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This study investigates the factors affecting larval and postlarval survival and growth of some de capod crustaceans with special emphasis on diets. Investigations were concentrated on the influence o live and artificial diets on larval growth, survival, development and trypsM activity of a cominerciall, important marine penaeid shrimp Penaeus indicus and a freshwater prawn Macrobrachium rosenber gij. In addition, feeding behaviour, gastroevacuation time, trypsM activity of other decapod species wen also studied. Live mixed microalgae Tetraselmis chuii and Skeletonema costatum at 60-70 cells PI-1 promote( highest larval survival, fastest growth and development in P. indicus in comparison to single algal spe cies. Rhinomonas reticulata neither alone nor in combination with other algal species was suitable a! food for the shrimp larvae, A water salinity (S) of 25 ppt was optimal for larval and postlarval cultun of this penaeid species. Postlarvae (PL) of P. indicus reared at lower salinities between PL7 and PL& (20-30 ppt) had a significantly (P<0.05) higher survival and a better growth than those at higher wate salinities. Early PL resisted sudden salinity change of 10 ppt, but required an adaptation period fo greater salinity changes, 10 ppt S was lethal to animals at around PL40-45. A free-living nematode Panagrellus redivivus was found to be a suitable alternative for live algai and Artemia in the culture of P. indicus. The nematodes gave good survival, but lower growth than al gaelArtemia from PZI to PLI. Larval growth and survival were significantly improved when the larvai were fed on either nematodes plus algal co-feeds or liPid-enriched nematodes. Pigmented- (astaxanthin nematodes also improved survival and colour of P. indicus larvae in comparison to non-pigmented ones Conventional live diets were also completely replaced using microencapsulated diets (MED) fo the culture of P. indicus, Like the nematodes, MED as a sole feed resulted In lower survival, slowe growth and development in comparison to algaelArtemia. Addition of 15 cells gl-1 frozen algae signifi cantly improved growth and survival during larval development. The larvae fed MED plus algal co feeds had significantly (P<0.05) higher trypsm activity than those fed MED as a sole feed. Similarly provision of 15 cells gl-' algae with nematodes for only 24h or 48h resulted in significant increase H trypsin activity and improved survival and growth to levels comparable to those obtained from al gaelArtemia. It appears that the presence of an algal diet is necessary to induce larval trypsin activity Mi P. indicus at early protozoeal stages, but algae do not influence trypsin at mysts stages. Results sugges that both nematodes and formulated diets lack gut enzyme stimulants and are less digestible than al gaelArtemia diets. When freeze-dried algal materials were incorporated into MED, it was found tha algal substances which trigger larval digestive enzymes were retained within the capsules. Whether thi will improve growth and survival of penaeid larvae remains to be examined. In contrast to penaeid larvae, a complete replacement of live Artemia with nematodes or artificia diets was not possible for the culture of caridean M rosenbergii and PaIdemon elegans larvae. Fo both species, only a partial replacement was achieved from Z4/5 to metamorphosis by using formulateA diets. It was found that these larvae have very low trypsin activity levels between ZI and Z4/5, but th, levels increase sharply afterwards, coinciding with a vast increase in the hepatopancreas. This sharl increase in digestive enzyme activities and longer food retention time enable these larvae to survive oj less digestible formulated diets. A comparison of specific trypsin activity in several larval decapod crustaceans shows a pattein with high levels in herbivores, low levels in carnivores and intermediate levels M omnivores. Herbivor penaeid larvae (P. indicus) and copepods (Temora longicornis and Centropages typicus) rely on hig digestive enzyme activities to extract nutrients from less digestible algae, whereas carnivorous larvaE the lobsters (Homarus gammarus and Nephrops norvegicus) and carideans (M. rosenbergii and .1 elegans) have limited enzymatic capacity and hence require large and easily digestible prey, but rests long starvation periods. Omnivorous mysis penaeid larvae and Carcinus maenas have intermediat levels of digestive enzymes and are able to transfer from herbivorous to omnivorous feeding. To datE only decapod larvae which show high trypsm activity can be successfidly reared to metamorphosis o: formulated feeds. Inclusion of algal material, as a gut enzyme stimulant, for penaeid protozoeal stage and pre-digested ingredients for later stages into feeds are proposed.

Resumo: O presente trabalho teve como objetivo investigar as variações que ocorrem nos ovários do camarão Macrobrachium olfersi durante a época reprodutiva, por meio de análises morfohistológicas em nível macro e microscópico. As fêmeas em período reprodutivo foram capturadas no Rio Ribeira de Iguape, litoral sul do estado de São Paulo, Brasil. As observações macroscópicas permitiram a determinação de três fases de maturação gonadal: a) em desenvolvimento (ED), onde os ovários apresentaram coloração variando de verde claro à verde oliva, estando apoiados na parte posterior do estômago encobrindo toda esta região, b) desenvolvido (DE), com coloração verde escura e preenchendo toda a cavidade cefalotorácica dorsal e c) desovado (DV), com coloração pardo-amarelada e tamanho menor em relação as demais fases, estando apoiado somente sobre o hepatopâncreas. A análise histológica permitiu classificar os ovócitos em estágios que variam de I a V de acordo com o tamanho, o aspecto citoplasmático, a observação da vesícula germinal e a granulação do vitelo. Verificou-se que na fase de maturação dos ovários designada como ED, observou-se a presença de ovócitos do estágio I ao IV, na fase DE encontraram-se, somente, ovócitos do estágio V e na fase DV, foi observado ovócitos dos estágios I a III. Os resultados do presente estudo demonstraram todas as fases do ciclo vitelogênico de M. olfersi durante a época reprodutiva. Sendo detectados cinco estágios celulares durante as três fases de desenvolvimento gonadal, porém em quantidades variadas / Abstract: The present study had the objective to investigate the modifications in Macrobrachium olfersi prawns ovaries during reproductive season through macro and microscopic morphological analysis. The females were captured in Ribeira de Iguape River (south coast of São Paulo, Brazil). By macroscopic observation three gonadal maturation phases could be determined: a) in maturation/in development (ID), ovaries that present a coloration that varies from light green to olive green; b) developed/mature (DE), presenting dark green color and c) totally spawned (SP), presenting yellowish brown color and smaler than in the other phases, being located on the hepatopancreas. By histological analysis oocytes could be classified in stages I to V according to the size; the cytoplasmatic aspect; the germinal vesicle and the yolk granulation. It was found that on the maturation phase of the ovaries known as ID, was observed the presence of oocytes from stage I to IV, at the DE phase, was founding only oocytes of stage V and at the DV phase, was observed oocytes of stages I to III. The results of this study showed all phases of the vitellogenic cycle of M. olfersi during the reproductive season. Being detected five cellular stages during the three phases of gonadal development, but in varying amounts / Orientador: Osmar Malaspina / Coorientador: Giovana Bertini / Banca: Pablo Henrique Nunes / Banca: Adriane Cristina Araújo Braga / Mestre

The western king prawn (Penueus Zarisulcutus) is one of the most economically valuable species of crustacean in Australia. The experiment was carried out for 60 days to determine the growth, survival, haemolymph osmolality and organosomatic indices of the western lung prawn (2.95 f 0.26 g mean initial weight) reared at 10, 22, 34 and 46 g L of salinities. In addition, haemolymph osmolality and osmoregulatory capacity (OC) of the western king prawn (5.37 f 0.1 g mean initial weight) reared at salinities (10, 22, 34 and 46 g/L) were determined following 7, 14 and 21 minutes of air exposure and compared with the brown tiger prawn (P, esculentus). Mean final weight, total length, carapace length and specific growth rate (SGR) of the western king prawn were highest at a salinity of 34 g/L. Moult increments (in weight and total length) of the western king prawn were not significantly different (P > 0.05) when reared at four different salinities. Food conversion ratios were lowest in prawns reared at salinities of 22 and 34 g/L. Survival of the western king prawn was highest at a salinity of 22 g/L and lowest at a salinity of 10 g/L. Haemolymph osmolality of the western king prawn increased with an increase in salinity and weight. Isosmotic points of the western king prawn calculated from regression lines between haemolymph and medium osmolality were 28.87, 29.46 and 31.73 g / L at 0, 20 and 60 days of rearing (accordingly to 2.95 f 0.26; 4.02 f 0.47; 5.79 f 0.64 g body weight), respectively. Tail moisture content of the western king prawn decreased with the increase of salinity. After 60 days of rearing, the lowest hepatopancreas moisture content of the prawns was at a salinity of 22 gL. Wet weight and dry weight hepatosomatic indices of the prawns were highest when reared at a salinity of 22 gL. / Wet weight and dry weight tail muscle indices of the prawns were highest at a salinity of 34 gL. Isosmotic points of the western king prawn were 33.79; 33.29; 32.75 and 33.10 g/L at 0, 7, 14, and 21 minutes of air exposure, respectively. Isosmotic points of the brown tiger prawn were 30.89; 31.89; 32.09 and 31.07 g/L at 0, 7, 14, and 21 minutes of air exposure, respectively. Air exposure reduced OC of both the western king prawn and brown tiger prawn. OC of both species at a salinity of 10 giL was reduced significantly after 14 minutes of air exposure. Twenty-one minutes of air exposure did not change OC of the western king prawn reared at salinities of 22, 34 and 46 g/L. OC of brown tiger prawn reared at 22 g/L decreased after 21 minutes of air exposure while OC of the brown tiger prawn reared at 46 g/L decreased after 7 minutes of air exposure. The results indicate that both species spent less energy on osmoregulation at 34 gL salinity than at other salinities. The results suggest that the optimum salinity for rearing of western king prawns ranges from 22 g/L to 34 g/L. Salinities of 10 and 46 gL are unsuitable for rearing brown tiger prawns and salinity 10 g/L is unsuitable for rearing western king prawns. Furthermore, a salinity range from 30 g/L to 32 gL is suitable for the culture of brown tiger prawns.

No description available.

Made available in DSpace on 2014-06-11T19:23:00Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-07-13Bitstream added on 2014-06-13T19:49:24Z : No. of bitstreams: 1 giovannetti_n_me_rcla.pdf: 864791 bytes, checksum: c1c1f60c2d1f290e11d35aaadb9b1a51 (MD5) / O presente trabalho teve como objetivo investigar as variações que ocorrem nos ovários do camarão Macrobrachium olfersi durante a época reprodutiva, por meio de análises morfohistológicas em nível macro e microscópico. As fêmeas em período reprodutivo foram capturadas no Rio Ribeira de Iguape, litoral sul do estado de São Paulo, Brasil. As observações macroscópicas permitiram a determinação de três fases de maturação gonadal: a) em desenvolvimento (ED), onde os ovários apresentaram coloração variando de verde claro à verde oliva, estando apoiados na parte posterior do estômago encobrindo toda esta região, b) desenvolvido (DE), com coloração verde escura e preenchendo toda a cavidade cefalotorácica dorsal e c) desovado (DV), com coloração pardo-amarelada e tamanho menor em relação as demais fases, estando apoiado somente sobre o hepatopâncreas. A análise histológica permitiu classificar os ovócitos em estágios que variam de I a V de acordo com o tamanho, o aspecto citoplasmático, a observação da vesícula germinal e a granulação do vitelo. Verificou-se que na fase de maturação dos ovários designada como ED, observou-se a presença de ovócitos do estágio I ao IV, na fase DE encontraram-se, somente, ovócitos do estágio V e na fase DV, foi observado ovócitos dos estágios I a III. Os resultados do presente estudo demonstraram todas as fases do ciclo vitelogênico de M. olfersi durante a época reprodutiva. Sendo detectados cinco estágios celulares durante as três fases de desenvolvimento gonadal, porém em quantidades variadas / The present study had the objective to investigate the modifications in Macrobrachium olfersi prawns ovaries during reproductive season through macro and microscopic morphological analysis. The females were captured in Ribeira de Iguape River (south coast of São Paulo, Brazil). By macroscopic observation three gonadal maturation phases could be determined: a) in maturation/in development (ID), ovaries that present a coloration that varies from light green to olive green; b) developed/mature (DE), presenting dark green color and c) totally spawned (SP), presenting yellowish brown color and smaler than in the other phases, being located on the hepatopancreas. By histological analysis oocytes could be classified in stages I to V according to the size; the cytoplasmatic aspect; the germinal vesicle and the yolk granulation. It was found that on the maturation phase of the ovaries known as ID, was observed the presence of oocytes from stage I to IV, at the DE phase, was founding only oocytes of stage V and at the DV phase, was observed oocytes of stages I to III. The results of this study showed all phases of the vitellogenic cycle of M. olfersi during the reproductive season. Being detected five cellular stages during the three phases of gonadal development, but in varying amounts

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No description available.

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Many brackish water aquaculture ventures in Australia and overseas have established ponds in coastal regions with acid sulfate soils (ASS). Acid sulphate soils are known to leach relatively high concentrations of metals, acid (metal and H+ ion) and sulfur, however very little is known about how these leached elements affect the water quality of aquaculture ponds. The main objective of this thesis was to describe the hydrochemical processes controlling the water chemistry in the water column and sediment pore water in the studied aquaculture ponds over time and space. Water samples providing the spatio-temporal data were collected from the ponds with the use of adapted sampling methods commonly used in the groundwater environment. A transect of five nested piesometers was installed in two prawn ponds at Pimpama, south east Queensland, Australia. Each piesometer nest contained a multilevel with eight outtakes, a mini ?? horizontal, and a slotted piesometer. Water samples were collected from each nested piesometer on a bi-monthly basis over the prawn-growing season. The unstable elements and water quality variables (pH, Eh, DO, EC, water temperature) were measured in the field. Stable elements were analysed in the laboratory using ICP-OES and ICP-MS. Soil samples were collected at the end of the season for elemental analysis. A number of key sediment/water interactions and processes such as precipitation/dissolution reactions, oxidation-reduction reactions, photosynthesis, adsorption and seawater buffering were identified as important controls on pond water conditions. This is the first study to provide detailed hydrochemcial analysis of the pond water over time and space and aided in identifying that even shallow water bodies can be chemically heterogeneous. Analysis of the water and sediment highlighted the selection of metals that can be associated with ASS and that are mobilised from pond sediments under certain chemical conditions. In Pond 7 Al, As, Ni and Zn concentrations were generally higher at the beginning of the grow-out season. Variability of the metal concentration was observed between the water column (0 ?? 1500 mm) and the pore-water (0 - -1000 mm). The highest concentration of Al (1044 ??g/L) and Zn (104 ??g/L) were sampled in the water column (approximately 400 mm from the surface of the pond). The highest concentration of As (130 ??g/L) and Ni (73 ??g/L) were sampled in the pore water sediment (associated with ASS). Elevated Mn and Fe2+ concentrations were also associated with the sediment pore water. The highest concentrations of Mn and Fe2+ were 4717 ??g/L and 5100 ??g/L respectively. In Pond 10, Ni concentrations (167 ??g/L) were the highest at the beginning of the grow-out season. However, As (97 ??g/L), Al (234 ??g/L) and Zn (308 ??g/L) were most concentrated during the middle of the cycle. The highest mean concentrations of these elements are As (63 ??g/L), Al (91 ??g/L) and Zn (69 ??g/L) which are each associated with the sediment-water interface. These metals are integral in degrading the pond water quality and lead to a loss of beneficial algal blooms, a reduction in pond water pH, poor growth rates and high mortality in shrimp. It is also possible that the dissolved ions and precipitated compounds that are leached from the ASS are discharged into the adjacent coastal estuary of Moreton Bay. With knowledge obtained from this PhD study, effective management and treatment systems can be developed and implemented to minimise the impact of these soils on the pond system and the water discharging into natural coastal ecosystem.