Yu Luo, Wenfu Zhang, A. Fang, Ronghui Ye, Gang Ren, Gen-fang Zhang
ABSTRACT Selective breeding of mussels based on nacre color forms the basis for cultivating freshwater pearls with specific colors, as the color of cultured pearls is mainly determined by the nacre color of the donor mussel. In this study, the nacre colors of four selected Hyriopsis cumingii strains (blue, red, golden, and white) were measured and analyzed. The results showed that the three nacre color parameters L*, a*, and b* significantly differed (P < 0.01) between the four H. cumingii strains. Two principal components (PC1 and PC2) were extracted based on a principal component analysis, and their cumulative contribution rate ranged from 92.81% to 93.44%. The color parameters a* and b* had the greatest influences on PC1 and PC2, respectively, indicating that these two color parameters were the main factors contributing to the nacre color differences of the four strains. The nacre color parameters of the four H. cumingii strains were also investigated extensively using discriminant analysis, and the discrimination accuracies of the four strains were 76.7%, 80.0%, 72.5%, and 100.0%. Reflectance spectrum analysis showed that the nacre reflectance spectra of the four H. cumingii strains differed considerably and the spectral reflectance curves of the different nacre colors were clearly separated, indicating that spectral analysis represents an effective method for identifying different H. cumingii strains.
{"title":"Nacre Color and Reflectance Spectrum Analyses of Four Selected Strains of Mussels, Hyriopsis cumingii","authors":"Yu Luo, Wenfu Zhang, A. Fang, Ronghui Ye, Gang Ren, Gen-fang Zhang","doi":"10.2983/035.041.0207","DOIUrl":"https://doi.org/10.2983/035.041.0207","url":null,"abstract":"ABSTRACT Selective breeding of mussels based on nacre color forms the basis for cultivating freshwater pearls with specific colors, as the color of cultured pearls is mainly determined by the nacre color of the donor mussel. In this study, the nacre colors of four selected Hyriopsis cumingii strains (blue, red, golden, and white) were measured and analyzed. The results showed that the three nacre color parameters L*, a*, and b* significantly differed (P < 0.01) between the four H. cumingii strains. Two principal components (PC1 and PC2) were extracted based on a principal component analysis, and their cumulative contribution rate ranged from 92.81% to 93.44%. The color parameters a* and b* had the greatest influences on PC1 and PC2, respectively, indicating that these two color parameters were the main factors contributing to the nacre color differences of the four strains. The nacre color parameters of the four H. cumingii strains were also investigated extensively using discriminant analysis, and the discrimination accuracies of the four strains were 76.7%, 80.0%, 72.5%, and 100.0%. Reflectance spectrum analysis showed that the nacre reflectance spectra of the four H. cumingii strains differed considerably and the spectral reflectance curves of the different nacre colors were clearly separated, indicating that spectral analysis represents an effective method for identifying different H. cumingii strains.","PeriodicalId":50053,"journal":{"name":"Journal of Shellfish Research","volume":"41 1","pages":"223 - 228"},"PeriodicalIF":1.3,"publicationDate":"2022-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45553765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jong-Seop Shin, Hyoun Joong Kim, J. Hwang, M. Kwon, Young-Ghan Cho, Kwang-Sik Choi
ABSTRACT Outbreaks of oyster diseases caused by the World Organization for Animal Health (OIE)-listed protozoan pathogens have been a global concern for several decades. With the wide application of species-specific and sensitive polymerase chain reaction (PCR) techniques, it is now well known that even the Pacific oyster, insusceptible to Perkinsus marinus, Bonamia ostreae, Bonamia exitiosa could act as a carrier host. Furthermore, one of the transmission pathways of oyster pathogens includes anthropogenic activities, such as the discharge of ballast water or hull attachment during international maritime shipping. In this survey, OIE-listed pathogens, including B. ostreae, B. exitiosa, and Marteilia refringens were screened in the Pacific oysters growing in small bays off the south coast of Korea using PCR with OIE-recommended species- or genus-specific (Bonamia) primers. The survey sampled 1980 oysters from 35 sites in small bays in the south, where more than 95% of the national productions are yielded. The PCR screening indicated that none of the oysters screened in this study were positive for B. ostreae, B. exitiosa, P. marinus, and M. refringens. This study first investigated the OIE-listed protozoan pathogens in the Pacific oysters culturing in Korea, and the results indicated that the Pacific oysters raised on the south coast of Korea are free from those OIE-listed pathogens. For secure and sustainable oyster farming on the south coast, however, regular monitoring of such invasive oyster pathogens is recommended, as the international maritime trade activities are increasing in Korea.
{"title":"Monitoring of Oie-Listed Parasitic Pathogens in the Pacific Oyster (Crassostrea gigas) on the South Coast of Korea Using Species-Specific PCR","authors":"Jong-Seop Shin, Hyoun Joong Kim, J. Hwang, M. Kwon, Young-Ghan Cho, Kwang-Sik Choi","doi":"10.2983/035.041.0203","DOIUrl":"https://doi.org/10.2983/035.041.0203","url":null,"abstract":"ABSTRACT Outbreaks of oyster diseases caused by the World Organization for Animal Health (OIE)-listed protozoan pathogens have been a global concern for several decades. With the wide application of species-specific and sensitive polymerase chain reaction (PCR) techniques, it is now well known that even the Pacific oyster, insusceptible to Perkinsus marinus, Bonamia ostreae, Bonamia exitiosa could act as a carrier host. Furthermore, one of the transmission pathways of oyster pathogens includes anthropogenic activities, such as the discharge of ballast water or hull attachment during international maritime shipping. In this survey, OIE-listed pathogens, including B. ostreae, B. exitiosa, and Marteilia refringens were screened in the Pacific oysters growing in small bays off the south coast of Korea using PCR with OIE-recommended species- or genus-specific (Bonamia) primers. The survey sampled 1980 oysters from 35 sites in small bays in the south, where more than 95% of the national productions are yielded. The PCR screening indicated that none of the oysters screened in this study were positive for B. ostreae, B. exitiosa, P. marinus, and M. refringens. This study first investigated the OIE-listed protozoan pathogens in the Pacific oysters culturing in Korea, and the results indicated that the Pacific oysters raised on the south coast of Korea are free from those OIE-listed pathogens. For secure and sustainable oyster farming on the south coast, however, regular monitoring of such invasive oyster pathogens is recommended, as the international maritime trade activities are increasing in Korea.","PeriodicalId":50053,"journal":{"name":"Journal of Shellfish Research","volume":"41 1","pages":"189 - 194"},"PeriodicalIF":1.3,"publicationDate":"2022-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41603025","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. D. R. Simental‐Anguiano, Y. Torres-Rojas, F. Galván‐Magaña, A. Tripp-Quezada
ABSTRACT The upper Gulf of California, Mexico is a marine protected area (MPA), considered important for the conservation and protection of species. The present study assessed the resource–consumer interactions of two ray species (Rhinoptera steindachneri and Hypanus dipterurus), to know the importance of shellfish in the food-web dynamics of two predators present in this MPA. A total of 33 prey species for R. steindachneri and 48 prey species for H. dipterurus were recorded. The bivalve Tellina subtrigona (%IRI = 99.5) was the most important species in the diet of R. steindachneri; whereas the gastropod Mitrella dorma (%IRI = 32.7) was the primary prey of H. dipterurus. The ray R. steindachneri had a lower Shannon's index of diversity (H' = 0.49) than H. dipterurus (H' = 1.41). Based on Amundsen's graphical method, R. steindachneri have a specialist feeding strategy; whereas H. dipterurus presented a mixed strategy that includes both specialist and generalist organisms. However, the trophic specialization evidenced by these rays may reflect the grouping behavior of their prey, which tend to form large aggregations. Both ray species are secondary consumers (TLR. steindachneri = 3.10 and TL H. dipterurus = 3.12) of shellfish. Nevertheless, there is a low similarity in the prey species composition between them (ANOSIM: R = 0.47), indicating that these two ray species have different diets, and therefore, each ray species has specific resource–consumer interactions. This information allows to understand the importance of shellfish in the food-web dynamics in the ecosystem and MPA effectiveness in the upper Gulf of California for species at risk, like ray species.
{"title":"Importance of Shellfish in the Diet of Two Ray Species (Rhinoptera steindachneri and Hypanus dipterurus) in the Upper Gulf of California","authors":"M. D. R. Simental‐Anguiano, Y. Torres-Rojas, F. Galván‐Magaña, A. Tripp-Quezada","doi":"10.2983/035.041.0215","DOIUrl":"https://doi.org/10.2983/035.041.0215","url":null,"abstract":"ABSTRACT The upper Gulf of California, Mexico is a marine protected area (MPA), considered important for the conservation and protection of species. The present study assessed the resource–consumer interactions of two ray species (Rhinoptera steindachneri and Hypanus dipterurus), to know the importance of shellfish in the food-web dynamics of two predators present in this MPA. A total of 33 prey species for R. steindachneri and 48 prey species for H. dipterurus were recorded. The bivalve Tellina subtrigona (%IRI = 99.5) was the most important species in the diet of R. steindachneri; whereas the gastropod Mitrella dorma (%IRI = 32.7) was the primary prey of H. dipterurus. The ray R. steindachneri had a lower Shannon's index of diversity (H' = 0.49) than H. dipterurus (H' = 1.41). Based on Amundsen's graphical method, R. steindachneri have a specialist feeding strategy; whereas H. dipterurus presented a mixed strategy that includes both specialist and generalist organisms. However, the trophic specialization evidenced by these rays may reflect the grouping behavior of their prey, which tend to form large aggregations. Both ray species are secondary consumers (TLR. steindachneri = 3.10 and TL H. dipterurus = 3.12) of shellfish. Nevertheless, there is a low similarity in the prey species composition between them (ANOSIM: R = 0.47), indicating that these two ray species have different diets, and therefore, each ray species has specific resource–consumer interactions. This information allows to understand the importance of shellfish in the food-web dynamics in the ecosystem and MPA effectiveness in the upper Gulf of California for species at risk, like ray species.","PeriodicalId":50053,"journal":{"name":"Journal of Shellfish Research","volume":"41 1","pages":"291 - 299"},"PeriodicalIF":1.3,"publicationDate":"2022-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45398164","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Liqin Liu, Shijie Zhao, Yao Zhang, Maoting Wang, Yunjun Yan, Zhengming Lü, L. Gong, Bingjian Liu, Yinghui Dong, Zhijin Xu
ABSTRACT Vitellogenin (Vg) is the precursor of yolk protein, which plays an important role in the reproduction and development of oviparous animals. In this study, vitellogenin1 (Vg1) from Sepiella japonica was cloned and characterized, and its potential function in ovarian development was investigated. The full-length cDNAs of Vg1 was 5853 base pair (bp) that encoded 748 amino acids. Sequence analysis revealed that the overall protein sequence of Vg1 shared 66% identity with that of Uroteuthis edulis. Analyses with quantitative reverse transcription polymerase chain reaction (RT-qPCR) showed that the highest expression of Vg1 occurred in the ovary. As ovary developed, the expression of Vg1 increased in both ovary and liver from oogonia phase (I) to interstitial growth phase (III), and reached to the peak value at stage III. In addition, we examined the effects of Gonadotropin-releasing hormone (GnRH) on Vg1 expression in the ovary and liver were examined. The data showed that GnRH increased mRNA expression of Vg1, indicating that exogenous GnRH initially affected Vg1 expression and then influenced ovarian maturation. This study suggests that Vg1 might be involved in ovarian development in cephalopods.
{"title":"Identification of Vitellogenin 1 Potentially Related to Reproduction in the Cephalopod, Sepiella japonica","authors":"Liqin Liu, Shijie Zhao, Yao Zhang, Maoting Wang, Yunjun Yan, Zhengming Lü, L. Gong, Bingjian Liu, Yinghui Dong, Zhijin Xu","doi":"10.2983/035.041.0209","DOIUrl":"https://doi.org/10.2983/035.041.0209","url":null,"abstract":"ABSTRACT Vitellogenin (Vg) is the precursor of yolk protein, which plays an important role in the reproduction and development of oviparous animals. In this study, vitellogenin1 (Vg1) from Sepiella japonica was cloned and characterized, and its potential function in ovarian development was investigated. The full-length cDNAs of Vg1 was 5853 base pair (bp) that encoded 748 amino acids. Sequence analysis revealed that the overall protein sequence of Vg1 shared 66% identity with that of Uroteuthis edulis. Analyses with quantitative reverse transcription polymerase chain reaction (RT-qPCR) showed that the highest expression of Vg1 occurred in the ovary. As ovary developed, the expression of Vg1 increased in both ovary and liver from oogonia phase (I) to interstitial growth phase (III), and reached to the peak value at stage III. In addition, we examined the effects of Gonadotropin-releasing hormone (GnRH) on Vg1 expression in the ovary and liver were examined. The data showed that GnRH increased mRNA expression of Vg1, indicating that exogenous GnRH initially affected Vg1 expression and then influenced ovarian maturation. This study suggests that Vg1 might be involved in ovarian development in cephalopods.","PeriodicalId":50053,"journal":{"name":"Journal of Shellfish Research","volume":"41 1","pages":"235 - 241"},"PeriodicalIF":1.3,"publicationDate":"2022-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46214061","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Averbuj, G. Herbert, V. Bökenhans, G. Bigatti, P. Penchaszadeh
ABSTRACT New marine mollusc fishery resources are constantly being incorporated to the international market. The marine gastropod Buccinanops cochlidium (Dillwyn, 1817) is a potential fisheries resource with excellent nutritional qualities. Recently, the first legislation that regulates marine gastropod fisheries based on size limits and reproductive seasonality was established in Argentina, although some biological parameters that are useful to its implementation are still needed. Fisheries managed with size limits require accurate estimates of age and growth that can be estimated through stable isotope sclerochronology. The age and growth of B. cochlidium at Playa Villarino, in north Patagonian gulf San José, Argentina was studied between 2005 and 2006. The δ18O profiles of B. cochlidium shells analyzed in this study showed a maximum age of 5 y. Opercular rings and shell growth breaks, which record age in some other gastropods, gave higher counts than the number of years shown in isotope profiles. Thus, morphological proxies are unable to correctly asses age and growth in B. cochlidium. These results are useful to support and complement the first fisheries regulation of marine gastropods recently implemented in Argentina, aimed to conserve this vulnerable and valuable resource.
{"title":"Estimating Age and Growth of the Edible Nassarid Gastropod, Buccinanops cochlidium (Dillwyn, 1817) Using Sclerochronology Records","authors":"A. Averbuj, G. Herbert, V. Bökenhans, G. Bigatti, P. Penchaszadeh","doi":"10.2983/035.041.0205","DOIUrl":"https://doi.org/10.2983/035.041.0205","url":null,"abstract":"ABSTRACT New marine mollusc fishery resources are constantly being incorporated to the international market. The marine gastropod Buccinanops cochlidium (Dillwyn, 1817) is a potential fisheries resource with excellent nutritional qualities. Recently, the first legislation that regulates marine gastropod fisheries based on size limits and reproductive seasonality was established in Argentina, although some biological parameters that are useful to its implementation are still needed. Fisheries managed with size limits require accurate estimates of age and growth that can be estimated through stable isotope sclerochronology. The age and growth of B. cochlidium at Playa Villarino, in north Patagonian gulf San José, Argentina was studied between 2005 and 2006. The δ18O profiles of B. cochlidium shells analyzed in this study showed a maximum age of 5 y. Opercular rings and shell growth breaks, which record age in some other gastropods, gave higher counts than the number of years shown in isotope profiles. Thus, morphological proxies are unable to correctly asses age and growth in B. cochlidium. These results are useful to support and complement the first fisheries regulation of marine gastropods recently implemented in Argentina, aimed to conserve this vulnerable and valuable resource.","PeriodicalId":50053,"journal":{"name":"Journal of Shellfish Research","volume":"41 1","pages":"201 - 207"},"PeriodicalIF":1.3,"publicationDate":"2022-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48540992","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-08-01Epub Date: 2022-10-24DOI: 10.2983/035.041.0206
Sarah Bodenstein, Isabelina Nahmens, Terrence R Tiersch
The genetic resources of oysters in Louisiana and the Gulf of Mexico are threatened due to high unexplained oyster mortality. Germplasm repositories are collections of cryopreserved genetic material stored alongside associated information that are used to protect genetics resources and facilitate breeding programs in agricultural industries. Therefore, there is great need for oyster repositories. Development of repositories has been slow despite research on high-throughput cryopreservation protocols because of logistical complexities. The goal of this study was to begin to address the gap between cryopreservation research and repository development in oyster aquaculture by modeling a cryopreservation protocol to understand and improve the process. The steps of a high-throughput cryopreservation protocol were defined and mapped in a process flow diagram. A simulation model was created using time study data, and key bottlenecks in the process were identified. Finally, model variations using alternate types of devices (tools or equipment) were created to address the identified bottlenecks. The model was found to accurately simulate the cryopreservation process. Parameters such as number of straws frozen per oyster, batch size, and number of operators significantly affected how the model performed and device choices produced substantial improvements. Simulation modeling has the potential to inform how cryopreservation pathways and repository systems in aquatic species should be structured and operated. There is ample opportunity for future work such as analyzing the impacts of production scale on cryopreservation processes.
{"title":"SIMULATION MODELING OF A HIGH-THROUGHPUT OYSTER CRYOPRESERVATION PATHWAY.","authors":"Sarah Bodenstein, Isabelina Nahmens, Terrence R Tiersch","doi":"10.2983/035.041.0206","DOIUrl":"10.2983/035.041.0206","url":null,"abstract":"<p><p>The genetic resources of oysters in Louisiana and the Gulf of Mexico are threatened due to high unexplained oyster mortality. Germplasm repositories are collections of cryopreserved genetic material stored alongside associated information that are used to protect genetics resources and facilitate breeding programs in agricultural industries. Therefore, there is great need for oyster repositories. Development of repositories has been slow despite research on high-throughput cryopreservation protocols because of logistical complexities. The goal of this study was to begin to address the gap between cryopreservation research and repository development in oyster aquaculture by modeling a cryopreservation protocol to understand and improve the process. The steps of a high-throughput cryopreservation protocol were defined and mapped in a process flow diagram. A simulation model was created using time study data, and key bottlenecks in the process were identified. Finally, model variations using alternate types of devices (tools or equipment) were created to address the identified bottlenecks. The model was found to accurately simulate the cryopreservation process. Parameters such as number of straws frozen per oyster, batch size, and number of operators significantly affected how the model performed and device choices produced substantial improvements. Simulation modeling has the potential to inform how cryopreservation pathways and repository systems in aquatic species should be structured and operated. There is ample opportunity for future work such as analyzing the impacts of production scale on cryopreservation processes.</p>","PeriodicalId":50053,"journal":{"name":"Journal of Shellfish Research","volume":"41 1","pages":"209-221"},"PeriodicalIF":1.3,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10824509/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42360772","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ABSTRACT Crustaceans of the family Gonodactylidae (Order Stomatopoda) are potential predators of cultured pearl oysters in ocean-culture systems, yet they have not previously been implicated in contributing to on-farm mortality of culture stock. Improved knowledge of the threat posed by stomatopods to pearl oyster survival in ocean-culture systems, as well as possible influencing factors, is necessary to determine whether stomatopod predation merits concern and for prioritizing efforts to prevent and control predator incursions. The aims of this study were, therefore, to determine if the presence of stomatopods within culture units significantly affects cultured pearl oyster survival in an ocean-culture system, and whether predator or prey size exert influencing effects. Mortality of Akoya pearl oysters (Pinctada fucata) over a 6-wk culture period ranged from zero to 33.3% among individual culture units containing a single stomatopod (Gonodactylaceus falcatus) at the study site in north Queensland, Australia. An interaction between stomatopod size and their time at liberty within culture units, as well as an interaction between stomatopod size and pearl oyster size, explained 84.1% of the variance in pearl oyster survival among culture units. Most prominently, small stomatopods (total length: 37.0 ± 0.9 mm) caused minimal mortality of culture stock (4.6% ± 1.1%), whereas large stomatopods (total length: 69.0 ± 1.1 mm) had a significantly greater impact (20.8% ± 2.1% mortality) over the 6-wk period (P < 0.05). Given the potential for a single G. falcatus to cause up to 33.3% mortality of culture stock within a culture unit, the threat from stomatopod predation during ocean culture of pearl oysters could be significant and collection of site-specific information to assess this threat is recommended.
{"title":"Stomatopod (Gonodactylaceus falcatus) Predation of the Akoya Pearl Oyster (Pinctada fucata) in Ocean Culture","authors":"A. Teitelbaum, T. Militz, P. Southgate","doi":"10.2983/035.041.0102","DOIUrl":"https://doi.org/10.2983/035.041.0102","url":null,"abstract":"ABSTRACT Crustaceans of the family Gonodactylidae (Order Stomatopoda) are potential predators of cultured pearl oysters in ocean-culture systems, yet they have not previously been implicated in contributing to on-farm mortality of culture stock. Improved knowledge of the threat posed by stomatopods to pearl oyster survival in ocean-culture systems, as well as possible influencing factors, is necessary to determine whether stomatopod predation merits concern and for prioritizing efforts to prevent and control predator incursions. The aims of this study were, therefore, to determine if the presence of stomatopods within culture units significantly affects cultured pearl oyster survival in an ocean-culture system, and whether predator or prey size exert influencing effects. Mortality of Akoya pearl oysters (Pinctada fucata) over a 6-wk culture period ranged from zero to 33.3% among individual culture units containing a single stomatopod (Gonodactylaceus falcatus) at the study site in north Queensland, Australia. An interaction between stomatopod size and their time at liberty within culture units, as well as an interaction between stomatopod size and pearl oyster size, explained 84.1% of the variance in pearl oyster survival among culture units. Most prominently, small stomatopods (total length: 37.0 ± 0.9 mm) caused minimal mortality of culture stock (4.6% ± 1.1%), whereas large stomatopods (total length: 69.0 ± 1.1 mm) had a significantly greater impact (20.8% ± 2.1% mortality) over the 6-wk period (P < 0.05). Given the potential for a single G. falcatus to cause up to 33.3% mortality of culture stock within a culture unit, the threat from stomatopod predation during ocean culture of pearl oysters could be significant and collection of site-specific information to assess this threat is recommended.","PeriodicalId":50053,"journal":{"name":"Journal of Shellfish Research","volume":"41 1","pages":"61 - 66"},"PeriodicalIF":1.3,"publicationDate":"2022-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48403410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Revilla, Gabriela Pachay-Estrada, A. Márquez, D. Rodríguez‐Pesantes, C. Lodeiros, S. Sonnenholzner
ABSTRACT Some genera of bivalve molluscs have an iconic ancestral history that predominates in the culture of a civilization through time. The Pacific thorny oyster Spondylus crassisquama is a living example of this. This study presents the description of the early life cycle until obtaining juveniles; and, for the latter, different types of substrates were evaluated. Larval culture was developed under laboratory conditions, chronologically recording the changes in larval morphology and behavior. The thorny oyster presents the first cell cleavage at 50 min postfertilization (PF). The transition between trochophore phase and the first D-veliger larvae was observed around 20–24 h PF. Above 75% of the larvae with presence of a serrate double ring showed ocular eyespot on the 16th day PF. Between the 16th and 18th days PF, the formation of the foot of the larvae was observed. The first postlarvae were observed on the 20th day with a total length of 553.0 ± 150.10 µm, distinguished by the appearance of the dissoconch. After 30 days PF, the first settled juveniles were observed with sizes of 1.6 ± 0.41 mm. Finally, the animals showed a preference for settlement on stones and concrete, and to a lesser extent on broken shells of S. crassisquama. This study shows that juvenile production is feasible under laboratory conditions; however, this requires more research to optimize the nursery process.
{"title":"Early Life Cycle of the Pacific Thorny Oyster Spondylus crassisquama (Lamark, 1819)","authors":"J. Revilla, Gabriela Pachay-Estrada, A. Márquez, D. Rodríguez‐Pesantes, C. Lodeiros, S. Sonnenholzner","doi":"10.2983/035.041.0106","DOIUrl":"https://doi.org/10.2983/035.041.0106","url":null,"abstract":"ABSTRACT Some genera of bivalve molluscs have an iconic ancestral history that predominates in the culture of a civilization through time. The Pacific thorny oyster Spondylus crassisquama is a living example of this. This study presents the description of the early life cycle until obtaining juveniles; and, for the latter, different types of substrates were evaluated. Larval culture was developed under laboratory conditions, chronologically recording the changes in larval morphology and behavior. The thorny oyster presents the first cell cleavage at 50 min postfertilization (PF). The transition between trochophore phase and the first D-veliger larvae was observed around 20–24 h PF. Above 75% of the larvae with presence of a serrate double ring showed ocular eyespot on the 16th day PF. Between the 16th and 18th days PF, the formation of the foot of the larvae was observed. The first postlarvae were observed on the 20th day with a total length of 553.0 ± 150.10 µm, distinguished by the appearance of the dissoconch. After 30 days PF, the first settled juveniles were observed with sizes of 1.6 ± 0.41 mm. Finally, the animals showed a preference for settlement on stones and concrete, and to a lesser extent on broken shells of S. crassisquama. This study shows that juvenile production is feasible under laboratory conditions; however, this requires more research to optimize the nursery process.","PeriodicalId":50053,"journal":{"name":"Journal of Shellfish Research","volume":"41 1","pages":"95 - 100"},"PeriodicalIF":1.3,"publicationDate":"2022-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44404827","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Tanu, A. Barman, Mohammad Ferdous Siddque, Sonia Sku, Md. Nazmul Hossen, P. Southgate, Y. Mahmud
ABSTRACT Pearls are gems produced by biological processes within the living tissues of molluscs. Image pearls are a form of blister pearl that portray a design or image such as a bird, fish, flower, goddess, etc. To achieve this, a paraffin wax mold is inserted between the shell and the mantle of a freshwater mussel and subsequent nacre coverage produces an image pearl after an appropriate culture period for the mussel. The optimum culture period has not yet been determined to maximize the quality of image pearls produced in Bangladesh, and this knowledge gap was addressed in this study. Image pearl production using the freshwater mussel Lamellidens marginalis was conducted over three culture periods (T 1 = 7 mo, T 2 = 9 mo, and T 3 = 11 mo). A total of 3,150 mussels were implanted with 2.5 × 1.5 cm2 paraffin wax molds, with 1,050 mussels allocated to each treatment, which had five replicates. Survival and pearl production rate of mussels were negatively correlated with culture period. Survival and pearl production rate were 14.7%, 12.3%, and 11.9% for mussels cultured for 7, 9, and 11 mo, respectively. The thicknesses of the nacre making up the image pearl and pearl luster were both improved with longer culture periods. The highest quality pearls with a mean nacre thickness of 0.71 mm were produced after 11 mo. Pearls produced after 11 mo also had the highest luster (40.05 lux) compared with pearls cultured for 7 mo (12.85 lux) or 9 mo (30.2 lux). There were statistically significant differences at the P < 0.05 level in survival rate F (2, 12) = 9.40, P = 0.004 and nacre layer thickness F (2, 12) = 13.30, P = 0.001 between T 1 and T 3. The results indicated that image pearls with high luster and improved quality are produced after longer culture durations and confirms the influence of culture period on image pearl production and quality. Further research is required to improve image pearl production methods and pearl yield.
{"title":"Impact of Culture Period on Quality of Image Pearls Produced by the Freshwater Mussel, Lamellidens marginalis, in Bangladesh","authors":"M. Tanu, A. Barman, Mohammad Ferdous Siddque, Sonia Sku, Md. Nazmul Hossen, P. Southgate, Y. Mahmud","doi":"10.2983/035.041.0104","DOIUrl":"https://doi.org/10.2983/035.041.0104","url":null,"abstract":"ABSTRACT Pearls are gems produced by biological processes within the living tissues of molluscs. Image pearls are a form of blister pearl that portray a design or image such as a bird, fish, flower, goddess, etc. To achieve this, a paraffin wax mold is inserted between the shell and the mantle of a freshwater mussel and subsequent nacre coverage produces an image pearl after an appropriate culture period for the mussel. The optimum culture period has not yet been determined to maximize the quality of image pearls produced in Bangladesh, and this knowledge gap was addressed in this study. Image pearl production using the freshwater mussel Lamellidens marginalis was conducted over three culture periods (T 1 = 7 mo, T 2 = 9 mo, and T 3 = 11 mo). A total of 3,150 mussels were implanted with 2.5 × 1.5 cm2 paraffin wax molds, with 1,050 mussels allocated to each treatment, which had five replicates. Survival and pearl production rate of mussels were negatively correlated with culture period. Survival and pearl production rate were 14.7%, 12.3%, and 11.9% for mussels cultured for 7, 9, and 11 mo, respectively. The thicknesses of the nacre making up the image pearl and pearl luster were both improved with longer culture periods. The highest quality pearls with a mean nacre thickness of 0.71 mm were produced after 11 mo. Pearls produced after 11 mo also had the highest luster (40.05 lux) compared with pearls cultured for 7 mo (12.85 lux) or 9 mo (30.2 lux). There were statistically significant differences at the P < 0.05 level in survival rate F (2, 12) = 9.40, P = 0.004 and nacre layer thickness F (2, 12) = 13.30, P = 0.001 between T 1 and T 3. The results indicated that image pearls with high luster and improved quality are produced after longer culture durations and confirms the influence of culture period on image pearl production and quality. Further research is required to improve image pearl production methods and pearl yield.","PeriodicalId":50053,"journal":{"name":"Journal of Shellfish Research","volume":"41 1","pages":"75 - 83"},"PeriodicalIF":1.3,"publicationDate":"2022-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45743002","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lacey N. Dennis-Cornelius, Michael B. Williams, John A. Dawson, Mickie L. Powell, S. Watts
ABSTRACT Sea urchins are important inhabitants of many marine ecosystems. They are also an economic resource for many international fisheries and are an important animal model in developmental biology. Sea urchins ingest a variety of plant and animal matter, form a digesta pellet, and produce an egesta (fecal) pellet that contributes to benthic food webs. The size and morphology of fecal pellets produced by various size classes of the sea urchin Lytechinus variegatus fed a variety of natural, vegetable-based, or formulated diets were characterized in terms of two-dimensional area, length (long diameter), width (short diameter), and circularity, as well as by ultrastructure analysis using transmission electron microscopy (TEM). Sea urchins fed natural and vegetable-based ingredients produced a wide variety of irregularly shaped egesta that were loosely surrounded by mucus, whereas urchins fed a formulated diet produced highly circular egesta surrounded by a uniform multilayered mucus coat. Larger urchins (62 ± 3.1 g wet weight) consuming a formulated diet produced egesta that were larger in size than smaller adult (26.5 ± 2.7 g) or juvenile urchins (3.6 ± 0.4 g), with egesta length of 0.93 ± 0.06, 0.75 ± 0.05, and 0.61 ± 0.01 mm, respectively (mean ± 95% confidence interval [CI]; P < 0.001). Ultrastructural analysis of the egesta using TEM image analysis software from urchins consuming formulated diets indicated that pellets contained extensive bacterial communities, ranging from 31% to 69% of the total cross-sectional area of the pellet, with dense communities located near the surface of the pellet (9.51 × 108 cells/cm2). Qualitative examination of the egesta TEM suggested the presence of a diverse bacterial community. Following egestion, these microbial communities are suggested to have an important role in natural food webs, with potential value for integrated multitrophic aquaculture systems.
{"title":"Effect of Diet and Body Size on Fecal Pellet Morphology in the Sea Urchin Lytechinus variegatus","authors":"Lacey N. Dennis-Cornelius, Michael B. Williams, John A. Dawson, Mickie L. Powell, S. Watts","doi":"10.2983/035.041.0111","DOIUrl":"https://doi.org/10.2983/035.041.0111","url":null,"abstract":"ABSTRACT Sea urchins are important inhabitants of many marine ecosystems. They are also an economic resource for many international fisheries and are an important animal model in developmental biology. Sea urchins ingest a variety of plant and animal matter, form a digesta pellet, and produce an egesta (fecal) pellet that contributes to benthic food webs. The size and morphology of fecal pellets produced by various size classes of the sea urchin Lytechinus variegatus fed a variety of natural, vegetable-based, or formulated diets were characterized in terms of two-dimensional area, length (long diameter), width (short diameter), and circularity, as well as by ultrastructure analysis using transmission electron microscopy (TEM). Sea urchins fed natural and vegetable-based ingredients produced a wide variety of irregularly shaped egesta that were loosely surrounded by mucus, whereas urchins fed a formulated diet produced highly circular egesta surrounded by a uniform multilayered mucus coat. Larger urchins (62 ± 3.1 g wet weight) consuming a formulated diet produced egesta that were larger in size than smaller adult (26.5 ± 2.7 g) or juvenile urchins (3.6 ± 0.4 g), with egesta length of 0.93 ± 0.06, 0.75 ± 0.05, and 0.61 ± 0.01 mm, respectively (mean ± 95% confidence interval [CI]; P < 0.001). Ultrastructural analysis of the egesta using TEM image analysis software from urchins consuming formulated diets indicated that pellets contained extensive bacterial communities, ranging from 31% to 69% of the total cross-sectional area of the pellet, with dense communities located near the surface of the pellet (9.51 × 108 cells/cm2). Qualitative examination of the egesta TEM suggested the presence of a diverse bacterial community. Following egestion, these microbial communities are suggested to have an important role in natural food webs, with potential value for integrated multitrophic aquaculture systems.","PeriodicalId":50053,"journal":{"name":"Journal of Shellfish Research","volume":"41 1","pages":"135 - 144"},"PeriodicalIF":1.3,"publicationDate":"2022-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47044152","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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