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Noritaka Hirazawa - One of the best experts on this subject based on the ideXlab platform.
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the influence of different water temperatures on neobenedenia Girellae monogenea infection parasite growth egg production and emerging second generation on amberjack seriola dumerili carangidae and the histopathological effect of this parasite on fis
Aquaculture, 2010Co-Authors: Noritaka Hirazawa, Ryoko Takano, Hiroko Hagiwara, Mitsuyo Noguchi, Minoru NaritaAbstract:This study investigated: 1) the influence of water temperature on Neobenedenia Girellae (capsalid) infection, parasite growth, egg production and emerging second generation on the host amberjack Seriola dumerili (Carangidae) in Experiment I, and 2) changes in the infection level of N. Girellae on S. dumerili, and the parasite growth and histopathological changes of S. dumerili skin infected with N. Girellae at different water temperatures in Experiment II. In Experiment I, the length of parasites from S. dumerili reared at 30 °C was significantly greater than parasites from fish reared at 20 °C or 25 °C. Parasite eggs were observed at 13 days from larval attachment at 20 °C, 8 days at 25 °C, and 6 days at 30 °C, thus the number of eggs laid by parasites from S. dumerili reared at 30 °C was greater than that from fish reared at 20 °C and 25 °C. The next generation N. Girellae larvae were identified on fish reared at 25 °C and 30 °C at 13 days after exposure to oncomiracidia and the number of larval parasites on fish reared at 30 °C was significantly higher than that on fish reared at 25 °C. In Experiment II, at 8 days and 12 days after exposure to oncomiracidia, the differences in the number of parasites among fish reared at 20 °C, 25 °C and 30 °C were not statistically significant. However, the number of parasites on fish reared at 30 °C was significantly lower than that on fish reared at 20 °C and 25 °C at 16 days after the exposure, suggesting that their life span after larval attachment on the host was shorter with increasing water temperature and ability of the parasites to infect on the host was comparable among these temperatures. Seriola dumerili epidermis with attached N. Girellae thinned markedly in groups reared at 25 °C and 30 °C, whereas the epidermis of S. dumerili in the group reared at 20 °C did not, compared with that of uninfected fish throughout the trial. Therefore, at higher water temperatures, frequent measures for controlling the parasites would be required. Any information on N. Girellae life cycle is potentially important in developing a strategy for its control.
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the effect of oral antibiotic treatment and freshwater bath treatment on susceptibility to neobenedenia Girellae monogenea infection of amberjack seriola dumerili and yellowtail s quinqueradiata hosts
Aquaculture, 2009Co-Authors: Yasuhiro Ohno, Fumi Kawano, Noritaka HirazawaAbstract:Amberjack Seriola dumerili (Carangidae) and yellowtail S. quinqueradiata, important commercial fish in Japan, are susceptible to parasitic infection with Neobenedenia Girellae (Capsalidae) when cultured in floating net cages. To prevent N. Girellae infection, a 2- to 5-min freshwater dip is often practiced. In addition, many bacterial diseases, such as vibriosis, pasteurellosis, streptococcosis, mycobacteriosis and nocardiosis, also afflict cultivated Seriola species and oral administration of antibiotics is often necessary. The present study investigated whether oral antibiotics and freshwater bath treatments will influence the susceptibility to N. Girellae infection of these two species. The infection intensity and growth of N. Girellae on S. dumerili and S. quinqueradiata did not differ significantly between the control group and oxytetracycline, florfenicol, ampicillin, erythromycin or sulfamonomethoxine-treated groups, suggesting that oral antibiotics do not influence the susceptibility to N. Girellae infection of S. dumerili or S. quinqueradiata hosts when administered at recommended doses. In contrast, freshwater bath treatment for 2 min significantly increased N. Girellae infection on both S. dumerili and S. quinqueradiata compared to control groups exposed to oncomiracidia in the same aquarium. Thus, the susceptibility to N. Girellae infection of these species was shown to be increased by freshwater bath treatment. These results may be well considered for controlling N. Girellae infections when cultivating Seriola species.
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effect of neobenedenia Girellae monogenea infection on host amberjack seriola dumerili carangidae
Aquaculture, 2009Co-Authors: Takeshi Hirayama, Fumi Kawano, Noritaka HirazawaAbstract:Abstract This study was designed to investigate: 1) the distribution of Neobenedenia Girellae (Capsalidae) on host amberjack Seriola dumerili (Carangidae) and growth of the parasite during infection; 2) the influence of different N. Girellae exposure levels on S. dumerili growth; and 3) the histopathological skin changes of S. dumerili infected with N. Girellae at the different parasite densities. N. Girellae were mostly found on pelvic and pectoral fins of S. dumerili at 1 and 3 days after exposure of S. dumerili to N. Girellae oncomiracidia. The parasites were primarily found on the skin surface at 6 days after exposure, and all mature N. Girellae specimens were found on the skin surface at 9 and 12 days after exposure. These results show that N. Girellae migrated from the fins to the skin surface during parasite growth. The growth of S. dumerili infected with N. Girellae was significantly slower compared with that of uninfected fish when the number of infected parasites was more than 0.285 ± 0.042/cm2 fish surface showing that N. Girellae infections hindered the growth of the host fish. In addition, the feed conversion ratio was positively correlated with the number of infected parasites on fish. Furthermore, the thickness of S. dumerili epidermis with attached N. Girellae was negatively correlated with both the N. Girellae infection duration and the number of infected parasites. Thus, larger N. Girellae caused more severe infections on host S. dumerili. These results in this study could be applied to control N. Girellae infections and to promote stable S. dumerili production in aquaculture.
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susceptibility by amberjack seriola dumerili yellowtail s quinqueradiata and japanese flounder paralichthys olivaceus to neobenedenia Girellae monogenea infection and their acquired protection
Aquaculture, 2008Co-Authors: Yasuhiro Ohno, Fumi Kawano, Noritaka HirazawaAbstract:This study investigated: 1) susceptibility differences to infection by Neobenedenia Girellae (Capsalidae) between amberjack Seriola dumerili (Carangidae), yellowtail S. quinqueradiata and Japanese flounder Paralichthys olivaceus (Paralichthyidae); 2) growth and egg production of N. Girellae on each fish species; 3) acquired protection of each fish species against this parasite. The number of N. Girellae on S. dumerili was significantly higher than on S. quinqueradiata and P. olivaceus when these fishes were exposed to oncomiracidia in the same aquarium. Neobenedenia Girellae growth on S. dumerili was fastest and, thus the number of eggs laid by parasites on S. dumerili was greater than on the other two species. Seriola dumerili and P. olivaceus, which were previously infected with N. Girellae and treated by freshwater bath, acquired partial protection against re-infection by N. Girellae. The relative re-infection of three S. dumerili individuals out of eleven individuals was markedly low compared with the initial infection, and the relative initial infection and re-infection on two P. olivaceus out of eleven individuals was markedly low. The results of this study could be useful to control N. Girellae infections when cultivating S. dumerili, S. quinqueradiata and P. olivaceus.
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Antiparasitic effect of calcium and magnesium ion-free buffer treatments against a common monogenean Neobenedenia Girellae.
Parasitology, 2006Co-Authors: Hiroshi Ohashi, Naoko Umeda, Noritaka Hirazawa, Yuichi Ozaki, C. Miura, Takeshi MiuraAbstract:This study investigated a new effective method for controlling the capsalid monogenean Neobenedenia Girellae. We examined in vitro and in vivo the effect on the percentage survival of N. Girellae in buffers containing different metallic ions. Decreased survival was observed in buffer solutions lacking two ions. In particular, the percentage survival of N. Girellae was significantly decreased after 10 min exposure to buffer containing neither Ca(2+) nor Mg(2+). Transmission electron microscopic observations showed that treatment with this buffer disrupted intercellular junctions. This significant effect on percentage survival of N. Girellae using Ca(2+)/Mg(2+)-free buffer was confirmed in an in vivo assay. Ca(2+)/Mg(2+)-free buffer had no effect on the condition of the host, spotted halibut Verasper variegates (Pleuronectidae). These results suggest that treatment with Ca(2+)/Mg(2+)-free buffer is a new effective control method, which could replace existing control methods.
Belinda G. Curley - One of the best experts on this subject based on the ideXlab platform.
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a review of the biology and ecology of key fishes targeted by coastal fisheries in south east australia identifying critical knowledge gaps required to improve spatial management
Reviews in Fish Biology and Fisheries, 2013Co-Authors: Belinda G. Curley, Alan R Jordan, Will F Figueira, Vanessa C ValenzuelaAbstract:Knowledge of the population biology, life-history ecology and scales of pre and post-settlement movement of marine species are needed to inform effective conservation management strategies, particularly when spatial information is required for management purposes such as zoning in Marine Protected Areas. This review provides the most current summary from primary and grey literature on the biology and ecology of several coastal fishes of economic and ecological significance in south-east Australia; identifies key knowledge gaps which may impede the development of effective spatial management; and recommends future research directions and methods. Reviewed species are luderick (Girella tricuspidata), eastern rock blackfish (Girella elevata), yellowfin bream (Acanthopagrus australis), tarwhine (Rhabdosargus sarba), snapper (Pagrus auratus), red morwong (Cheilodactylus fuscus) and eastern blue grouper (Achoerodus viridis). The species have a diverse range of life-histories and population traits, and selected parameters were well studied in several species, such as growth (blue groper, luderick, yellowfin bream, tarwhine, snapper), post-settlement movement (red morwong), and larval ecology (yellowfin bream). However, empirical data on levels of pre- and post-settlement connectivity and real-time movements are not available for most species, and this represents a significant gap for improved spatial management. A multidisciplinary approach incorporating a range of methods including acoustic tracking and telemetry, otolith chemistry, intergenerational markers, and biophysical modelling will provide a more comprehensive understanding of life history parameters, movement and connectivity at scales relevant to MPA planning and monitoring.
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Isolation of microsatellites from Girella tricuspidata
Molecular Ecology Notes, 2006Co-Authors: Belinda G. Curley, Michael R. GillingsAbstract:Microsatellites were isolated from Girella tricuspidata (Girellidae) and screened for 64 individuals collected from coastal reefs in New South Wales, Australia. All seven loci tested were highly polymorphic, having seven to 42 alleles with average heterozygosities between 0.44 and 1.0. One locus (GT1N8) had a significant excess of homozygotes, probably due to the presence of null alleles. These microsatellite loci should be informative for examining population genetics of this species.
Vanessa C Valenzuela - One of the best experts on this subject based on the ideXlab platform.
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a review of the biology and ecology of key fishes targeted by coastal fisheries in south east australia identifying critical knowledge gaps required to improve spatial management
Reviews in Fish Biology and Fisheries, 2013Co-Authors: Belinda G. Curley, Alan R Jordan, Will F Figueira, Vanessa C ValenzuelaAbstract:Knowledge of the population biology, life-history ecology and scales of pre and post-settlement movement of marine species are needed to inform effective conservation management strategies, particularly when spatial information is required for management purposes such as zoning in Marine Protected Areas. This review provides the most current summary from primary and grey literature on the biology and ecology of several coastal fishes of economic and ecological significance in south-east Australia; identifies key knowledge gaps which may impede the development of effective spatial management; and recommends future research directions and methods. Reviewed species are luderick (Girella tricuspidata), eastern rock blackfish (Girella elevata), yellowfin bream (Acanthopagrus australis), tarwhine (Rhabdosargus sarba), snapper (Pagrus auratus), red morwong (Cheilodactylus fuscus) and eastern blue grouper (Achoerodus viridis). The species have a diverse range of life-histories and population traits, and selected parameters were well studied in several species, such as growth (blue groper, luderick, yellowfin bream, tarwhine, snapper), post-settlement movement (red morwong), and larval ecology (yellowfin bream). However, empirical data on levels of pre- and post-settlement connectivity and real-time movements are not available for most species, and this represents a significant gap for improved spatial management. A multidisciplinary approach incorporating a range of methods including acoustic tracking and telemetry, otolith chemistry, intergenerational markers, and biophysical modelling will provide a more comprehensive understanding of life history parameters, movement and connectivity at scales relevant to MPA planning and monitoring.
Matthew D. Taylor - One of the best experts on this subject based on the ideXlab platform.
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Intra-population trends in the maturation and reproduction of a temperate marine herbivore Girella elevata across latitudinal clines.
Journal of fish biology, 2015Co-Authors: Jerom R. Stocks, Charles A. Gray, Matthew D. TaylorAbstract:Latitudinal variation in the reproductive characteristics of a temperate marine herbivore, rock blackfish Girella elevata, was examined from three regions of the south-eastern Australian coast. Biological sampling covered 780 km of coastline, including the majority of the species distribution. The sampling range incorporated three distinct oceanographic regions of the East Australian Current, a poleward-flowing western boundary current of the Southern Pacific Gyre and climate-change hotspot. Girella elevata are a highly fecund, group synchronous (multiple batch)-spawner. Mean fork length (LF ) and age at maturity were greater for females than males within all regions, with both male and female G. elevata of the southern region maturing at a greater size and age than those from the central region. Estimates of batch fecundity (FB ) were greatest in the northern and southern regions, relative to the central region where growth rates were greatest. Significant positive relationships were observed between FB and LF , and FB and total fish mass. Gonado-somatic indices indicated latitudinal synchrony in spawning seasonality between G. elevata at higher latitudes, spawning in the late austral spring and summer. A late or prolonged spawning period is evident for G. elevata from the northern region. Juvenile recruitment to intertidal rock pools within the central and southern regions was synchronous with the spawning season, however, no juveniles were found within the northern region. The implications of latitudinal variation in reproductive characteristics are discussed in the context of climate and oceanographic conditions of south-east Australia.
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Out in the wash: spatial ecology of a temperate marine shallow rocky-reef species derived using acoustic telemetry
Marine and Freshwater Research, 2015Co-Authors: Jerom R. Stocks, Charles A. Gray, Matthew D. TaylorAbstract:Characterising the movement and habitat affinities of fish is a fundamental component in understanding the functioning of marine ecosystems. A comprehensive array of acoustic receivers was deployed at two near-shore coastal sites in south-eastern Australia, to examine the movements, activity-space size and residency of a temperate rocky-reef, herbivorous species Girella elevata. Twenty-four G. elevata individuals were internally tagged with pressure-sensing acoustictransmittersacrossthesetwoarraysandmonitoredforupto550days.Anexistingnetworkofcoastalreceiverswas used to examine large-scale movement patterns. Individuals exhibited varying residency, but all had small activity-space sizes within the arrays. The species utilised shallow rocky-reef habitat, displaying unimodal or bimodal patterns in depth use.Apositivecorrelationwasobservedbetweenwindspeedandthedetectiondepthoffish,withfishbeinglikelytomove to deeper water to escape periods of adverse conditions. Detection frequency data, corrected using sentinel tags, generally illustrated diurnal behaviour. Patterns of habitat usage, residency and spatial utilisation highlighted the susceptibility of G. elevata to recreational fishing pressure. The results from the present study will further contribute to the spatial informationrequiredinthezoningofeffectivemarineprotectedareas,andourunderstandingoftemperatereeffishecology. Additional keywords: Girella elevata, home range, marine protected areas, movement, residency, residency index, sentinel transmitters.
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Summary statistics of diurnal frequency of detections on acoustic receivers for luderick, Girella tricuspidata, passively tracked in Jervis Bay, New South Wales.
2013Co-Authors: Adrian M. Ferguson, Euan S. Harvey, Matthew D. Taylor, Nathan A. KnottAbstract:Summary statistics of diurnal frequency of detections on acoustic receivers for luderick, Girella tricuspidata, passively tracked in Jervis Bay, New South Wales.
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Map of Jervis Bay, New South Wales, where the study was conducted.
2013Co-Authors: Adrian M. Ferguson, Euan S. Harvey, Matthew D. Taylor, Nathan A. KnottAbstract:Luderick, Girella tricuspidata, were caught and released at 2 sites within a sanctuary zone (GBN = Greenfields Beach North and GBS = Greenfields Beach South) and 2 sites within Booderee National Park (BNP) (BP = Bristol Point and HW = Hole in the Wall). Boxed areas, except for BNP, represent sanctuary zones (no fishing allowed). The semi-circle area at C, (Creswell), represents a special purpose zone and the site of an artificial harbour. Empty circles represent receiver locations and a 300 m detection area. Rocky reef (light grey) and seagrass (hatch) areas are shown. Inset map of Australia is also shown.
Nathan A. Knott - One of the best experts on this subject based on the ideXlab platform.
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Herbivore abundance, site fidelity and grazing rates on temperate reefs inside and outside marine reserves
Journal of Experimental Marine Biology and Ecology, 2016Co-Authors: Adrian M. Ferguson, Euan S. Harvey, Nathan A. KnottAbstract:Abstract A key objective of marine reserves is to maintain ecological processes important to the functioning of marine ecosystems. Grazing by tropical herbivores contributes to maintaining resilient coral reefs and marine reserves are critical in conserving herbivores and the functional role they provide. Less is known, however, about the effects of marine reserves on herbivorous fish and their role on temperate reefs. This study evaluated the potential for marine reserves to enhance grazing by herbivores on temperate reefs in Jervis Bay Marine Park, Australia. First, the movement patterns of a dominant grazer, luderick Girella tricuspidata , were determined using acoustic telemetry to assess the potential effects of marine reserves on G. tricuspidata . Second, the size and abundance of G. tricuspidata and other grazers (rock blackfish Girella elevata and silver drummer Kyphosus sydneyanus ) was quantified on shallow subtidal reefs inside and outside marine reserves using a diver operated stereo-video system. Finally, grazing rates were quantified inside and outside marine reserves using video cameras. Luderick G. tricuspidata exhibited strong site fidelity on shallow subtidal reefs and was significantly larger and more abundant within marine reserves. Rock blackfish G. elevata was significantly more abundant in one of four marine reserves, although showed no difference in size between zones. Silver drummer K. sydneyanus was significantly larger in marine reserves, although not significantly more abundant. On shallow subtidal reefs, G. tricuspidata was the dominant grazer compared to other girellids and kyphosids, accounting for > 97% of total algal bites (predominantly on algal turfs). Grazing rates were higher on average within marine reserves (although not significantly higher) and there was a positive correlation between the relative abundance of G. tricuspidata and number of algal bites, indicating grazing intensity increased with abundance. The findings in this study demonstrate the clear potential for greater grazing by herbivores within temperate marine reserves. This study also suggests that exploitation of targeted herbivores on temperate reefs is significant and marine reserves can reduce this impact and allow it to be measured via reference areas.
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Does the abundance of girellids and kyphosids correlate with cover of the palatable green algae, Ulva spp.? A test on temperate rocky intertidal reefs.
Journal of fish biology, 2015Co-Authors: Adrian M. Ferguson, Euan S. Harvey, Matthew J. Rees, Nathan A. KnottAbstract:This study assessed whether the abundance of girellids and kyphosids was related to cover of the palatable green algae, Ulva australis and Ulva compressa, on rocky intertidal reefs in Jervis Bay, New South Wales, Australia. No relationship was found between Ulva spp. cover and abundance of Girella tricuspidata, Girella elevata and Kyphosus sydneyanus during a period of relatively low Ulva spp. cover (i.e. February 2011 to March 2011), but during a period of significantly higher Ulva spp. cover (i.e. October 2011 to November 2011) there was a strong correlation between Ulva spp. cover and G. tricuspidata abundance. Spatial analysis indicated that the abundance of G. tricuspidata was consistent across time, suggesting G. tricuspidata were not moving between reefs in response to variation in Ulva spp. cover between periods but rather that large schools of G. tricuspidata resided on reefs that had relatively higher Ulva spp. cover at certain times of the year.
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Summary statistics of diurnal frequency of detections on acoustic receivers for luderick, Girella tricuspidata, passively tracked in Jervis Bay, New South Wales.
2013Co-Authors: Adrian M. Ferguson, Euan S. Harvey, Matthew D. Taylor, Nathan A. KnottAbstract:Summary statistics of diurnal frequency of detections on acoustic receivers for luderick, Girella tricuspidata, passively tracked in Jervis Bay, New South Wales.
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Map of Jervis Bay, New South Wales, where the study was conducted.
2013Co-Authors: Adrian M. Ferguson, Euan S. Harvey, Matthew D. Taylor, Nathan A. KnottAbstract:Luderick, Girella tricuspidata, were caught and released at 2 sites within a sanctuary zone (GBN = Greenfields Beach North and GBS = Greenfields Beach South) and 2 sites within Booderee National Park (BNP) (BP = Bristol Point and HW = Hole in the Wall). Boxed areas, except for BNP, represent sanctuary zones (no fishing allowed). The semi-circle area at C, (Creswell), represents a special purpose zone and the site of an artificial harbour. Empty circles represent receiver locations and a 300 m detection area. Rocky reef (light grey) and seagrass (hatch) areas are shown. Inset map of Australia is also shown.