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Guisla Boehs - One of the best experts on this subject based on the ideXlab platform.
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pathogens in crassostrea rhizophorae Ostreidae from farmed and natural stocks in bahia northeastern brazil
XVI Colacmar y XVI Senalmar Santa Marta 2015, 2015Co-Authors: Guisla Boehs, Mariane Dos Santos Aguiar LuzAbstract:Diseases can have a damaging effect on natural and farmed shellfish stocks and, worldwide, there have been many reports on the harm that it cause to the production. This study investigated pathogens in the oyster Crassostrea rhizophorae from mangrove swamps and from farmed stocks in the coast of Bahia, northeastern Brazil. Samples were taken in 2012 and 2013, being the oysters (n = 330), all measuring from 5 to 7 cm in height, were obtained from a long-line cultivation system and from roots of the red mangrove Rhizophora mangle . The oysters were opened and macroscopically examined and then fixed in Davidson's solution. The tissues were processed by use of conventional histological technique, with staining using Harris’s hematoxylin and eosin. There was no macroscopic evidence of parasites or clinical signs of diseases. Microscopic analysis identified the following pathogens: Rickettsiae -like organisms (RLOs), in the digestive gland, with prevalence (P) of 2 to 6%; Sphenophrya sp. (Ciliophora) (P: 2-6%), in the gills; Nematopsis sp. (Apicomplexa) (P: 44-94%), in several organs, and it was more common in oysters from the mangrove swamp (where this pathogen has a greater chance of completing its life cycle due the presence of crustaceans) than from the farmed stocks (p<0.05 by Chi-square test); Perkinsus sp. (Perkinsozoa) (P: 88-100%), mainly in the stomach and intestine, where it caused changes to the epithelium and hemocytic reaction; Urastoma sp. (Turbellaria) (P: 2-4%), in the gills; Bucephalus sp. (Digenea) (P: 2%), in the digestive gland, mantle and gonad, with parasitic castration; Tylocephalum sp. (Cestoda) (P: 2%), in digestive gland; and an unidentified copepod (P: 2-4%), in the palial cavity, next to the gills. The pathogens were not considered to be important with regard to the health of C. rhizophorae yet, but constant monitoring and studies can promote the sustainability of the oyster farming in the region.
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Ciclo reproductivo del ostión de manglar Crassostrea rhizophorae (Bivalvia: Ostreidae) en la Bahía de Camamu, Bahia, Brasil
Vicerractoría Investigación, 2011Co-Authors: Tiago Lenz, Guisla BoehsAbstract:El ostión de manglar es un importante recurso pesquero que se distribuye por toda la costa brasileña y una de las especies nativas con mayor potencial para maricultura. Este estudio tuvo como objetivo conocer las características reproductivas del ostión de manglar Crassostrea rhizophorae en el estero del Río Maraú, Bahía de Camamu, Bahia, Brasil. Las muestras fueran recolectadas mensualmente, entre agosto de 2006 y septiembre de 2007, en dos sitios. Las metodologías utilizadas fueron el análisis histológico de las gónadas y el cálculo de rendimiento de carne. La temperatura del agua durante el período de estudio varió de 23.5°C a 30°C y la salinidad osciló entre 15 y 35ups. La altura de los ostiones examinados varió de 27 a 102mm (n=437). Hubo predominancia de hembras en las poblaciones de ambos sitios. Los análisis de estadios gonádicos demostraron que el proceso de reproducción de C. rhizophorae en el estero del Río Maraú es continuo durante el año, sin período de reposo sexual. El rendimiento de carne (R) fue de 8.0% a 17.7% (n=669). Los resultados de este estudio proveen informaciones para la captación de semilla e implantación de la ostricultura en la Bahía de Camamu.Reproductive cycle of the mangrove oyster Crassostrea rhizophorae (Bivalvia: Ostreidae) in Camamu Bay, Bahia, Brasil. The mangrove oyster Crassostrea rhizophorae is important fishery resource along the entire Brasilian coast with excellent potential for marine culture. The purpose of this paper was to examine the reproductive characteristics of the oyster of the Maraú river estuary in Camamu Bay, Bahia, Brasil. The samples were collected monthly, from September 2006 to August 2007, at two points (I and II) in Camamu Bay. At each site 20 oysters were collected for histological analysis, fixed in Davidson’s solution, embedded in paraffin, dehydrated in an ethanol series, sectioned (7μm thick) and stained with Harris hematoxylin and Eosin (HE). Additionally, 30 oysters were sampled, at each point, for a condition index analysis. The water temperature ranged from 23.5°C to 30°C and the salinity from 15 to 25 ups at Point I (Maraú) and from 25 to 35 at Point II (Tanque Island). The oyster’s height ranged from 30 to 92mm at Point I and from 27 to 102mm at Point II, with an average of 49.0mm±9.1 (n=230) and 49.9mm±9.9 (n=237), respectively. Among the sampled oysters at Point I, 59.1% were females, 31.3% males, 1.3% hermaphrodites and 8.2% of the oysters of undetermined sex. At Point II, 66.2% were females, 30.4% males, 0.8% hermaphrodites and 2.5% (n=237) of undetermined sex. The gonadic stage analysis indicated that the reproduction period of the C. rhizophorae in the Maraú Peninsula was continuous all year, without any regressive phase. The condition index (R) ranged from 8.0% to 17.7%. The peak periods of R coincided with the expressive oyster’s percentage in the maturation and liberation gametic stages. The results of these findings will contribute information for the oyster spat collection and to the process installation of the oyster culture in Camamu Bay. Rev. Biol. Trop. 59 (1): 137-149. Epub 2011 March 01
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ciclo reproductivo del ostion de manglar crassostrea rhizophorae bivalvia Ostreidae en la bahia de camamu bahia brasil
Revista De Biologia Tropical, 2009Co-Authors: Tiago Lenz, Guisla BoehsAbstract:El ostion de manglar es un importante recurso pesquero que se distribuye por toda la costa brasilena y una de las especies nativas con mayor potencial para maricultura. Este estudio tuvo como objetivo conocer las caracteristicas reproductivas del ostion de manglar Crassostrea rhizophorae en el estero del Rio Marau, Bahia de Camamu, Bahia, Brasil. Las muestras fueran recolectadas mensualmente, entre agosto de 2006 y septiembre de 2007, en dos sitios. Las metodologias utilizadas fueron el analisis histologico de las gonadas y el calculo de rendimiento de carne. La temperatura del agua durante el periodo de estudio vario de 23.5°C a 30°C y la salinidad oscilo entre 15 y 35ups. La altura de los ostiones examinados vario de 27 a 102mm (n=437). Hubo predominancia de hembras en las poblaciones de ambos sitios. Los analisis de estadios gonadicos demostraron que el proceso de reproduccion de C. rhizophorae en el estero del Rio Marau es continuo durante el ano, sin periodo de reposo sexual. El rendimiento de carne (R) fue de 8.0% a 17.7% (n=669). Los resultados de este estudio proveen informaciones para la captacion de semilla e implantacion de la ostricultura en la Bahia de Camamu.
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First record of parasitism in the mangrove oyster Crassostrea rhizophorae (Bivalvia: Ostreidae) at Jaguaribe River estuary--Ceará, Brazil.
Brazilian Journal of Biology, 2007Co-Authors: Rachel Costa Sabry, Tereza Cristina Vasconcelos Gesteira, Guisla BoehsAbstract:Mangrove oysters Crassostrea rhizophorae were sampled monthly in the estuary of Jaguaribe River, on the east coast of Ceara State, Brazil, between August, 2000 and December, 2001, making up 170 individuals. The water temperature varied from 26 to 30 °C and salinity from 21 to 42. The animals' size ranged from 3.4 to 7.2 cm height. Macroscopical and histopathological analyses were carried out in the oysters' tissues. The histological exams showed protozoans and metazoans of genera Nematopsis and Tylocephalum, respectively. Nematopsis prevalence varied from 60 to 100% and it was higher in the gills and mantle. The oocysts presented a mean size of 11.5 µm (±1.32) length and 9.1 µm (±1.06) width (n = 30), up to 3 oocysts/phagocyte having been observed. Several animals presented focal hemocitical reaction. The percentage of Tylocephalum was 1.7%. In spite of the high infection prevalence by Nematopsis, infected animals did not have their reproductive cycle impaired.
Abel Betanzosvega - One of the best experts on this subject based on the ideXlab platform.
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diagnostico de la produccion de ostion bivalvia Ostreidae en cuba ventajas de crassostrea virginica gmelin 1791 para la ostricultura diagnosis of oyster production bivalvia Ostreidae in cuba advantages of crassostrea virginica gmelin 1791 for the oys
Revista de Investigaciones Marinas, 2020Co-Authors: Jose Manuel Mazonsuastegui, Arturo Trippquezada, Abel BetanzosvegaAbstract:El ostion de mangle Crassostrea rhizophorae (Guilding, 1828), debido a su abundancia natural y rapido crecimiento, es el molusco bivalvo mas explotado comercialmente en Cuba, por pesca y cultivo. De mayor tamano promedio, C. virginica aparece en la captura comercial desde 2007 pero no se aprovecha en la ostricultura; el cultivo de esta especie pudiera garantizar un incremento productivo y mayores in- gresos. Segun indicadores productivos, se realizo un diagnostico de la produccion nacional de ostion con enfasis en siete provincias de mayor produccion (95%). La productividad se comparo (ANOVA) entre las especies de ostiones en Cuba. El objetivo es determinar las areas mas productivas de ostion y definir las ventajas de C. virginica para el cultivo. La produccion media anual de ostion (1112 t) durante 2000- 2017, es 50% inferior respecto a 1960-1999 (2226 t). El potencial de las areas ostricolas naturales no se utiliza de manera sostenible, y las provincias con costas a la plataforma suroriental mostraron mayor productividad. En estado silvestre, C. virginica mostro mayor peso y rendimiento en carne que C. rhizophorae . Los resultados pueden utili- zarse para lograr una actividad ostricola sustentable. Abstract T h e mangrove oyster Crassostrea rhizophorae (Guilding, 1828), due t o its natural abundance and rapid growth, is the most commercially exploited bivalve mollusc in Cuba, for fishing and farming. Of higher average size, C. virginica appears in the commercial catch since 2007 b u t not used in oyster farming, cultivation of this species could ensure increased production and higher incomes. According to productive indicators, a diagnosis of national oyster pro- duction was carried out with emphasis on the seven most productive provinces (95%). Pro- ductivity was compared (ANOVA) according to species of oysters in Cuba. The objective is to determine the most productive areas of oys- ter and define the advantages of C. virginica for cultivation. The average annual produc- tion of oyster (1112 t) during 2000-2017 is 50% lower than in 1960-1999 (2226 t). The potential of oyster areas not used sustainably, and the provinces bordering the southeastern platform showed higher productivity. In the wild, C. virginica showed greater weight and yield in meat than C. rhizophorae . The results can be used to achieve sustainable oyster farming. O y s t e r s , Crassostrea spp. , yield, oyster culture
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diagnostico de la produccion de ostion bivalvia Ostreidae en cuba ventajas de crassostrea virginica gmelin 1791 para la ostricultura diagnosis of oyster production bivalvia Ostreidae in cuba advantages of crassostrea virginica gmelin 1791 for the oyster culture
Revista de Investigaciones Marinas, 2020Co-Authors: Jose Manuel Mazonsuastegui, Arturo Trippquezada, Abel BetanzosvegaAbstract:El ostion de mangle Crassostrea rhizophorae (Guilding, 1828), debido a su abundancia natural y rapido crecimiento, es el molusco bivalvo mas explotado comercialmente en Cuba, por pesca y cultivo. De mayor tamano promedio, C. virginica aparece en la captura comercial desde 2007 pero no se aprovecha en la ostricultura; el cultivo de esta especie pudiera garantizar un incremento productivo y mayores in- gresos. Segun indicadores productivos, se realizo un diagnostico de la produccion nacional de ostion con enfasis en siete provincias de mayor produccion (95%). La productividad se comparo (ANOVA) entre las especies de ostiones en Cuba. El objetivo es determinar las areas mas productivas de ostion y definir las ventajas de C. virginica para el cultivo. La produccion media anual de ostion (1112 t) durante 2000- 2017, es 50% inferior respecto a 1960-1999 (2226 t). El potencial de las areas ostricolas naturales no se utiliza de manera sostenible, y las provincias con costas a la plataforma suroriental mostraron mayor productividad. En estado silvestre, C. virginica mostro mayor peso y rendimiento en carne que C. rhizophorae . Los resultados pueden utili- zarse para lograr una actividad ostricola sustentable. Abstract T h e mangrove oyster Crassostrea rhizophorae (Guilding, 1828), due t o its natural abundance and rapid growth, is the most commercially exploited bivalve mollusc in Cuba, for fishing and farming. Of higher average size, C. virginica appears in the commercial catch since 2007 b u t not used in oyster farming, cultivation of this species could ensure increased production and higher incomes. According to productive indicators, a diagnosis of national oyster pro- duction was carried out with emphasis on the seven most productive provinces (95%). Pro- ductivity was compared (ANOVA) according to species of oysters in Cuba. The objective is to determine the most productive areas of oys- ter and define the advantages of C. virginica for cultivation. The average annual produc- tion of oyster (1112 t) during 2000-2017 is 50% lower than in 1960-1999 (2226 t). The potential of oyster areas not used sustainably, and the provinces bordering the southeastern platform showed higher productivity. In the wild, C. virginica showed greater weight and yield in meat than C. rhizophorae . The results can be used to achieve sustainable oyster farming. O y s t e r s , Crassostrea spp. , yield, oyster culture
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oyster production and meat yield in crassostrea spp bivalvia Ostreidae in pinar del rio cuba
Ecosistemas y Recursos Agropecuarios, 2018Co-Authors: Abel Betanzosvega, Norberto Capetillopinar, Hever Latisnerebarragan, Nadia Livia Ortizcornejo, Jose Manuel MazonsuasteguiAbstract:The main fishing enterprise located in the province of Pinar del Rio, Cuba, markets oyster meat packed in brine bags of 460 g. The oysters come from natural bank fisheries (mangrove and bottom oyster), and from farms (mangrove oyster). Although the capture during 2009 – 2013 showed an increasing trend (50 to > 80 t), the oyster meat yields recorded values below (3.3 – 3.9 %), the acceptable minimums (4.9 %); in addition, a decrease in meat weight was observed between the packaging and commercialization, impacting productivity. The objectives of the study were the assessment of oyster exploitation based on the meat yield, and to assess the meat loss in the final packed product. A monthly and annual yield variation analysis and their relationship between fishery type and oyster size was performed. Meanwhile, the loss of meat was analyzed by different treatments of oyster / brine proportions. Significant differences (p < 0.05) of meat yield (%) by oyster species and size with a better performance in the farmed oysters were observed. The traditional proportion of packing for commercialization (meat / brine, 391 g / 69 g = 460 g), influenced the weight-loss of meat by leakage of interstitial fluid. After the treatments with different proportions of meat / brine, the proportion 1:1 showed the least loss of meat weight. The breach of commercial size and the lack of cleanliness of the oysters before the shell removing process, impacted the meat yield analysis during 2009-2013
Jose Manuel Mazonsuastegui - One of the best experts on this subject based on the ideXlab platform.
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diagnostico de la produccion de ostion bivalvia Ostreidae en cuba ventajas de crassostrea virginica gmelin 1791 para la ostricultura diagnosis of oyster production bivalvia Ostreidae in cuba advantages of crassostrea virginica gmelin 1791 for the oys
Revista de Investigaciones Marinas, 2020Co-Authors: Jose Manuel Mazonsuastegui, Arturo Trippquezada, Abel BetanzosvegaAbstract:El ostion de mangle Crassostrea rhizophorae (Guilding, 1828), debido a su abundancia natural y rapido crecimiento, es el molusco bivalvo mas explotado comercialmente en Cuba, por pesca y cultivo. De mayor tamano promedio, C. virginica aparece en la captura comercial desde 2007 pero no se aprovecha en la ostricultura; el cultivo de esta especie pudiera garantizar un incremento productivo y mayores in- gresos. Segun indicadores productivos, se realizo un diagnostico de la produccion nacional de ostion con enfasis en siete provincias de mayor produccion (95%). La productividad se comparo (ANOVA) entre las especies de ostiones en Cuba. El objetivo es determinar las areas mas productivas de ostion y definir las ventajas de C. virginica para el cultivo. La produccion media anual de ostion (1112 t) durante 2000- 2017, es 50% inferior respecto a 1960-1999 (2226 t). El potencial de las areas ostricolas naturales no se utiliza de manera sostenible, y las provincias con costas a la plataforma suroriental mostraron mayor productividad. En estado silvestre, C. virginica mostro mayor peso y rendimiento en carne que C. rhizophorae . Los resultados pueden utili- zarse para lograr una actividad ostricola sustentable. Abstract T h e mangrove oyster Crassostrea rhizophorae (Guilding, 1828), due t o its natural abundance and rapid growth, is the most commercially exploited bivalve mollusc in Cuba, for fishing and farming. Of higher average size, C. virginica appears in the commercial catch since 2007 b u t not used in oyster farming, cultivation of this species could ensure increased production and higher incomes. According to productive indicators, a diagnosis of national oyster pro- duction was carried out with emphasis on the seven most productive provinces (95%). Pro- ductivity was compared (ANOVA) according to species of oysters in Cuba. The objective is to determine the most productive areas of oys- ter and define the advantages of C. virginica for cultivation. The average annual produc- tion of oyster (1112 t) during 2000-2017 is 50% lower than in 1960-1999 (2226 t). The potential of oyster areas not used sustainably, and the provinces bordering the southeastern platform showed higher productivity. In the wild, C. virginica showed greater weight and yield in meat than C. rhizophorae . The results can be used to achieve sustainable oyster farming. O y s t e r s , Crassostrea spp. , yield, oyster culture
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diagnostico de la produccion de ostion bivalvia Ostreidae en cuba ventajas de crassostrea virginica gmelin 1791 para la ostricultura diagnosis of oyster production bivalvia Ostreidae in cuba advantages of crassostrea virginica gmelin 1791 for the oyster culture
Revista de Investigaciones Marinas, 2020Co-Authors: Jose Manuel Mazonsuastegui, Arturo Trippquezada, Abel BetanzosvegaAbstract:El ostion de mangle Crassostrea rhizophorae (Guilding, 1828), debido a su abundancia natural y rapido crecimiento, es el molusco bivalvo mas explotado comercialmente en Cuba, por pesca y cultivo. De mayor tamano promedio, C. virginica aparece en la captura comercial desde 2007 pero no se aprovecha en la ostricultura; el cultivo de esta especie pudiera garantizar un incremento productivo y mayores in- gresos. Segun indicadores productivos, se realizo un diagnostico de la produccion nacional de ostion con enfasis en siete provincias de mayor produccion (95%). La productividad se comparo (ANOVA) entre las especies de ostiones en Cuba. El objetivo es determinar las areas mas productivas de ostion y definir las ventajas de C. virginica para el cultivo. La produccion media anual de ostion (1112 t) durante 2000- 2017, es 50% inferior respecto a 1960-1999 (2226 t). El potencial de las areas ostricolas naturales no se utiliza de manera sostenible, y las provincias con costas a la plataforma suroriental mostraron mayor productividad. En estado silvestre, C. virginica mostro mayor peso y rendimiento en carne que C. rhizophorae . Los resultados pueden utili- zarse para lograr una actividad ostricola sustentable. Abstract T h e mangrove oyster Crassostrea rhizophorae (Guilding, 1828), due t o its natural abundance and rapid growth, is the most commercially exploited bivalve mollusc in Cuba, for fishing and farming. Of higher average size, C. virginica appears in the commercial catch since 2007 b u t not used in oyster farming, cultivation of this species could ensure increased production and higher incomes. According to productive indicators, a diagnosis of national oyster pro- duction was carried out with emphasis on the seven most productive provinces (95%). Pro- ductivity was compared (ANOVA) according to species of oysters in Cuba. The objective is to determine the most productive areas of oys- ter and define the advantages of C. virginica for cultivation. The average annual produc- tion of oyster (1112 t) during 2000-2017 is 50% lower than in 1960-1999 (2226 t). The potential of oyster areas not used sustainably, and the provinces bordering the southeastern platform showed higher productivity. In the wild, C. virginica showed greater weight and yield in meat than C. rhizophorae . The results can be used to achieve sustainable oyster farming. O y s t e r s , Crassostrea spp. , yield, oyster culture
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oyster production and meat yield in crassostrea spp bivalvia Ostreidae in pinar del rio cuba
Ecosistemas y Recursos Agropecuarios, 2018Co-Authors: Abel Betanzosvega, Norberto Capetillopinar, Hever Latisnerebarragan, Nadia Livia Ortizcornejo, Jose Manuel MazonsuasteguiAbstract:The main fishing enterprise located in the province of Pinar del Rio, Cuba, markets oyster meat packed in brine bags of 460 g. The oysters come from natural bank fisheries (mangrove and bottom oyster), and from farms (mangrove oyster). Although the capture during 2009 – 2013 showed an increasing trend (50 to > 80 t), the oyster meat yields recorded values below (3.3 – 3.9 %), the acceptable minimums (4.9 %); in addition, a decrease in meat weight was observed between the packaging and commercialization, impacting productivity. The objectives of the study were the assessment of oyster exploitation based on the meat yield, and to assess the meat loss in the final packed product. A monthly and annual yield variation analysis and their relationship between fishery type and oyster size was performed. Meanwhile, the loss of meat was analyzed by different treatments of oyster / brine proportions. Significant differences (p < 0.05) of meat yield (%) by oyster species and size with a better performance in the farmed oysters were observed. The traditional proportion of packing for commercialization (meat / brine, 391 g / 69 g = 460 g), influenced the weight-loss of meat by leakage of interstitial fluid. After the treatments with different proportions of meat / brine, the proportion 1:1 showed the least loss of meat weight. The breach of commercial size and the lack of cleanliness of the oysters before the shell removing process, impacted the meat yield analysis during 2009-2013
Sylvie Lapegue - One of the best experts on this subject based on the ideXlab platform.
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Complete mitochondrial DNA sequence of the European flat oyster Ostrea edulis confirms Ostreidae classification
BMC research notes, 2011Co-Authors: Gwenaelle Danic-tchaleu, Benjamin Morga, Sylvie LapegueAbstract:Abstract Background Because of its typical architecture, inheritance and small size, mitochondrial (mt) DNA is widely used for phylogenetic studies. Gene order is generally conserved in most taxa although some groups show considerable variation. This is particularly true in the phylum Mollusca, especially in the Bivalvia. During the last few years, there have been significant increases in the number of complete mitochondrial sequences available. For bivalves, 35 complete mitochondrial genomes are now available in GenBank, a number that has more than doubled in the last three years, representing 6 families and 23 genera. In the current study, we determined the complete mtDNA sequence of O. edulis , the European flat oyster. We present an analysis of features of its gene content and genome organization in comparison with other Ostrea , Saccostrea and Crassostrea species. Results The Ostrea edulis mt genome is 16 320 bp in length and codes for 37 genes (12 protein-coding genes, 2 rRNAs and 23 tRNAs) on the same strand. As in other Ostreidae, O. edulis mt genome contains a split of the rrnL gene and a duplication of trnM . The tRNA gene set of O. edulis , Ostrea denselamellosa and Crassostrea virginica are identical in having 23 tRNA genes, in contrast to Asian oysters, which have 25 tRNA genes (except for C. ariakensis with 24). O. edulis and O. denselamellosa share the same gene order, but differ from other Ostreidae and are closer to Crassostrea than to Saccostrea . Phylogenetic analyses reinforce the taxonomic classification of the 3 families Ostreidae, Mytilidae and Pectinidae. Within the Ostreidae family the results also reveal a closer relationship between Ostrea and Saccostrea than between Ostrea and Crassostrea . Conclusions Ostrea edulis mitogenomic analyses show a high level of conservation within the genus Ostrea , whereas they show a high level of variation within the Ostreidae family. These features provide useful information for further evolutionary analysis of oyster mitogenomes.
Inna M Sokolova - One of the best experts on this subject based on the ideXlab platform.
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tissue specific accumulation of cadmium in subcellular compartments of eastern oysters crassostrea virginica gmelin bivalvia Ostreidae
Aquatic Toxicology, 2005Co-Authors: Inna M Sokolova, Amy H Ringwood, C JohnsonAbstract:Abstract Cadmium distribution was studied in different subcellular fractions of gill and hepatopancreas tissues of eastern oysters Crassostrea virginica. Oysters were exposed for up to 21 days to low sublethal Cd concentrations (25 μg L−1). Gill and hepatopancreas tissues were sampled and divided into organelle fractions and cytosol by differential centrifugation. Organelle content of different fractions was verified by activities of marker enzymes, citrate synthase and acid phosphatase for mitochondria and lysosomes, respectively. In both tissue types, there was a significant accumulation of cadmium in cytosol reaching 230–350 ng mg−1 protein. Among organelles, mitochondria were the main target for Cd bioaccumulation in gills (250–300 ng mg−1 protein), whereas in hepatopancreas tissues, the highest cadmium accumulation occurred in lysosomes (90–94 ng mg−1 protein). Although 75–83% of total cadmium burden was associated with the cytosol reflecting high volume fraction of this compartment, Cd concentrations in organelle fractions reached levels that could cause dysfunction of mitochondria and lysosomes. Organ- and organelle-specific patterns of cadmium bioaccumulation support our previous in vivo studies, which showed adverse effects of cadmium exposures on mitochondrial oxidation in gills and on the lysosomal system of hepatopancreas. This may have important implications for the development of biomarkers of effect for heavy metals and for understanding the mechanisms of toxic effects of metals.
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cadmium effects on mitochondrial function are enhanced by elevated temperatures in a marine poikilotherm crassostrea virginica gmelin bivalvia Ostreidae
The Journal of Experimental Biology, 2004Co-Authors: Inna M SokolovaAbstract:SUMMARY Marine intertidal mollusks, such as oysters, are exposed to multiple stressors in estuaries, including varying environmental temperature and levels of trace metals, which may interactively affect their physiology. In order to understand the combined effects of cadmium and elevated temperature on mitochondrial bioenergetics of marine mollusks, respiration rates and mitochondrial volume changes were studied in response to different cadmium levels (0–1000 μmol l –1 ) and temperatures (15, 25 and 35°C) in isolated mitochondria from the eastern oyster Crassostrea virginica acclimated at 15°C. It was found that both cadmium and temperature significantly affect mitochondrial function in oysters. Elevated temperature had a rate-enhancing effect on state 3 (ADP-stimulated) and states 4 and 4+ (representative of proton leak) respiration, and the rate of temperature-dependent increase was higher for states 4 and 4+ than for state 3 respiration. Exposure of oyster mitochondria to 35°C resulted in a decreased respiratory control and phosphorylation efficiency (P/O ratio) compared to that of the acclimation temperature (15°C), while an intermediate temperature (25°C) had no effect. Cadmium exposure did not lead to a significant volume change in oyster mitochondria in vitro . Low levels of cadmium (1–5 μmol l –1 ) stimulated the rate of proton leak in oyster mitochondria, while not affecting ADP-stimulated state 3 respiration. In contrast, higher cadmium levels (10–50 μmol l –1 ) had little or no effect on proton leak, but significantly inhibited state 3 respiration by 40–80% of the control rates. Elevated temperature increased sensitivity of oyster mitochondria to cadmium leading to an early inhibition of ADP-stimulated respiration and an onset of complete mitochondrial uncoupling at progressively lower cadmium concentrations with increasing temperature. Enhancement of cadmium effects by elevated temperatures suggests that oyster populations subjected to elevated temperatures due to seasonal warming or global climate change may become more susceptible to trace metal pollution, and vice versa .
