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This project focussed on improving marine finfish aquaculture production in the Asia-Pacific regi... more This project focussed on improving marine finfish aquaculture production in the Asia-Pacific region by focussing on key constraints: improving hatchery technology to improve the availability of seedstock; evaluating the nutritional needs of groupers to support the development of compounded pellet diets; and improving communication and coordination of marine finfish aquaculture research and development activities in the Asia-Pacific region.
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• Aromatase inhibition is effective, but impractical for large-scale sex change of giant grouper.... more • Aromatase inhibition is effective, but impractical for large-scale sex change of giant grouper. • Giant grouper show primary male development in both AI and control groups, indicating they are diandric protogynous hermaphrodites. • Behavioural interactions established a social hierarchy which stimulated sex change. • Treatment averages would not have revealed the full effects of social dynamics on sex change. Conclusion Results
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Aquaculture, 2021
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Aquacultural …, 2006
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Aquacultural Engineering - AQUACULT ENG, 2006
A novel technique was developed for the flocculation of marine microalgae commonly used in aquacu... more A novel technique was developed for the flocculation of marine microalgae commonly used in aquaculture. The process entailed an adjustment of pH of culture to between 10 and 10.6 using NaOH, followed by addition of a non-ionic polymer Magnafloc LT-25 to a final concentration of 0.5mgL−1. The ensuing flocculate was harvested, and neutralised giving a final concentration factor of between 200- and 800-fold. This process was successfully applied to harvest cells of Chaetoceros calcitrans, C. muelleri, Thalassiosira pseudonana, Attheya septentrionalis, Nitzschia closterium, Skeletonema sp., Tetraselmis suecica and Rhodomonas salina, with efficiencies ≥80%. The process was rapid, simple and inexpensive, and relatively cost neutral with increasing volume (cf. concentration by centrifugation). Harvested material was readily disaggregated to single cell suspensions by dilution in seawater and mild agitation. Microscopic examination of the cells showed them to be indistinguishable from corre...
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Journal of fish biology, 2018
The giant grouper Epinephelus lanceolatus is an ecologically vulnerable species with high market ... more The giant grouper Epinephelus lanceolatus is an ecologically vulnerable species with high market demand. However, efforts to improve larval husbandry are hindered by a lack of knowledge surrounding larval developmental physiology. To address this shortfall, a transcriptomic approach was applied to larvae between 1 and 14 days post hatch (dph) to characterise the molecular ontogenesis of genes that influence appetite and digestion. Appetite regulating factors were detected from 1 dph, including neuropeptide Y, nesfatin-1, cocaine and amphetamine regulated transcript, cholecystokinin and pituitary adenylate cyclase activating peptide and the expression level of several genes changed sharply with the onset of exogenous feeding. The level of expression for proteases, chitinases, lipases and amylases typically followed one of two expression patterns, a general increase as development progressed, or an inverted U-shape with maximal expression at c. 6 dph. Similarly, the tendency among bot...
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Aquaculture, 2016
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Diseases of aquatic organisms, Jan 8, 2015
Infections with monogeneans of the Diplectanidae can limit productivity of and cause considerable... more Infections with monogeneans of the Diplectanidae can limit productivity of and cause considerable health issues for fish in aquaculture. To date, 9 species of diplectanids have been reported from the Asian sea bass or barramundi Lates calcarifer (Perciformes: Latidae) in the Asia-Pacific region. This study characterised the diplectanid parasite fauna found infecting wild and farmed barramundi from 5 localities in tropical Australia, including north Queensland and Western Australia. A combination of morphometric and comparative genetic analyses of partial 28S ribosomal RNA (28S rRNA) from specimens recovered were used to confirm their identity and to explore relationships with other diplectanids. These data revealed that a single, dominant species of diplectanid, Laticola paralatesi, infects wild and farmed Lates calcarifer in tropical Australia. Laticola lingaoensis Yang, Kritsky, Sun, Jiangying, Shi & Agrawal, 2006 is synonymised with L. seabassi (Wu, Li, Zhu & Xie, 2005) Domingues...
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FEMS Microbiology Letters, 1986
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Aquaculture Nutrition, 2002
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Aquaculture, 2005
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Aquaculture, 2002
Ten new diatom strains were isolated from coastal waters of Australia and their potential as feed... more Ten new diatom strains were isolated from coastal waters of Australia and their potential as feed species for aquaculture evaluated based on their cell size, division rate and biochemical composition. All strains were within the size range ingested by most filter feeders, i.e. 3–10 μm. Cellular growth rates of aerated 1.6-l cultures ranged from 0.5–0.7 divisions·day−1 (Papiliocellulus simplex CS-431, Nitzschia
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Aquacultural Engineering, 2006
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This project focussed on improving marine finfish aquaculture production in the Asia-Pacific regi... more This project focussed on improving marine finfish aquaculture production in the Asia-Pacific region by focussing on key constraints: improving hatchery technology to improve the availability of seedstock; evaluating the nutritional needs of groupers to support the development of compounded pellet diets; and improving communication and coordination of marine finfish aquaculture research and development activities in the Asia-Pacific region.
Bookmarks Related papers MentionsView impact
• Aromatase inhibition is effective, but impractical for large-scale sex change of giant grouper.... more • Aromatase inhibition is effective, but impractical for large-scale sex change of giant grouper. • Giant grouper show primary male development in both AI and control groups, indicating they are diandric protogynous hermaphrodites. • Behavioural interactions established a social hierarchy which stimulated sex change. • Treatment averages would not have revealed the full effects of social dynamics on sex change. Conclusion Results
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Aquaculture, 2021
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Aquacultural …, 2006
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Aquacultural Engineering - AQUACULT ENG, 2006
A novel technique was developed for the flocculation of marine microalgae commonly used in aquacu... more A novel technique was developed for the flocculation of marine microalgae commonly used in aquaculture. The process entailed an adjustment of pH of culture to between 10 and 10.6 using NaOH, followed by addition of a non-ionic polymer Magnafloc LT-25 to a final concentration of 0.5mgL−1. The ensuing flocculate was harvested, and neutralised giving a final concentration factor of between 200- and 800-fold. This process was successfully applied to harvest cells of Chaetoceros calcitrans, C. muelleri, Thalassiosira pseudonana, Attheya septentrionalis, Nitzschia closterium, Skeletonema sp., Tetraselmis suecica and Rhodomonas salina, with efficiencies ≥80%. The process was rapid, simple and inexpensive, and relatively cost neutral with increasing volume (cf. concentration by centrifugation). Harvested material was readily disaggregated to single cell suspensions by dilution in seawater and mild agitation. Microscopic examination of the cells showed them to be indistinguishable from corre...
Bookmarks Related papers MentionsView impact
Journal of fish biology, 2018
The giant grouper Epinephelus lanceolatus is an ecologically vulnerable species with high market ... more The giant grouper Epinephelus lanceolatus is an ecologically vulnerable species with high market demand. However, efforts to improve larval husbandry are hindered by a lack of knowledge surrounding larval developmental physiology. To address this shortfall, a transcriptomic approach was applied to larvae between 1 and 14 days post hatch (dph) to characterise the molecular ontogenesis of genes that influence appetite and digestion. Appetite regulating factors were detected from 1 dph, including neuropeptide Y, nesfatin-1, cocaine and amphetamine regulated transcript, cholecystokinin and pituitary adenylate cyclase activating peptide and the expression level of several genes changed sharply with the onset of exogenous feeding. The level of expression for proteases, chitinases, lipases and amylases typically followed one of two expression patterns, a general increase as development progressed, or an inverted U-shape with maximal expression at c. 6 dph. Similarly, the tendency among bot...
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Aquaculture, 2016
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Diseases of aquatic organisms, Jan 8, 2015
Infections with monogeneans of the Diplectanidae can limit productivity of and cause considerable... more Infections with monogeneans of the Diplectanidae can limit productivity of and cause considerable health issues for fish in aquaculture. To date, 9 species of diplectanids have been reported from the Asian sea bass or barramundi Lates calcarifer (Perciformes: Latidae) in the Asia-Pacific region. This study characterised the diplectanid parasite fauna found infecting wild and farmed barramundi from 5 localities in tropical Australia, including north Queensland and Western Australia. A combination of morphometric and comparative genetic analyses of partial 28S ribosomal RNA (28S rRNA) from specimens recovered were used to confirm their identity and to explore relationships with other diplectanids. These data revealed that a single, dominant species of diplectanid, Laticola paralatesi, infects wild and farmed Lates calcarifer in tropical Australia. Laticola lingaoensis Yang, Kritsky, Sun, Jiangying, Shi & Agrawal, 2006 is synonymised with L. seabassi (Wu, Li, Zhu & Xie, 2005) Domingues...
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FEMS Microbiology Letters, 1986
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Aquaculture Nutrition, 2002
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Aquaculture, 2005
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Aquaculture, 2002
Ten new diatom strains were isolated from coastal waters of Australia and their potential as feed... more Ten new diatom strains were isolated from coastal waters of Australia and their potential as feed species for aquaculture evaluated based on their cell size, division rate and biochemical composition. All strains were within the size range ingested by most filter feeders, i.e. 3–10 μm. Cellular growth rates of aerated 1.6-l cultures ranged from 0.5–0.7 divisions·day−1 (Papiliocellulus simplex CS-431, Nitzschia
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Aquacultural Engineering, 2006
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