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1.
Jun Iguchi Yasuharu Takashima Atsushi Namikoshi Yumiko Yamashita Michiaki Yamashita 《Fisheries Science》2013,79(6):977-982
The correlations among the contents of trace elements in the shells of short-neck clams collected from Japan, China, and the Republic of Korea were examined. Origin-specific elemental content patterns were seen in clams originating from Japan, China, and the Republic of Korea. The crushed shells were decomposed with nitric acid–hydrogen peroxide, and the concentrations of ten elements (Li, V, Mn, Co, As, Rb, Mo, Ba, Pb, and U) in the shells were measured by inductively coupled plasma mass spectrometry. Some of the metal concentrations in the samples displayed clear geographical trends. The average concentration of Pb in Japanese clam shells was one-half to one-quarter that seen in Chinese or Korean clams. Average concentrations of As, Rb, and Ba in shells of Japanese origin were one-half those observed in Chinese or Korean clams. Linear discriminant analysis was applied to these analytical data, and four discriminant models were constructed. These discriminant models were able to distinguish the geographic origins of short-neck clams with 80.0–100 % accuracy. In particular, clams of Japanese origin were classified correctly ≥90 % of the time. Therefore, the trace elemental analysis of a short-neck clam shell is useful for identifying the country of origin of the clam. 相似文献
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Extreme ocean acidification reduces the susceptibility of eastern oyster shells to a polydorid parasite 
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下载免费PDF全文 J C Clements D Bourque J McLaughlin M Stephenson L A Comeau 《Journal of fish diseases》2017,40(11):1573-1585
Ocean acidification poses a threat to marine organisms. While the physiological and behavioural effects of ocean acidification have received much attention, the effects of acidification on the susceptibility of farmed shellfish to parasitic infections are poorly understood. Here we describe the effects of moderate (pH 7.5) and extreme (pH 7.0) ocean acidification on the susceptibility of Crassostrea virginica shells to infection by a parasitic polydorid, Polydora websteri. Under laboratory conditions, shells were exposed to three pH treatments (7.0, 7.5 and 8.0) for 3‐ and 5‐week periods. Treated shells were subsequently transferred to an oyster aquaculture site (which had recently reported an outbreak of P. websteri) for 50 days to test for effects of pH and exposure time on P. websteri recruitment to oyster shells. Results indicated that pH and exposure time did not affect the length, width or weight of the shells. Interestingly, P. websteri counts were significantly lower under extreme (pH 7.0; ~50% reduction), but not moderate (pH 7.5; ~20% reduction) acidification levels; exposure time had no effect. This study suggests that extreme levels – but not current and projected near‐future levels – of acidification (?pH ~1 unit) can reduce the susceptibility of eastern oyster shells to P. websteri infections. 相似文献
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Influence of fouling on the growth and survival of the tropical scallop, Euvola (Pecten) ziczac (L. 1758) in suspended culture 总被引：3，自引：0，他引：3
To examine the impact of fouling organisms on the growth and survival of the scallop Euvola ziczac L., we maintained 31-34-mm juveniles in pearl nets at 8 m in depth at Turpialito, Golfo de Cariaco, Venezuela. The experiment ran for a 67-d period under four conditions: (1) shells and nets cleaned; (2) shells not cleaned and nets cleaned; (3) shells cleaned and nets not cleaned; and (4) shells and nets not cleaned. The growth of the scallop was least when fouling developed on both the pearl nets and scallop shells. The rate of growth of the shell (height and mass) was strongly affected by organisms colonizing the pearl nets and only weakly affected by organisms colonizing the shells. Fouling organisms on the shells only slightly affected rates of increase of tissue mass, but probably accounted for increased mortality. In developing commercial culture of E. ziczac, strategies need to be developed to limit the adverse effects of fouling on yield. 相似文献
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本研究在抗压强度为C25的普通混凝土配合比的基础上,采用粗、细扇贝壳对混凝土中的天然骨料部分替代,并对扇贝壳混凝土配合比进行了研究,比较了粗、细扇贝壳替代天然骨料混凝土的工作性能和基本力学性能,并根据山东省2016~2020年的投礁计划,对利用扇贝壳替换人工鱼礁混凝土中天然骨料的固碳潜能及可清理的废弃扇贝壳堆积面积进行估算。结果显示,随着扇贝壳替换天然骨料比例的增加,混凝土的塌落度呈降低趋势。粗扇贝壳替换天然粗骨料混凝土较细扇贝壳替换天然细骨料混凝土的塌落度降幅大;粗扇贝壳替代混凝土中的天然石时,扇贝壳混凝土的抗压性能与基准混凝土基本接近,粗扇贝壳的最佳替代率为40%,28 d抗压强度较基准混凝土提高了7.3%。用细扇贝壳替代混凝土中的天然砂时,可使混凝土的抗压性能较基准混凝土提高幅度较大,最佳替代率为60%,28 d抗压强度较基准混凝土提高了33.5%;以细扇贝壳替换混凝土天然细骨料替换率为50%~70%估算,山东省2016~2020年计划新建的2043万空方人工鱼礁均用此种混凝土制作,可实现礁体固碳量27.54~38.56万t,可减少废弃贝壳陆地堆积面积5.89~8.24 km2,具有很高的生态潜能。 相似文献
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贝壳的结构与应用的研究现状 总被引：1，自引：0，他引：1
我国的贝壳资源十分丰富,但囿于技术等问题,利用率一直较为低下。为此,对贝壳的成分、结构进行了介绍,并由此引申出其相关特性,同时,综合相关研究,列举了贝壳在作为吸附剂、杀菌剂、催化剂和用于功能材料等方面的应用,对贝壳的资源化利用提出建议。 相似文献
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Clyde L. MacKenzie 《Aquaculture (Amsterdam, Netherlands)》1977,10(1):45-51
A single application of quicklime (calcium oxide), spread at a rate of 6.75 metric tons/ha, was used to prepare dormant oyster setting beds for spat production. Of 2 000 ha in Long Island Sound, Connecticut, U.S.A., 1200 ha had sufficient shells to cover at least 75% of the bottom. However, these shells had a continuous fouling organism layer that would prevent significant oyster setting. Many beds had predator populations of sea stars (Asterias forbesi) and oyster drills (Urosalpinx cinerea and Eupleura caudata). Quicklime cleans the shells by killing fouling organisms, and also controls sea stars and embryonic oyster drills.When the supply of clean shells for annual spreading on the setting beds is limited, use of the quicklime method prepares greater quantities of shells for possible oyster set. 相似文献
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为研究藤壶壳作为生物滤料应用于对虾养殖尾水处理的可行性,通过比较陶瓷环组、聚乙烯(PE)组、藤壶壳组和藤壶壳+PE组4个不同滤料组合的生物挂膜效果,初步评价藤壶壳作为生物滤料的应用价值;通过设定藤壶壳的不同填充率(滤料体积∶尾水体积),研究填充率对对虾塘养殖尾水处理效果的影响。结果显示:藤壶壳组挂膜成功时间较早,水处理效果好;藤壶壳不同填充率对水处理中悬浮物、氨氮(NH_4~+-N)、亚硝酸盐氮(NO_2~--N)的处理效果有显著影响,A、B、C、D各组悬浮物在6 h时的去除率分别达(68.7±4.3)%、(74.5±7.0)%、(80.9±4.2)%和(82.1±3.8)%,其中B、C、D组去除率显著高于A组(P0.05);4组的氨氮最终去除率都在92.1%以上,以0.1 mg/L为基准,A组氨氮降至此质量浓度以下需要时间5 d,B、C组4 d,D组3 d,降解速率为D组C组B组A组;4组的亚硝酸盐氮最终去除率都在98.0%以上,以0.1 mg/L为基准,A组的亚硝酸盐氮降至此质量浓度以下需要时间为6 d,B、C、D组需要5 d,降解速率为D组C组B组A组。研究表明:藤虎壳作为生物滤料应用于对虾养殖尾水处理,效果良好,且随着填充率的增大,处理效率增强;但考虑到经济成本和应用实际,建议藤壶壳填充率为2∶9。 相似文献
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Modifications of great scallop (Pecten moximus) shells have been noticed in many sites of scallop fisheries in Brittany, especially in shallow waters. These calcification abnormalities are linked to the appearance of a brown colouration of the internal calcified shell layer, due to the presence of a eumelanin associated with the insoluble organic matrix of the biocrystals. The appearance of this pigment generates many disturbances of the calcified foliated microstructure of the scallop internal shell layer. The mantle structure is not modified in brown shells as compared with white ones. No pathogenic signs such as hyperplasia or haemocytic infiltration have been observed. According to this observation, we hypothesize that the brown colour phenomenon is more a result of environmental disturbance rather than a symptom of a pathogenic disease.The colour abnormalities of the internal shell layer can be detected by a spectral analysis of its reflectance before it can be detected with the naked eye. This method, correlated to microstructural observations, gives a rapid and precise analysis of the appearance of the pigmentation on adult or juvenile scallops. It may be a useful method for the evaluation of the influence of environmental parameters, for example, on calcification and its abnormalities. 相似文献
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Identification of a microsatellite marker that is completely linked to shell colour in small abalone,Haliotis diversicolor 下载免费PDF全文
下载免费PDF全文 A novel orange shell colour has been discovered in small abalone, Haliotis diversicolor (Reeve, 1846). To facilitate and accelerate a selective breeding programme for orange shell colour, a microsatellite marker that was completely linked to the shell colour gene was identified using a selective DNA pool approach and was verified in 448 individuals. Two DNA pools were constructed by pooling equal amounts of genomic DNA from 74 individuals with dark‐brown shells and 87 individuals with orange shells. Approximately 12 of 308 microsatellite markers that were linked to the shell colour gene were isolated using the selective DNA pooling method. After verification in 32 individuals with dark shells and 32 individuals with orange shells, only the Hdi3‐119 locus remained tightly linked to the shell colour gene. Finally, four families were used to verify the accuracy of the Hdi3‐119 locus. All of the individuals with orange shells in the four families harboured a unique 381‐bp allele in marker Hdi3‐119. This marker could be used for selective breeding of orange small abalone. 相似文献
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Jes Jessen Rasmussen Liselotte Wesley Andersen Trine Just Johnsen Jens Thaulow Marc Anglès d'Auriac Søren Nøhr Thomsen Martin Hesselsøe 《水产资源保护:海洋与淡水生态系统》2021,31(9):2506-2514
- Environmental DNA (eDNA) from water samples is increasingly used to detect the presence and distribution of species in aquatic ecosystems. However, before implementing eDNA in monitoring programmes, various species-specific sampling or analytical issues remain to be resolved in order to minimize frequencies of false-positive and -negative results. For example, empty shells from freshwater pearl mussels (Margaritifera margaritifera) contain extractable DNA (chemical extraction from ground-up shells) suggesting a risk of false-positive samples at stream sites with extinct populations but with empty shell material remaining.
- The aim of this study was to investigate whether empty and naturally degrading shells from M. margaritifera can cause false-positive eDNA signals in water samples.
- Water samples were collected from outdoor stream channels (in Lemming, Denmark) with living freshwater pearl mussels or empty shell material (density ~10 individuals m−2) during a 3-week experimental period. Living freshwater pearl mussels were collected from Hemgravs stream in Sweden and transported to Denmark according to permissions granted by the Swedish and Danish authorities.
- All water samples from stream channels containing empty shells were negative for eDNA indicating that eDNA traces in stream water are most likely to originate from living individuals located upstream of the sampling site. Water samples collected from stream channels containing living individuals of M. margaritifera were consistently positive for eDNA except for one sample (interpreted as a false negative).
- The study shows that positive eDNA signals for freshwater pearl mussels most likely reflect the presence of living individuals. Consequently, we suggest that eDNA should be used to locate remaining population fragments of M. margaritifera in deep and turbulent streams, providing a platform for faster and more efficient decision making when launching investigative and mitigation initiatives.
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Saleh Hasan Omar Bahasan Mohammad Abdulaziz Ba-akdah 《Journal Of Aquatic Food Product Technology》2017,26(4):390-405
Traditionally, chitin is extracted from crustacean shells using chemical methods involving the use of strong acids and alkali. In this study, chitin was extracted from the shrimp shell waste using microbes isolated from the fermented milk and bread. The chitin yield from the shells of Fenneropenaeus semisulcatus was 14.054% and 16.062%, respectively, for shell:bacterial broth ratios of 1:15 and 1:25; whereas, the yield of chitin from the shells of Fenneropenaeus indicus was 14.93% and 13.871%, respectively, at 1:15 and 1:25 broth ratios. The Fourier transform infrared spectra obtained from the chitin samples showed characteristic chitin peaks in both shell to bacterial broth ratio. The X-ray diffraction analysis revealed peaks between 10–15 and 25–30 degrees in the chitin recovered from both species, though some variations between species were observed. In conclusion, results of the present study indicate that application of microorganisms for the extraction of chitin from the shrimp shell waste could be an alternative for the traditional chemical methods. 相似文献
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Ryutei Inui Norio Onikura Motoyoshi Kawagishi Masaya Nakatani Yuta Tomiyama Shin Oikawa 《Fisheries Science》2010,76(1):83-91
We examined the spawning sites of several gobiid fishes in the subtidal zone of a small temperate estuary and determined the relationship of the nest abundance of each species with several environmental conditions, including water temperature, salinity, median particle size, proportion of silt and clay, current width, maximum water depth, distance from each site to the river mouth, and density of objects (boulders, cobbles, empty oyster shells, and empty clam shells) in the water. During this study, we found 115 nests belonging to the following six species: Favonigobius gymnauchen, Tridentiger obscurus, Leucopsarion petersii, Acanthogobius lactipes, Rhinogobius giurinus, and Tridentiger trigonocephalus. Stepwise multiple regression analysis, which was used to determine the best model for the nest abundance of all species, revealed that the nest abundance of each species clearly increased with an increase in the density of spawning substrates, such as cobbles and bivalve shells. These results show that the density of spawning substrates is a crucial factor affecting the selection of spawning habitats by each species. 相似文献
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Zhi Yong Ju Cecilia Viljoen Peter Hutchinson Justin Reinicke F David Horgen Luke Howard Cheng‐Sheng Lee 《Aquaculture Research》2016,47(12):4004-4014
This study investigated the effects of natural and artificial diets on growth performance and shell pigmentation of cultured abalone. A 7‐month feeding trial was conducted on 12 000 Pacific abalones (Haliotis discus hannai) with four diets including two extruder‐processed test diets (with & without addition of oleopaprika carotenoids), Pacific dulse (Palmaria mollis) and a combination of Pacific dulse and a test diet. The results showed that the two test diets resulted in higher survival of abalone, but with a lower growth rates when compared with Pacific dulse alone (P < 0.05). The combination diet achieved the highest survival and growth rates. The Pacific dulse resulted in abalone with dark‐brown shells, which are preferred by Asian markets. The test diets led to 52% and 55% of the animals with pink coloured shells and the supplementation of oleopaprika did not affect shell pigmentation. The aqueous acidic extracts from both dark‐brown and pink shells showed blue colour; HPLC‐MS chromatography revealed that the pigments in the extracts were consistent with a biliverdin and a cysteine‐biliverdin. These results are valuable for the development of abalone feed and the control of abalone shell colouration. 相似文献
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Masahiko Awaji Toshie Matsumoto Daisuke Ojima Shunsuke Inoue Michio Suzuki Masaei Kanematsu 《Fisheries Science》2018,84(3):535-551
For recovery of the declining population of pen shells in the wild, the production of pen shell juveniles for transplantation or aquaculture is underway in Japan. For more stable juvenile production, artificial fertilization methods for pen shells are needed, but methods to induce oocyte maturation (meiosis resumption) used in other bivalves, which make oocytes fertilizable, were ineffective for pen shells. Here, we report evidence showing that retinoic acid (RA) has strong activity in inducing oocyte maturation and activating sperm motility in pen shells. Treatment of fully developed oocytes with 1.0 μM all-trans-RA (at-RA) induced germinal vesicle breakdown, a typical morphological sign of oocyte maturation, but 1.0 μM at-retinol and at-retinal, 2 mM ammonia, and 1.0 μM serotonin were ineffective. Treatment with at-RA for 30 min was sufficient for oocyte maturation and was more potent than its isomers, 9-cis- and 13-cis-RA. Parallel results were obtained for sperm motility activation. Oocyte responsiveness to at-RA increased during the final stage of ovary development. Artificial fertilization was successful only with the oocytes treated with at-RA, and fertilized eggs developed to D-shaped (veliger) larvae without apparent morphological abnormalities. These results indicate the possible application of RA for the artificial fertilization of pen shells. 相似文献
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Abstract. A survey was carried out in Karimun Jawa, a group of islands off the north coast of Central Java, in order (1) to investigate the environmental effect of the collection of giant clam shells used for floor tile manufacture, (2) to investigate the distribution and abundance of living populations of Tridacna spp. and to determine whether the larger species of giant clams are still to be found in the area and (3) to determine the suitability of this area for reseeding of giant clam species for mariculture and/or fishery development. Results showed that the collection of T. gigas shells for the manufacture of floor tiles did not have the same damaging effect on the coral environment as reported elsewhere. They also showed that populations of T, crocea, T. maxima and T. squamosa were still thriving while T. gigas, H. hippopits and T. derusa were extremely rare if not actually extinct, one individual alone of T. derasa being found. The potential for reintroduction of these latter species and for the encouragement of mariculture or fishery development into these islands seems great and is strongly advocated. 相似文献
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Claire N. Greenwell Neil R. Loneragan Ryan Admiraal James R. Tweedley Mark Wall 《Fisheries Management and Ecology》2019,26(2):108-118
This study examined the occurrence of octopus across an abalone, Haliotis laevigata, Donovan, sea ranch in south‐western Australia, to understand how octopus may be impacting abalone production. Commercial divers removed 654 octopus and 17,666 empty abalone shells during regular, 2 to 4‐weekly surveys over 27 months. A negative binomial generalised linear model estimated a 78% increase in empty shells per artificial abalone habitat per day, when octopuses were present, after adjusting for location and season. Of the 408 shells examined for evidence of predation, 19% had a small, slightly ovoid hole consistent with those made by octopus. The mean (± 1 SE) length of shells with boreholes (70.3 ± 2.2 mm) was significantly longer than those without (59.8 ± 0.5 mm), and boreholes were concentrated over the adductor, respiratory organs and heart. This study provides important insights into the adaptable feeding regimes of octopus and their potential to impose strong top‐down controls on sea ranching operations. 相似文献
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The protein requirements for optimal growth and health of juvenile New Zealand black‐footed abalone (Haliotis iris) under different water temperatures were investigated. Six diets with different crude protein amounts (0, 10, 20, 30, 40 and 45%) and two temperature regimes (13–21 and 8–16 °C) were used to culture juvenile abalone over a 4‐month period. Growth (shell lengths and animal weights) and health (survival, activity and mucous production) parameters were recorded for animals within all protein and temperature combinations. Proximate analyses and amino acid profiles were also performed on the diets, soft bodies (including gonad), and shells to evaluate the overall nutrient contents (diet and animal) and requirements (animal). The results indicate that the protein requirements for juvenile H. iris are higher when the environmental temperatures are low. Thus, increasing the dietary protein level results in better growth [i.e. increase in soft body (including gonad) crude protein and mean protein gain] and health (i.e. more goblet cells and thicker epithelial layers). Results from amino acid profiles in abalone soft bodies (including gonad) and shells show that these parameters did not change considerably with different dietary protein levels, but temperature did affect the concentration of several amino acids in both soft bodies (including gonad) and shells. 相似文献