributos funcionais obtidos a partir de proporções de 16 medidas corporais das 61 espécies coletadas. A caracterização física dos riachos foi feita através de estimativas visuais, em que foram obtidas dez variáveis que refletem a estrutura no interior dos riachos e no ecótono água/terra. No primeiro capítulo, as medidas de diversidade funcional relacionadas ao volume do espaço funcional ocupado e regularidade na ocupação desse espaço foram calculadas utilizando o pacote FD do software R. As variáveis que quantificam a estrutura do hábitat foram analisadas a partir de uma Análise de Componentes Principais (PCA), onde se verificou que os riachos estão ordenados, em um extremo, conforme a quantidade de gramíneas e areia, e, em outro extremo, conforme a quantidade de rochas, galhos e troncos, indicando a existência de um gradiente de estrutura do habitat entre os riachos analisados. As relações entre diversidade funcional e riqueza de... / Not available

Made available in DSpace on 2016-08-12T18:48:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-02-20. Added 1 bitstream(s) on 2016-08-12T18:50:53Z : No. of bitstreams: 1 000865793.pdf: 865655 bytes, checksum: 58291547456e07da5071b89bee757449 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Os grandes rios Neotropicais, com seus canais principais, seus canais secundários, lagoas marginais conectados e isolados dos cursos de água apresentam uma elevada diversidade de habitats. A grande variedade de habitats proporciona a formação de gradientes ambientais espacialmente heterogêneos, considerados de suma importância para a biodiversidade. Uma diversidade ambiental é comumente encontrada em águas doces Neotropicais e, mais especificamente, na América do Sul, como por exemplo, nas bacias hidrográficas do Amazonas e do Paraná. Os compartimentos espaciais são de grande importância para o desenvolvimento do ciclo de vida das comunidades aquáticas, e diversos estudos têm enfatizado que lagoas marginais podem desempenhar um papel fundamental para a reprodução, alimentação e crescimento de inúmeras espécies de peixes e outros organismos aquáticos. Porém, pouco se sabe sobre a dinâmica desses organismos em sistemas lóticos e sistemas lênticos marginais e eventuais interações numa mesma escala temporal. O objetivo deste estudo foi analisar e comparar a estrutura dos organismos aquáticos e a dinâmica trófica das assembleias de peixes em um sistema lótico (canal principal do rio) versus um sistema lêntico contíguo (lagoa marginal), nas estações seca e chuvosa. Os locais selecionados para este estudo foi o canal principal do rio frente a uma lagoa marginal, na bacia do alto rio Paranapanema. É considerado um dos mais importantes tributários do alto rio Paraná, com sua nascente localizada na Serra da Paranapiacaba, no Estado de São Paulo, Sudeste Brasileiro. O conjunto de organismos aquáticos responsáveis pela produção primária e secundária, como o fitoplâncton, zooplâncton, macrófitas e macroinvertebrados mostraram algumas diferenças quanto a sua composição comparando a biota do canal principal do rio com aquela da lagoa marginal, bem como nas duas épocas do ano. De modo geral, riqueza maior de... / The large Neotropical rivers, with their main channels, their secondary channels, oxbow lake connected and isolated from water courses have a high diversity of habitats. The large variety of habitats provides the formation of spatially heterogeneous environmental gradients, considered of great importance for biodiversity. An environmental diversity is commonly found in freshwater Neotropical, more specifically in South America, for example, in the basins of the Amazon and Paraná. Space compartments are of great importance for the development of life cycle of aquatic communities, and several studies suggest that lagoons can play a key role in reproduction, feeding and growth of numerous species of fish and other aquatic organisms. However, little is known about the dynamics of those bodies in river systems and oxbow lake systems and possible interactions in the same time scale. The objective of this study was to analyze and compare the structure of aquatic organisms and trophic dynamics of fish assemblages in a lotic system (main river channel) versus one contiguous lentic system (oxbow lake), in the dry and rainy seasons. The selected site for this study was the main river channel front to an oxbow lake, in the Upper Paranapanema River basin. It is considered one of the most important tributaries of the upper Paraná River, with its source located in the Paranapiacaba Mountain, State of São Paulo, Southeastern Brazil. The set of aquatic organisms responsible for primary and secondary production, such as phytoplankton, zooplankton, macrophytes and macroinvertebrates showed some differences in its composition compared to biota of the main river channel with that of the oxbow lake, as well as in the two seasons. In general, the higher rate richness occurred in the oxbow lake. The structure of fish assemblages also showed some differences when comparing the environments and periods of the year. A greater diversity of species in the main ...