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Artykuły w czasopismach na temat "Mud crab"
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Samidjan, Istiyanto, Diana Rachmawati i Putut Har Riyadi. "Development of Polyculture Engineering Technology on Milkfish and Mud Crab Farming". Pertanika Journal of Tropical Agricultural Science 45, nr 2 (22.03.2022): 377–89. http://dx.doi.org/10.47836/pjtas.45.2.03.
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The current study aimed to evaluate the role of polyculture engineering technology on milkfish and mud crab farming and observe the growth and survivability of different milkfish and mud crab combinations. The study used milkfish, which was received artificial feed containing 35 % protein content enriched with vitamin E (3%/biomass/day). The study used completely randomized design with 4 treatments (n = 3): T1 = 5 milkfish + 5 mud crab, T2 = 10 milkfish + 5 mud crab, T3 = 5 milkfish + 10 mud crab, T4 = 10 milkfish + 10 mud crab. The following parameters were measured: absolute weight growth, survival rate, feed conversion rate (FCR), and water quality. The difference in the density of milkfish and mud crabs significantly affected (p < 0.05) the growth and survivability of milkfish and mud crabs. The polyculture cultivation system exhibited a significant increase in absolute weight growth of milkfish and mud crabs, which is the highest increase found in T4 treatment (187.85 g ± 0.9 g and 60.65 g ± 0.95 g, respectively). Meanwhile, the survival rate of milkfish and mud crab was 95% ± 0.3% and 95% ± 2.3%, respectively, followed by a lower FCR at T4 (1.54 ± 0.10). The water quality remained good for fish and mud crabs to survive. Milkfish and mud crab polyculture greatly affect the abundance of phytoplankton, demonstrating good community structure.
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Schweiss, Virginia R., i Chet F. Rakocinski. "Destabilizing effects on a classic tri-trophic oyster-reef cascade". PLOS ONE 15, nr 12 (15.12.2020): e0242965. http://dx.doi.org/10.1371/journal.pone.0242965.
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How interactions among multiple predators affect the stability of trophic cascades is a topic of special ecological interest. To examine factors affecting the stability of the classic tri-trophic oyster reef cascade within a different context, configurations of three predators, including the Gulf toadfish, Gulf stone crab, and oystershell mud crab, were manipulated together with either oyster shell or limestone gravel substrate within a multiple predator effects (MPE) experiment. Additionally, a complimentary set of trait-mediated-indirect interaction (TMII) experiments examined the inhibition of oyster consumption relative to mud-crab size and top predator identity in the absence of other cues and factors. The classic tri-trophic cascade formed by the toadfish-mud crab-oyster configuration was potentially weakened by several interactions within the MPE experiment. Consumption of oysters and mud crabs by the intraguild stone crab was undeterred by the presence of toadfish. Although mud crab feeding was inhibited in the presence of both toadfish and stone crabs, estimated non-consumptive effects (NCEs) were weaker for stone crabs in the MPE experiment. Consequently, the total effect was destabilizing when all three predator species were together. Inhibition of mud crab feeding was inversely related to direct predation on mud crabs within the MPE experiment. Complimentary TMII experiments revealed greater inhibition of mud crab feeding in response to stone crabs under sparse conditions. TMII experiments also implied that inhibition of mud crab feeding could have largely accounted for NCEs relative to oysters within the MPE experiment, as opposed to interference by other mud crabs or top predators. An inverse relationship between mud crab size and NCE strength in the TMII experiment disclosed another potentially destabilizing influence on the tri-trophic-cascade. Finally, although habitat complexity generally dampened the consumption of oysters across MPE treatments, complex habitat promoted mud crab feeding in the presence of toadfish alone. This study underscores how ecological interactions can mediate trophic cascades and provides some additional insights into the trophic dynamics of oyster reefs for further testing under natural conditions.
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Wan Yusof, Wan Roslina, Fasihuddin Badruddin Ahmad i Mummedy Swamy. "A Brief Review on the Antioxidants and Antimicrobial Peptides Revealed in Mud Crabs from the Genus of Scylla". Journal of Marine Biology 2017 (2017): 1–7. http://dx.doi.org/10.1155/2017/1850928.
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Mud crab from the genus Scylla is also known as mangrove crab, which has been well-accepted as a good source of protein. Recently, the antioxidant properties present in mud crabs have been reported to have a part in the protection of cells against free radicals. Meanwhile, numerous antimicrobial peptides from mud crabs have managed to be characterized through the display of antimicrobial activities against Gram-positive and Gram-negative bacteria. Hence, this paper is an effort to collect recent literatures on antioxidant and antimicrobial properties in every part of mud crabs which include muscle tissue, hemolymph, and crab shell. Moreover, the effort to understand the biological properties of mud crabs is important to enhance its production in aquaculture industry. Therefore, this review hoped to attract the attention of natural product researchers to focus on the potential therapeutic applications of mud crabs.
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Sayeed, Zubayer, Hiroaki Sugino, Yutaro Sakai i Nobuyuki Yagi. "Consumer Preferences and Willingness to Pay for Mud Crabs in Southeast Asian Countries: A Discrete Choice Experiment". Foods 10, nr 11 (19.11.2021): 2873. http://dx.doi.org/10.3390/foods10112873.
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The mud crab (Scylla serrata) is an economically important species found in the mangroves and estuaries of tropical countries and is a popular seafood product in the coastal areas of Southeast Asian markets. The aim of this study is to identify factors affecting consumer preference of mud crabs, and to understand consumers’ willingness to pay (WTP) for these factors in a Singapore market where imported mud crabs from other Asian countries are sold. The results showed that the country of origin matters to participants, affecting purchasing decisions, and consumers were willing to pay approximately 16.48 SGD (11.49 USD, the average price of four shops: 35.55 USD/kg for one mud crab) more if the mud crabs were from Sri Lanka if compared with Indonesian or Cambodian mud crabs. Moreover, consumers were willing to pay 25.08 SGD (17.48 USD) more if the mud crabs were alive and 13.40 SGD (9.34 USD) less if the mud crabs were frozen compared with fresh, but not alive, mud crabs. Furthermore, consumers’ preference in mud crab was associated with the consumers’ religion. Some groups of consumers preferred female mud crabs with eggs over male mud crabs, while other groups preferred male crabs. The results identified diverse consumer preference of mud crabs and, therefore, could provide new insights that are useful for sustainable consumption of mud crabs in the region.
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Iromo, Heppi, Zainuddin i dan Syawaluddin. "Study of Mud Crab Species (Scylla Spp.) In Brackish Waters North Kalimantan Province". IOP Conference Series: Earth and Environmental Science 1083, nr 1 (1.09.2022): 012049. http://dx.doi.org/10.1088/1755-1315/1083/1/012049.
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Abstract Despite the importance of the mud crab species (genus Scylla) both in the development of crab culture in brackish waters, knowledge of mud crab species diversity for sustainable management throughout the coastal areas of North Kalimantan Province is still unclear. Therefore, this study was conducted to describe. The diversity of mud crabs in these waters is based on observations of crab morphology collected from five small islands in the coastal area of North Kalimantan. This study aims to identify the mud crab (Scylla spp.) species that live in the waters of North Kalimantan. It is hoped that this research can provide basic information about the types of mangrove crabs (Scylla spp.) that exist and live in the waters of North Kalimantan so that they can be used as a reference in the development and conservation of mud crab resources in North Kalimantan. This study uses a descriptive method to describe and describe the existing conditions in the field. Sampling was taken at random with different weights of 5 crabs/location at each high tide and carried out 2 times in every month. Sampling locations were carried out on several islands with many traditional ponds around the waters of North Kalimantan. The results of the study from Abstract100 samples of mud crabs showed that the types of mangrove crabs found in the waters of North Kalimantan were two species, namely Scylla serrata and Scylla tranquebarica.
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Purna, Selobing, Misbakhul Munir i Dian Sari Maisaroh. "Study of Ectoparasite Prevalence and Intensity on Mud Crab (Scylla serrata) in Mangrove Area of Wonorejo Surabaya". Journal of Marine Resources and Coastal Management 2, nr 1 (16.02.2021): 1–6. http://dx.doi.org/10.29080/mrcm.v2i1.1121.
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This study aims to know various types, prevalence, and intensity of ectoparasite on mud crab (Scylla serrata) in Mangrove Forest Wonorejo, Surabaya. This study used survey method with random sampling to collect the data. This study was conducted in November 2020. Ectoparasite in this study collected by smear method. In-situ water quality measurement were applied in this study. Mud crab (Scylla serrata) in this study was obtained from local fisherman that consist of 30 crabs. There are 3 types of ectoparasite was infected mud crab there are Octolasmis sp. (208 ind), Zoothamnium sp. (93 ind), dan Epistylis sp. (116 ind). Those ectoparasite was found in mud crabs gills. The highest prevalence was Octolasmis sp. (70%), Epistylis sp. (30%), Zoothamnium sp. (23%). The highest intensity was Zoothamnium sp (13,29 ind/crab), Epistylis sp. (12,89 ind/crab), dan Octolasmis sp. (9,90 ind/crab). Based on Ministerial Decree of Ministry Environment and Forestry No. 1 of 2004 water quality in Wonorejo Mangrove Forest was still optimal for life cycle of mud crab with average of temperature is 31,20°C, Dissolved Oxygen 5,53 mg/l, salinity 11 ppt, and pH 7,40.
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Das, Kumar Prasun, Subrata Mondal i Abdulla Al Asif. "Growth and economic performance of different supplementary feed on female mud crab (Scylla olivacea) fattening in plastic box". Asian Journal of Medical and Biological Research 5, nr 4 (3.02.2020): 303–15. http://dx.doi.org/10.3329/ajmbr.v5i4.45269.
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The present study was conducted to identify low cost feed for female mud crab (Scylla olivacea) fattening practice in plastic box and the effect of different feeds on growth and survival rate of mud crab. A number of 30 adult non-gravid female crabs were reared into rectangular shaped plastic boxes, each box containing one crab. Three types of feed such as Chicken intestine, Tilapia and Apple Snail meat were supplied as feed at 10% of body weight of the crabs once daily considered as Treatment-1, Treatment-2 and Treatment-3 respectively with 10 replications each to compare the fattening system.. The crabs in plastic boxes were floating into water to fatten for 10 days. Survival rate of crab was found 100%, 90% and 100% respectively in chicken intestine, tilapia and apple snail meat. In the experiment food conversion ratio (FCR) and specific growth rate in weight (SGRw) were varied significantly among different foods (P >0.05). Comparative benefit-cost analysis showed that use of chicken intestine as feed in crab fattening attained higher net profit than crab fattening used tilapia and apple snail s feed from 7-12 days fattening period The present study revealed that utilization of chicken intestine as feed for mud crab fattening might be better than any other feeds and cost effective in Bangladesh.
Asian J. Med. Biol. Res. June 2019, 5(4): 303-315
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Poulin, Remington X., Serge Lavoie, Katherine Siegel, David A. Gaul, Marc J. Weissburg i Julia Kubanek. "Chemical encoding of risk perception and predator detection among estuarine invertebrates". Proceedings of the National Academy of Sciences 115, nr 4 (8.01.2018): 662–67. http://dx.doi.org/10.1073/pnas.1713901115.
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An effective strategy for prey to survive in habitats rich in predators is to avoid being noticed. Thus, prey are under selection pressure to recognize predators and adjust their behavior, which can impact numerous community-wide interactions. Many animals in murky and turbulent aquatic environments rely on waterborne chemical cues. Previous research showed that the mud crab, Panopeus herbstii, recognizes the predatory blue crab, Callinectus sapidus, via a cue in blue crab urine. This cue is strongest if blue crabs recently preyed upon mud crabs. Subsequently, mud crabs suppress their foraging activity, reducing predation by blue crabs. Using NMR spectroscopy- and mass spectrometry-based metabolomics, chemical variation in urine from blue crabs fed different diets was related to prey behavior. We identified the urinary metabolites trigonelline and homarine as components of the cue that mud crabs use to detect blue crabs, with concentrations of each metabolite dependent on the blue crab’s diet. At concentrations found naturally in blue crab urine, trigonelline and homarine, alone as well as in a mixture, alerted mud crabs to the presence of blue crabs, leading to decreased foraging by mud crabs. Risk perception by waterborne cues has been widely observed by ecologists, but the molecular nature of these cues has not been previously identified. Metabolomics provides an opportunity to study waterborne cues where other approaches have historically failed, advancing our understanding of the chemical nature of a wide range of ecological interactions.
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HARUN, NOR OMAIMA, NIK NUR SHAHIERA CHE ABDULLAH i MHD IKHWANUDDIN ABDULLAH. "PEA CRAB DISTRIBUTION AND ITS MORPHOLOGICAL CHARACTERISTICS STUDIED IN BIVALVES FROM SETIU WETLANDS, TERENGGANU". Malaysian Applied Biology 49, nr 4 (25.12.2020): 99–106. http://dx.doi.org/10.55230/mabjournal.v49i4.1598.
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Pea crab is a small crustacean known as kleptoparasite and belongs to the family Pinnotheridae, inhabit bivalves, gastropods, and other species. Nonetheless, pea crab is one of the unfamiliar species to the Malaysia citizen and the information is limited. This study aimed to determine the distribution of pea crab from four bivalves species (mud clam, oyster, hard clam and cockle) in Setiu Wetlands, Terengganu. Sampling was conducted twice, in October 2018 and February 2019, in which mud clam, oyster, cockle and hard clam were collected. In this study, the distribution of pea crab was observed by collecting randomly fifty samples of each bivalve at four sites and checked for any presence of pea crab. The size shell length of mud clams measured was 40 to 75 mm, oysters were 30 to 80 mm, marine clams and cockles were 20 to 40 mm. Pea crab presence was analysed and identified for the genus identification based on the microscopic and macroscopic methods. The result showed that, pea crab only present in the mud clam but none in other bivalves. Fifteen pea crabs were isolated from the first sampling (mean=0.3) with 11 females, whilst 13 pea crabs from the second sampling (mean=0.26) with 10 females- identified. The size of the pea crab measured was between 10 mm to 15 mm and belongs to the genus of Arcotheres sp. However, there were other none pea crab species were found in the oyster. On the other hand, the correlation between the carapace width of pea crab and mud clam shell length were analysed using linear regression (r²=0.0699, p=0.341) from first sampling, while (r²=0.2885, p=0.058) from second sampling. The size range of mud clams without pea crab was 35 to 60 mm shell length.
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Gita, Rina Sugiarti Dwi, Sudarmadji Sudarmadji i Joko Waluyo. "The Influence of Abiotic Factors on The Diversity and Abudance of Mangrove Crabs (Scylla spp.) in Blok Bedul Alas Purwo National Park Mangrove Forest". Jurnal ILMU DASAR 16, nr 2 (22.11.2016): 63. http://dx.doi.org/10.19184/jid.v16i2.1517.
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The purpose of this study was to determine the diversity, abundance and abiotic factors influence the diversity and abundance of mud crab (Scylla spp.) In mangrove forests Blok Bedul Alas Purwo National Park. This research method uses descriptive quantitative method. Diversity is calculated by using the formula of Shannon Wiener, mangrove crab abundance is calculated using the formula abundance Kreb whereas the method of analysis using simple linear regression. The data used in this research is data such as the number and type of biotic mud crabs and data abiotic form of measurement of temperature, pH, salinity, substrate type, and the tide. This study shows the results include mangrove crab species diversity index of every observation stations in the mangrove forests Blok Bedul Alas Purwo National Park is H '= 0.315 showing that the level of diversity in every station is low. The abundance of mud crabs in the mangrove forests Blok Bedul Alas Purwo National Park is 0.0011 individuals / m² which showed that the level of abundance at relatively low research station. Results of the analysis of the influence of abiotic factors on the diversity and abundance of mud crabs in mangrove forests Blok Bedul National Park Alas Purwo not significant (p> 0.05) the diversity and abundance of mangrove crab. Keywords : abiotic factors , abundance , diversity , mud crab , regression
Rozprawy doktorskie na temat "Mud crab"
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Pavasovic, Marko. "Digestive profile and capacity of the mud crab (Scylla serrata)". Thesis, Queensland University of Technology, 2004. https://eprints.qut.edu.au/15973/1/Marko_Pavasovic_Thesis.pdf.
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Commercial farming of mud crab Scylla serrata is a significant industry throughout South East Asia. The limited scientific knowledge of mud crab nutritional requirements and digestive processes, however, is recognised as a
major constraint to the future growth of this industry. To better understand the
mechanisms of digestion in the mud crab we have analysed the diversity of digestive enzymes from the hepatopancreas. Significant protease, amylase,cellulase and xylanase activities were detected in soluble extracts from this
organ.
Temperature profiles for all enzymes were basically similar with optimal activities observed at 500C. Examination of pH tolerance revealed optimal activities for protease and amylase at pH 7.0 while optimal activities for
cellulase and xylanase were observed at pH 5.5. Under optimum conditions,protease and amylase activities were approximately two orders of magnitude greater than those seen for either cellulase or xylanase. Interestingly,
hepatopancreatic extracts were able to liberate glucose from either starch or carboxymethyl (CM)-cellulose suggesting that a range of carbohydrates may be utilised as energy sources. The effects of dietary carbohydrates on feed
digestibility, digestive enzyme levels and growth were also studied by inclusion of additional starch or CM-cellulose at the expense of casein in formulated diets. It was shown that amylase, cellulase and xylanase activities
in extracts from the hepatopancreas were highest in mud crabs fed diets containing 47% carbohydrate. Based on the findings, we suggest that the ability of the mud crab to modulate digestive enzyme activities may represent
a mechanism to maximise access to essential nutrients when the dietary profile changes.
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Pavasovic, Marko. "Digestive profile and capacity of the mud crab (Scylla serrata)". Queensland University of Technology, 2004. http://eprints.qut.edu.au/15973/.
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Commercial farming of mud crab Scylla serrata is a significant industry throughout South East Asia. The limited scientific knowledge of mud crab nutritional requirements and digestive processes, however, is recognised as a major constraint to the future growth of this industry. To better understand the mechanisms of digestion in the mud crab we have analysed the diversity of digestive enzymes from the hepatopancreas. Significant protease, amylase,cellulase and xylanase activities were detected in soluble extracts from this organ. Temperature profiles for all enzymes were basically similar with optimal activities observed at 500C. Examination of pH tolerance revealed optimal activities for protease and amylase at pH 7.0 while optimal activities for cellulase and xylanase were observed at pH 5.5. Under optimum conditions,protease and amylase activities were approximately two orders of magnitude greater than those seen for either cellulase or xylanase. Interestingly, hepatopancreatic extracts were able to liberate glucose from either starch or carboxymethyl (CM)-cellulose suggesting that a range of carbohydrates may be utilised as energy sources. The effects of dietary carbohydrates on feed digestibility, digestive enzyme levels and growth were also studied by inclusion of additional starch or CM-cellulose at the expense of casein in formulated diets. It was shown that amylase, cellulase and xylanase activities in extracts from the hepatopancreas were highest in mud crabs fed diets containing 47% carbohydrate. Based on the findings, we suggest that the ability of the mud crab to modulate digestive enzyme activities may represent a mechanism to maximise access to essential nutrients when the dietary profile changes.
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Mirera, David Oersted. "Capture-based mud crab (Scylla serrata) aquaculture and artisanal fishery in East Africa- Practical and ecological perspectives : Mud crab ecology and aquaculture". Doctoral thesis, Linnéuniversitetet, Institutionen för biologi och miljö (BOM), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-32399.
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Mud crab Scylla serrata is a crustacean that spends most of its life cycle in the mangrove environment throughout its range. Fishery and aquaculture of this crab are significant economic activities in coastal areas in the tropics and sub-tropics because of the meat quality and nutritional value. However there is a significant shortage of information on the ecology, fishery and aquaculture of these crabs in sub-Saharan Africa. This impacts the development of a sustainable aquaculture and fishery for the benefit of coastal communities. The present study analyses various aspects of mud crab ecology, fishery, aquaculture and social economics in East Africa using multidisciplinary approaches. The results are given in seven papers based on field and laboratory studies. The study established for the first time that high intertidal mangrove back-flats constitute a key habitat for the earliest instars of S. serrata (4 -30 mm CW). It also showed that diurnal tidal migration behaviour occurs in small juveniles that migrate to sub-tidal habitats during the day, possibly due to variable predation risks. Monthly sampling of juveniles in Kenya and Tanzania indicated continuous recruitment throughout the year. The large numbers of juvenile crabs along mangrove fringes indicate that these habitats could serve as sites suitable for collection of juvenile crabs for aquaculture. However, these areas must also be managed and protected to support the recruitment to the wild crab populations. An assessment of the crab fishery indicated that artisanal crab fishers possess significant traditional knowledge mainly inherited from their parents that enabled them to exploit the resource. Such knowledge could be useful for the development of the aquaculture and in management of the fishery. Mud crab fishing was found to be a male dominated activity, and fishers on foot practiced fishing in burrows at spring low tides. Interviews indicated that the average size of marketable crabs has declined over the years and a weak management system was observed with most fishers operating without a license. Due to the knowledge required regarding the local conditions, fishers are unable to shift to new areas. Furthermore fishers and could not fish at neap tides. Such limitations provide a “natural closure” of the fishery. Also foot fishers cover fairly limited distances in their daily operations, an aspect that can be utilized to effect site-specific management for the fishery if necessary. Laboratory and field experiments indicated that cannibalistic interactions are heavily influenced both by size differences of crabs and the availability of shelter but no significant effect was found for different stocking densities. Such information is of direct importance for crab farmers in East Africa, where seed from the wild are of multiple sizes and there is a need to grade juvenile crabs and provide shelter at stocking to ensure maximum survival. Experimental studies in earthen pond and mangrove pen cultures indicated high mortality rates. Comparing growth in earthen pond and mangrove pen systems indicated that growth rates were generally high in both systems, but significantly lower in pen systems without shelter, suggesting that shelter may have a stronger effect on growth than has been previously thought. Similar to artisanal mud crab fishery, an assessment of small-scale mud crab farming by organized community groups in Kenya indicated low level of women participation. A good knowledge of the market existed among the mud crab farming groups where hotels and exporters offered the highest prices. However there is a need for national policies to be directed to support small-scale aquaculture development by ensuring training and capacity building for women, operation and management of groups, data management and provision of user rights for communities working in the mangrove environment. Market analyses showed that the common market size of crabs in East Africa ranged between 500-1000 g and are thus larger than in Southeast Asia where the average size is reported at 300 g. Prices for mud crabs were over 50 % lower in Tanzania than in other East African countries and most of the profit was earned by middlemen and exporters. Cost revenue analysis showed that it would be more profitable to farm smaller commercial crabs, and develop a market for 300 g crabs to increase the profitability of crab farming in East Africa. Also, the same analyses found that farming large crabs in individual cages, which is the dominant culture form in East Africa today, had very low profitability due to high labor costs and low growth rates. Using a step-wise function of natural growth it was shown that growth rates of S. serrata cultured in cages was 40 % of the growth rates obtained in experimental pond and pen cultures, which were similar to natural growth. Therefore the good performance of grow-out cultures of juvenile mud crabs in earthen ponds and mangrove pens showed a potential to develop into a profitable and sustainable intervention. However, more work is needed to improve survival in culture systems and address the identified limitations of crab seeds and feed to enable development of sustainable mud crab aquaculture in East Africa.
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Gopurenko, David, i n/a. "Genetic Structure Within the Distribution of the Indo-West Pacific Mud Crab Scylla serrata (Forskal, 1775)". Griffith University. Australian School of Environmental Studies, 2003. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20030926.124631.
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It is often hypothesised that marine species with mobile planktonic phases are capable of widespread dispersal and may therefore be genetically homogenous throughout their distribution. Studies that have demonstrated positive correlation between duration of plankton phase and levels of gene flow reinforce the prediction that life history characteristics of marine species determine the potential extent of genetic and demographic connectivity throughout their distributions. This prediction has however been challenged by studies that have employed genetic markers highly sensitive to both historical and contemporary demographic changes. Disparities between dispersal potential and measured levels of gene flow have been demonstrated both among historically disconnected ocean basins and within semi-enclosed areas of strong hydraulic connectivity. These studies and others highlight a need for greater focus on factors that may influence population structure and distribution for marine species. In this thesis, I have examined genetic structure within and among populations of an estuarine species of mud crab Scylla serrata (Forskal, 1775) using a number of genetic markers and methods. The species is widely distributed throughout mangrove and estuarine habitats of the Indo - West Pacific (IWP); it is generally assumed that life-history characteristics of S. serrata promote high levels of population admixture and gene flow throughout its distribution. Alternatively, factors that have promoted population genetic structure for a variety of IWP marine species may also have affected S. serrata populations. By investigating genetic structure at several spatial scales of sampling, I was able to address a variety of hypotheses concerning the species distribution, dispersal, and genetic structure. Episodic changes to marine habitat and conditions experienced within the IWP during the Pleistocene may have affected genetic structure for a broad variety of marine taxa. The relative strength of this hypothesis may be assayed by comparative genetic studies of widespread IWP taxa with high dispersal capacity. In order to ascertain levels of historical and contemporary gene flow for S. serrata, I investigated the phylogeographic distribution of mitochondrial DNA haplotypes sampled throughout the species range. Adults were sampled from three west Indian ocean locations (N=21), six west Pacific sites (N=68), and two sites from northern eastern Australia (N=35). Temperature gradient gel electrophoresis and sequencing of 549 base pairs of the mitochondrial cytochrome oxidase I (COI) coding gene identified 18 distinct haplotypes. Apart from that seen in northern Australia, haplotype diversity was low (h < 0.36) at each of the locations. Total nucleotide diversity in the entire sample (excluding northern Australian locations) was also low (p = 0.09). Haplotypes clustered into two clades separated by approximately 2% sequence divergence. One clade was widespread throughout the IWP (clade 1) whereas the other was strictly confined to northern Australia (clade 2). Genealogical assessment of sequenced haplotypes relative to their distributions suggested that a historical radiation of clade 1 S. serrata throughout the IWP occurred rapidly and recently (<1Myr bp) from a west Pacific origin. The evidence of fixed unique haplotypes at the majority of locations suggested that contemporary maternal gene flow between trans-oceanic sites was limited. Contrary to reports for other widespread species of IWP taxa, there was no evidence of lengthy periods of regional separation between Indian from Pacific Ocean populations. However, results may indicate a separation of northern Australian crabs from other locations before and during the IWP radiation. I speculated that this isolation might have resulted in the formation of a new species of Scylla. Additional sampling of mud crabs from the Australian coastline allowed an examination of the diversity and distribution of clade 1 and 2 haplotypes among recently formed shelf-connected coastal locations, and across a historical bio-geographic barrier. Over 300 individuals were sampled from multiple locations within coastal regions (western, northern and eastern) of Australia and analysed for mutational differences at the COI gene. Analysis of molecular variance partitioned by sampling scale (Among regions, within regions, and within all locations) indicated mitochondrial haplotypes were structured regionally (P < 0.001), which contrasted with evidence of genetic panmixia within regions. Regional genetic structure broadly correlated with hydrological circulation, supporting the contention that release and transport of propagules away from the estuary may allow genetic connectivity among widespread shelf-connected S. serrata populations. That similar patterns of maternal gene flow were absent among trans-oceanic populations may indicate that the spatial scale of effective dispersal for this species is generally limited to areas of coastal shelf. The two clades of haplotypes were geographically separated either side of the Torres Strait, a narrow sea channel connecting the northern and eastern regions of coastal Australia. This pattern of historical genetic separation was concordant with a number of other marine species across northern Australia, and might indicate a shared history of vicariance induced by eustasy. Alternatively, differences in diversity and distribution of the clades may be evidence of two independent expansions of clade 1 and 2 crab populations into Australian regions following post-glacial estuary formation. Overall, despite evidence of genetic panmixia within extensive sections of the Australian distribution, there was also evidence of significant barriers to maternal gene flow with both shallow and deep regional phylogeographic assortment of mtDNA haplotypes. The presence of these barriers indicated both historical and contemporary factors have imposed limits to effective dispersal by this species among coastal habitats. A subset of the Australian sample (8 locations, N = 188) was also examined for variation at five microsatellite loci developed specifically here for S. serrata. I examined variation among samples at each of the loci to: a) independently verify regional structure among crab populations previously detected using the mtDNA analysis; b) test for evidence of co-distributed non-interbreeding stocks of S. serrata within Australian waters by examining samples for segregation of alleles within microsatellite loci concordant with the two mtDNA clades. The frequency and distribution of alleles for each of the highly polymorphic microsatellites were homogenous at all levels of sample partitioning and contrasted sharply with the instances of both weak and strong regional phylogeographic assortment of mtDNA haplotypes. These contrasting results between different genomic markers were examined in relation to the species life history, and to differences in mutational rate and inheritance of the genetic markers. Several hypotheses may explain the disparity, however it is most likely that rampant homoplasy and high rates of mutation at the microsatellite in conjunction with large Ne at locations may be concerted to delay equilibrium between genetic drift and migration among populations at these highly polymorphic nuclear markers. There was also no evidence that alleles at microsatellite loci were co-segregated with mtDNA clades and therefore no evidence of segregated breeding between the clades of crabs. Whether or not this result was also driven by homoplasy at the microsatellites remains unknown. Recently established mud crab populations (~ 3-4 years old) observed in a number of southwest Australian estuaries are almost 1000 kilometres south of their previously recorded distribution on the Western Australian coast. Colonisation of the southwest region may have occurred either by a natural range expansion from northwest Australian mud crab populations or by means of translocation from any number of mud crab sources within the Indo - West Pacific. I used mtDNA analysis to verify the species and determine the potential source population(s) of the colonists, by comparing sampled genetic material from the southwest (N = 32) against that previously described for the genus. I also compared levels of diversity at mtDNA and two microsatellite loci between the colonist and suspected source population(s) to qualitatively determine if the southwest populations experienced reductions in genetic diversity as a result of the colonisation process. All colonist samples had S. serrata mtDNA COI sequences identical to one previously described as both prevalent and endemic to northwest Australia. High levels of genetic diversity among source and colonist populations at two microsatellite loci contrasted to the mitochondrial locus which displayed an absence of variation among colonists compared to moderately diverse source populations. I argued that the southwest was recently colonised by large numbers of S. serrata propagules derived from the northwest of Australia, possibly due to an enhanced recruitment event coinciding with the reported strengthening of the Leeuwin Current during 1999. Contrasting levels of diversity among nuclear and mitochondrial loci may be attributed to a difference in response by the two genomes to the colonisation process. I predict that such differences may be generally prevalent among plankton-dispersed species. Finally, I discuss aspects of the species distribution and biogeography obtained as a composite of the various results and ideas expressed in this thesis. I propose that S. serrata populations in the IWP may have experienced several cycles of extinction and population retraction from temperate areas followed by subsequent periods of colonisation and rapid coastal expansion in response to the effects of glacial episodes on coastal habitats in the IWP. I propose that persistence of this species as remnant populations of clade 1 and 2 crabs at equatorial locations during low sea level stands provided source populations for later expansions by the species into a variety of coastal areas throughout the IWP. Further analysis is required to determine if mtDNA clade 1 and 2 crabs are non-interbreeding species of mud crab.
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Le, Van Chi. "Genetic resources in wild and cultured stocks of the Asian mud crab, Scylla paramamosain". Thesis, Queensland University of Technology, 2010. https://eprints.qut.edu.au/39232/1/Van_Chi_Le_Thesis.pdf.
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The mud crab (Scylla spp.) aquaculture industry has expanded rapidly in recent years in many countries in the Indo - West Pacific (IWP) region as an alternative to marine shrimp culture because of significant disease outbreaks and associated failures of many shrimp culture industries in the region. Currently, practices used to produce and manage breeding crabs in hatcheries may compromise levels of genetic diversity, ultimately compromising growth rates, disease resistance and stock productivity. Therefore, to avoid “genetic pollution” and its harmful effects and to promote further development of mud crab aquaculture and fisheries in a sustainable way, a greater understanding of the genetic attributes of wild and cultured mud crab stocks is required. Application of these results can provide benefits for managing wild and cultured Asian mud crab populations for multiple purposes including for commercial production, recreation and conservation and to increase profitability and sustainability of newly emerging crab culture industries. Phylogeographic patterns and the genetic structure of Asian mud crab populations across the IWP were assessed to determine if they were concordant with those of other widespread taxa possessing pelagic larvae of relatively long duration. A 597 bp fragment of the mitochondrial DNA COI gene was amplified and screened for variation in a total of 297 individuals of S. paramamosain from six sampling sites across the species’ natural geographical distribution in the IWP and 36 unique haplotypes were identified. Haplotype diversities per site ranged from 0.516 to 0.879. Nucleotide diversity estimates among haplotypes were 0.11% – 0.48%. Maximum divergence observed among S. paramamosain samples was 1.533% and samples formed essentially a single monophyletic group as no obvious clades were related to geographical location of sites. A weak positive relationship was observed however, between genetic distance and geographical distance among sites. Microsatellite markers were then used to assess contemporary gene flow and population structure in Asian mud crab populations sampled across their natural distribution in the IWP. Eight microsatellite loci were screened in sampled S. paramamosain populations and all showed high allelic diversity at all loci in sampled populations. In total, 344 individuals were analysed, and 304 microsatellite alleles were found across the 8 loci. The mean number of alleles per locus at each site ranged from 20.75 to 28.25. Mean allelic richness per site varied from 17.2 to 18.9. All sites showed high levels of heterozygosity as average expected heterozygosities for all loci ranged from 0.917 – 0.953 while mean observed heterozygosity ranged from 0.916 – 0.959. Allele diversities were similar at all sites and across all loci. The results did not show any evidence for major differences in allele frequencies among sites and patterns of allele frequencies were very similar in all populations across all loci. Estimates of population differentiation (FST) were relatively low and most probably largely reflect intra – individual variation for very highly variable loci. Results from nDNA analysis showed evidence for only very limited population genetic structure among sampled S. paramamosain, and a positive and significant association for genetic and geographical distance among sample sites. Microsatellite markers were then employed to determine if adequate levels of genetic diversity has been captured in crab hatcheries for the breeding cycle. The results showed that all microsatellite loci were polymorphic in hatchery samples. Culture populations were in general, highly genetically depauperate, compared with comparable wild populations, with only 3 to 8 alleles recorded for the same loci set per population. In contrast, very high numbers of alleles per locus were found in reference wild S. paramamosain populations, which ranged from 18 to 46 alleles per locus per population. In general, this translates into a 3 to 10 fold decline in mean allelic richness per locus in all culture stocks compared with wild reference counterparts. Furthermore, most loci in all cultured S. paramamosain samples showed departures from HWE equilibrium. Allele frequencies were very different in culture samples from that present in comparable wild reference samples and this in particular, was reflected in a large decline in allele diversity per locus. The pattern observed was best explained by significant impacts of breeding practices employed in hatcheries rather than natural differentiation among wild populations used as the source of brood stock. Recognition of current problems and management strategies for the species both for the medium and long-term development of the new culture industry are discussed. The priority research to be undertaken over the medium term for S. paramamosain should be to close the life cycle fully to allow individuals to be bred on demand and their offspring equalised to control broodstock reproductive contributions. Establishing a broodstock register and pedigree mating system will be required before any selection program is implemented. This will ensure that sufficient genetic variation will be available to allow genetic gains to be sustainably achieved in a future stock improvement program. A fundamental starting point to improve hatchery practices will be to encourage farmers and hatchery managers to spawn more females in their hatcheries as it will increase background genetic diversity in culture stocks. Combining crablet cohorts from multiple hatcheries into a single cohort for supply to farmers or rotation of breeding females regularly in hatcheries will help to address immediate genetic diversity problems in culture stocks. Application of these results can provide benefits for managing wild and cultured Asian mud crab populations more efficiently. Over the long-term, application of data on genetic diversity in wild and cultured stocks of Asian mud crab will contribute to development of sustainable and productive culture industries in Vietnam and other countries in the IWP and can contribute towards conservation of wild genetic resources.
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Nguyen, Thi Bich Ngoc. "Commercial mud crab Scylla Serrata : Study on growth, energy and protein requirement of juveniles in the view to develop peleted feed for crab farming in New Caledonia". Thesis, Nouvelle Calédonie, 2014. http://www.theses.fr/2014NCAL0057/document.
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En Nouvelle-Calédonie il y a une forte volonté politique pour diversifier l'aquaculture qui repose encore aujourd'hui sur la crevetticulture. Dans ce contexte le crabe de palétuvier est considéré comme une espèce à fort potentiel. Un des principaux verrous au développement de la carcinoculture en Nouvelle-Calédonie est la disponibilité d'un aliment granulé commercial. Ainsi le principal objectif de cette thèse est d'améliorer notre connaissance des besoins nutritionnels du crabe de palétuvier afin d'être en mesure de formuler un aliment équilibré pour son élevage. Cependant avant d'aborder les études nutritionnelles nous avons vérifié le nombre d'espèces de crabes de palétuvier présentes en Nouvelle-Calédonie.Nos résultats d'études morphologiques et génétiques de 63 individus provenant de 9 sites des côtes Ouest et Nord-Est de la Nouvelle-Calédonie ont confirmé l'existence d'une unique espèce commercialisée: Scylla serrata. C'est donc sur cette espèce que nous avons travaillé en nutrition avec deux séries expérimentales ayant pour objectifs: i) d'évaluer le concentré protéique de soja (CPS) en comparaison avec la farine de poisson comme principale source en protéines et ii) de déterminer le taux optimum d'incorporation du CPS pour la mue et la croissance tissulaire des animaux. Nous avons ainsi observé deux phases de croissance tissulaire au cours d'un cycle de mue (CM): une phase rapide (CTR) qui démarre après la mue et dure jusqu'au début de l'intermue (elle représente 30% du CM) suivi d'une phase de croissance lente (CTL) sur toute la durée de l'intermue et jusqu'à la mue suivante (elle représente 70% du CM). L'accumulation des protéines et des lipides au cours du CM a suivi le même profil de croissance tissulaire contrairement aux cendres qui ont augmenté de façon rapide durant 5 jours suivant l'ecdysis pour atteindre un plateau jusqu'à la prochaine mue. Les deux phases de croissance étaient corrélées avec une prise de l'aliment par les animaux maximale pendant les deux premières semaines suivant la mue. Elle a diminué de moitié sur les 5 semaines suivantes et s'est maintenue ensuite à un niveau de base jusqu'à la prochaine mue. L'énergie ingérée était allouée principalement à la croissance et à l'entretient respectivement durant les périodes CTR et CTL. Durant la phase de croissance lente, 28% de l'énergie ingérée étaient mise en réserve en prévision de la prochaine mue. Le remplacement de la farine de poisson par la CPS n'a pas modifié la croissance tissulaire,l'efficience de l'aliment et le bilan énergétique des animaux quelque soit la phase de croissance considérée. Le taux d'incorporation dans l'aliment de 42% de CPS a permis la meilleure croissance (fréquence de mue et croissance tissulaire, efficience de l'aliment et la rétention de l'énergie des protéines et des lipides. L'hypothèse d'une toxicité de l'ammonium issu de la dégradation des protéines en excès ou des facteurs antinutritionnels du soja est avancée pour expliquer les effets négatifs observés avec les aliments renfermant des taux d'incorporation élevés en CPS. En conclusion, nos travaux apportent des informations originales sur la croissance tissulaire et les dépenses énergétiques durant un cycle de mue et la capacité du crabe juvénile d'utiliser le CPS comme principale source de protéines. Sur ces bases nous somme en mesure de préconiser des contraintes nutritionnelles permettant de formuler un aliment équilibré sans farine de poissons pour l'élevage du crabe de palétuvier S.serrataIn New Caledonia, there is the strong political will to diversify aquaculture which is mainly based on shrimp farming. In this context, mud crabs have been considered as a potential species for aquaculture development. One of the main constraints to develop crab farming is the availability of formulated feed. Thus, the main purpose of this thesis is to get information on the crab nutritional requirements in order to formulate a balanced diet. However, we had to clarify first how many species of mud crab were present in New-Caledonia. The result of our morphological and genetic investigations carried out on 63 specimens from 9 areas of the west and northeast coast of New-Caledonia confirmed that only one species, Scylla serrata, is commercialized in this country. Consequently, S. serrata was used in our nutritional study based on two experiments to: i) evaluate the soy protein concentrate (SPC) compared with the fishmeal as the main protein source and ii) determine the optimum level of SPC in the diet for molting and tissue growth. We observed two tissue growth phases within one molt cycle (MC): a fast tissue growth (FTG) occurred after ecdysis until early intermolt stage (30% of MC) which is followed by a slow tissue growth (STG) period from intermolt to ecdysis (70% of MC). Protein and lipid deposition followed the same trend than tissue growth while ash level increased quickly during five days after molt and then remained stable until the next molt. The two growth phases were correlated with the voluntary feed intakes (VFI) which was maximum during 2 weeks after ecdysis and then decreased by 50% over the five following weeks to reach a baseline until the next molt. Intake energy was allocated mainly for growth during FTG period and for maintenance during STG period. During STG, 28% of the ingested energy was accumulated for the next ecdysis. Replacement of fishmeal by SPC as main protein source did not affect tissue growth, efficiency of feed utilization and energy budget of crabs whatever the tissue growth period considered. The dietary SPC inclusion of 42% in the diet promoted growth (molt frequency and tissue growth), feed efficiency and retention of energy, protein and lipid. Hypothesis related to ammonia toxicity from catabolism of proteins in excess or anti-nutritional factors from soybean could explain the negative effects of higher inclusion of SPC in the diet for juvenile crabs. In conclusion, our work brings novel information on tissue growth, energy budget during a molt cycle and the ability of juvenile crab to use SPC as a main source of protein. On this basis we suggest to formulate nutritionally balanced diet without fishmeal to farm juvenile mud crabs S. serrata
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Sanoara, Yasmin. "Enhancing the Sustainable Livelihood of Crab Fishers: A Study of the Mud Crab Value Chain of Coastal Bangladesh Using the Social Business Model". Thesis, Curtin University, 2018. http://hdl.handle.net/20.500.11937/70493.
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This study investigates how to enhance sustainable livelihood of mud-crab fishers of Bangladesh in the premise of the existing cumbersome and manipulative value chain that threatens fishers’ livelihood. Guided by the social business model, the study proposes a revised cooperative-based crab value chain; and unveils that individual and channel factors influence the benefits and barriers of the proposed cooperative. This eventually influences fishers’ attitude and intention towards cooperative and thus helps achieve their sustainable livelihood.
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Ong, Moc Quy. "Supplementing probiotics during early stages of mud crab (Scylla paramamosain) culture under various rearing systems". Thesis, Curtin University, 2018. http://hdl.handle.net/20.500.11937/78345.
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The study aimed to improve megalopa and crablets production of mud crab, Scylla paramamosain, through dietary supplementation of probiotics and locally available diets under various rearing systems. The results concluded that the probiotic-enriched live food fed until the late zoeal stage in a green water culture system increased the megalopa production. Megalopa fed live Acetes resulted in increased survival. However, the production of crablets and not megalopa, was compromised when green water culture was employed.
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Roche, Dominique. "Discovery, distribution, and eradication potential of the introduced mud crab, «Rhithropanopeus harrisii», in the Panama Canal". Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=32379.
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Eradication of invasive species is an eminent concept in conservation biology. After prevention is no longer an option, many ecologists argue that eradication is the most effective way to mitigate the risk of impacts from invasive species, given the elevated costs and often prolonged environmental effects of long-term control strategies. In the majority of systems, eradication is most likely to succeed early in the invasion process, when an invader is localized. However, rarely is early eradication considered in practice. This paradox may result from the many uncertainties regarding the future spread and impacts of novel invaders and managers lacking practical guidance to make logical decisions to manage them. In this thesis, I use a case study of an introduced mud crab, Rhithropanopeus harrisii, to propose guidelines for rapidly assessing and communicating the feasibility and the benefits of early eradication. First, I document the recent discovery of an established population of R. harrisii in the Panama Canal, highlighting how maritime traffic in this hub of international shipping may further increase the spread of this invader worldwide. Second, I evaluate the distribution, abundance, and demographics of R. harrisii across the Panama Canal with a standardized quantitative survey; I also assess the crab's potential for spread beyond its distribution in the Canal with two laboratory experiments. Third, I develop an analytical framework for evaluating the feasibility of a rapid response to eradicate R. harrisii and for communicating the potential benefits of this management strategy to decision-makers. My results indicate that R. harrisii currently occupies a limitedL'éradication d'espèces introduites invasives est un concept populaire dans le domaine de la biologie de la conservation. Lorsque la prévention d'une invasion échoue, de nombreux écologistes soutiennent que l'éradication est la méthode la plus efficace afin d'éviter que les espèces introduites ne causent de dommages, considérant les coûts élevés et les effets parfois prolongés du contrôle à long-terme. Notamment, dans la majorité des systèmes, le succès d'un programme d'éradication est supérieur s'il est entrepris tôt lors du processus d'envahissement, lorsqu'une espèce est peu dispersée. Cependant, cette stratégie qui consiste à éradiquer les espèces introduites de façon hâtive est rarement mise en pratique. Ce paradoxe peut résulter d'un haut niveau d'incertitude concernant le potentiel qu'ont les espèces nouvellement introduites à se propager et à causer des impacts, et par le fait que les administrateurs responsables de leur gestion manquent souvent de conseils pratiques afin de réagir promptement suite à leur découverte. Pour remédier à cette lacune, cette thèse se base sur une importante étude de cas et suggère un modèle théorique servant à analyser de façon rapide la possibilité d'implémenter un programme d'éradication hâtif et d'en évaluer les bénéfices. Premièrement, je documente la découverte récente du crabe Rhithropanopeus harrisii dans le Canal de Panama. Le Canal de Panama est une plaque tournante du trafic maritime international et pourrait jouer un rôle important dans l'accroissement de la propagation de R. harrisii au niveau mondial. Deuxièmement, au moyen d'un échantillonnage quantitatif stand
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Churchill, Giles John. "An investigation into the captive spawning, egg characteristics and egg quality of the mud crab (Scylla serrata) in South Africa". Thesis, Rhodes University, 2004. http://hdl.handle.net/10962/d1015963.
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The source of a reliable supply of seed is one of the most important factors determining the success of aquaculture. At present mud crab culture is reliant on wild caught juveniles, which limits the expansion of mud crab farming globally. This, coupled with the paucity of knowledge of the spawning and egg characteristics of mud crabs, prompted the investigation into the captive spawning, incubation and egg quality of Scylla serrata in South Africa. A total of 112 mature females were caught from three estuaries in northern KwaZulu Natal and acclimated to captive conditions. Mature females were present in the estuaries throughout the year and ranged from 90 to 200 mm carapace width. Except for 40 crabs all the females spawned in captivity. On average spawning took place 38 ± 23 days after capture but was not dependent on crab size. Fecundity was significantly correlated to crab size (p = 0.026), with larger females producing more eggs. The average fecundity per batch was 5.79 ± 2.07 million eggs. Hatch success rate for all egg batches was high averaging 84 ± 6 %. Egg dropping occurred in all egg batches during incubation. On average 6.5 % of the egg mass was dropped during incubation. At the average temperature of 27⁰C eggs in the incubation system hatched within 292 ± 12 hours after extrusion. In-vitro incubation of eggs proved to be an ineffective means of incubating Scylla serrata eggs with a hatch success rate of only 25 ± 5 %. Egg quality was assessed both directly, using variables such as hatch success rate and hatch synchronicity and retrospectively by using stress tests and comparing survival of larvae from different coloured egg batches. Lipid class composition and fatty acid methyl ester content for 28 batches of eggs and 16 batches of larvae were analyzed. The biochemical composition of the egg was correlated to survival of larvae in the stress tests to ascertain if the lipid content of the eggs determines their quality. Stress tests were used to retrospectively assess egg quality. Four stressors were administered to newly hatched larvae and the LD50 values recorded. An average LD50 of 64 hours was recorded for the starvation tests, 40% for the salinity tests, 37 ppm for the formalin tests and 39.7 mg/l NH3 for the ammonia stress tests was recorded. Egg colour ranged from pale yellow to orange-red. Egg colour was not influenced by female size or the time the females spent in captivity prior to spawning. Egg colour can therefore not be used as an indicator of quality. The lipid profiles of newly extruded eggs had no effect on hatch synchronicity or hatch success rate. However, the stress tests identified female size (p ≤ 0.02), DHA content of the egg (p ≤ 0.02), Σ omega-3 fatty acids of eggs (p ≤ 0.02) and EPA content of eggs (p ≤ 0.007) as possible determinants of egg quality. Larger crabs tended to produce poorer quality eggs. Egg quality also decreased as the amount of DHA, EPA and the Σ omega-3 fatty acids decreased in the eggs. To summarize, the results of this study indicated that the following parameters affect egg quality - crab size, DHA, EPA and Σ omega-3 fatty acid content of eggs.
Książki na temat "Mud crab"
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Southeast Asian Fisheries Development Center. Aquaculture Dept. Library & Documentation Services. Mud crab bibliography. Tiobauan, Iloilo, Philippines: Brackishwater Aquaculture Information System, SEAFDEC Aquaculture Dept., 1985.
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Mud crab abstracts. Tigbauan, Iloilo, Philippines: Brackishwater Aquaculture Information System, SEAFDEC Aquaculture Dept., 1989.
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Barrett, Robert G. Mud crab boogie. Pymble, Sydney, NSW: HarperCollins, 1998.
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Kathirvel, M. Mud crab culture in India. Chennai: Central Institute of Brackishwater Aquaculture, 2004.
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Mwaluma, James. Pen culture of mud crab scylla serrata in Mtwapa mangrove system, Kenya: A final report for WIOMSA under MARG 1. Zanzibar]: WIOMSA, 2001.
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Beautiful swimmers: Watermen, crabs, and the Chesapeake Bay. New York: Penguin Books, 1987.
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Warner, William W. Beautiful swimmers: Watermen, crabs, and the Chesapeake Bay. Boston: Little, Brown, 1994.
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Why the crawfish lives in the mud. Gretna, La: Pelican Pub., 2009.
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James, Ransome, red. Aunt Flossie's hats: And crab cakes later. New York: Clarion Books, 1991.
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Hill, Jennifer. Species profiles: Life histories and environmental requirements of coastal fishes and invertebrates (Mid-Atlantic) : blue crab. Washington, DC: Fish and Wildlife Service, U.S. Dept. of the Interior, 1989.
Znajdź pełny tekst źródłaCzęści książek na temat "Mud crab"
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Paterson, Brian D., i David L. Mann. "Mud Crab Aquaculture". W Recent Advances and New Species in Aquaculture, 115–35. Oxford, UK: Wiley-Blackwell, 2011. http://dx.doi.org/10.1002/9781444341775.ch4.
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Li, Yuanyou, Chunxiang Ai i Lijie Liu. "Mud Crab, Scylla paramamosain China's Leading Maricultured Crab". W Aquaculture in China, 226–33. Chichester, UK: John Wiley & Sons Ltd, 2018. http://dx.doi.org/10.1002/9781119120759.ch3_4.
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Warne, Kennedy. "The Old Man and the Mud Crab". W Let Them Eat Shrimp, 38–43. Washington, DC: Island Press/Center for Resource Economics, 2011. http://dx.doi.org/10.5822/978-1-61091-024-8_4.
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Huq, Khandaker Anisul, S. M. Bazlur Rahaman i A. F. M. Hasanuzzaman. "Mud Crab Culture as an Adaptive Measure for the Climatically Stressed Coastal Fisher-Folks of Bangladesh". W Environmental Management and Governance, 175–98. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-06305-8_7.
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Ingle, Ray. "Mud Lobsters (Thalassinoidea)". W Crayfishes, Lobsters and Crabs of Europe, 75–82. Dordrecht: Springer Netherlands, 1997. http://dx.doi.org/10.1007/978-94-011-5872-5_7.
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Murugan, Kadarkarai, Lan Wang, Jiang Shiou Hwang, Jaganathan Anitha, Devakumar Dinesh, Pandiyan Amuthavalli, Murugan Vasanthakumaran, Suresh Kumar i Hans-Uwe Dahms. "Use of Bio-fabricated Silver Nanocomposite Capped with Mud Crab Shell (Scylla serrata) Chitosan for Water Purifications and Sustainable Management of Mosquito Vectors at Stagnant Water System in the Semiarid Zone of Tamil Nadu, India". W Water Resources in Arid Lands: Management and Sustainability, 195–202. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-67028-3_16.
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Hallerman, Eric M., David N. Hata, Michael S. Eackles i Timothy L. King. "Population Genetics and Movement Show Metapopulation Dynamics of Mid-Atlantic Region Horseshoe Crabs". W International Horseshoe Crab Conservation and Research Efforts: 2007- 2020, 41–57. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-82315-3_4.
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Le Vay, Lewis, Vu Ngoc Ut i David A. Jones. "Seasonal abundance and recruitment in an estuarine population of mud crabs, Scylla paramamosain, in the Mekong Delta, Vietnam". W Advances in Decapod Crustacean Research, 231–39. Dordrecht: Springer Netherlands, 2001. http://dx.doi.org/10.1007/978-94-017-0645-2_25.
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Chong, Roger Sie-Maen. "Mud crab Octolasmis spp. infestation". W Aquaculture Pathophysiology, 227–29. Elsevier, 2022. http://dx.doi.org/10.1016/b978-0-323-95434-1.00032-2.
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Sanders, Brenda, Roy B. Laughlin i John D. Costlow. "Growth Regulation in Larvae of the Mud Crab Rhitropanopeus Harrisii". W Crustacean Issues 2, 155–61. Routledge, 2017. http://dx.doi.org/10.1201/9781315140698-4.
Pełny tekst źródłaStreszczenia konferencji na temat "Mud crab"
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Padaunan, Novianto, Zahir Zainuddin i Muhammad Niswar. "Mobile Application For Mud Crab Weight Estimation". W 2018 2nd East Indonesia Conference on Computer and Information Technology (EIConCIT). IEEE, 2018. http://dx.doi.org/10.1109/eiconcit.2018.8878611.
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Ali, Rozniza, i M. Syafieq M. Fauzi. "The use of Local Binary Pattern (LBP) feature extraction Members of the mud crab genus Scylla". W ICAAI 2019: 2019 The 3rd International Conference on Advances in Artificial Intelligence. New York, NY, USA: ACM, 2019. http://dx.doi.org/10.1145/3369114.3369117.
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Xiaoyun Lin, Yuanyu Cao, Zhongbao Li, Wenjing Li, Guiling Zhang, Zhanlin Wang, Ning Wu, Zhihong Zhang i Xinjiang Tian. "Notice of Retraction: Isolation and characterization of ten new polymorphic microsatellite loci of the mud crab, Scylla paramamosain". W 2010 2nd Conference on Environmental Science and Information Application Technology (ESIAT 2010). IEEE, 2010. http://dx.doi.org/10.1109/esiat.2010.5568726.
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Khornchatri, Kanjana. "Distribution of Gamma-aminobutyric acid (GABA) in the central nervous system of the male mud crab, Scylla olivacea". W European Microscopy Congress 2020. Royal Microscopical Society, 2021. http://dx.doi.org/10.22443/rms.emc2020.34.
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Perea, Rossian V., i Enrique D. Festijo. "Analysis of the use of Analytics Platform for the Commercial Value of Mud crab Production using Non-parametric Model". W 2022 IEEE 12th Annual Computing and Communication Workshop and Conference (CCWC). IEEE, 2022. http://dx.doi.org/10.1109/ccwc54503.2022.9720844.
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Suryandari, Asriningsih, Anita Putri Maharsari, Bambang Irawan i Agoes Soegianto. "Length-weight relationship, sex ratio and condition factors of mud crab (Scylla paramamosain Estampador, 1949) from Brantas Estuary, East Java, Indonesia". W INVENTING PROSPEROUS FUTURE THROUGH BIOLOGICAL RESEARCH AND TROPICAL BIODIVERSITY MANAGEMENT: Proceedings of the 5th International Conference on Biological Science. Author(s), 2018. http://dx.doi.org/10.1063/1.5050103.
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de Jager, O. C. "Gamma-rays from the Crab Nebula and other plerions—testing MHD models". W The international symposium on high energy gamma-ray astronomy. AIP, 2001. http://dx.doi.org/10.1063/1.1370788.
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Perea, Rossian V., i Jesus Paolo B. Cullado. "ICT-Assisted Growth Management System for Mud crabs (ICT-AGMAS): Deployment and Evaluation". W 2022 International Conference on Emerging Techniques in Computational Intelligence (ICETCI). IEEE, 2022. http://dx.doi.org/10.1109/icetci55171.2022.9921381.
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Mirzoyan, Razmik, Giacomo D'Amico, Giovanni Ceribella, Yuki Iwamura, Takayuki Saito i Masahiro Teshima. "Absolute Calibration of Mid to Large Size IACTs with P1/P2 of the Crab Pulsar". W 37th International Cosmic Ray Conference. Trieste, Italy: Sissa Medialab, 2021. http://dx.doi.org/10.22323/1.395.0883.
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Salman, N., H. K. Maheshwari, A. H. Kemp i M. Ghogho. "Effects of anchor placement on mean-CRB for localization". W 2011 The 10th IFIP Annual Mediterranean Ad Hoc Networking Workshop (Med-Hoc-Net 2011). IEEE, 2011. http://dx.doi.org/10.1109/med-hoc-net.2011.5970475.
Pełny tekst źródłaRaporty organizacyjne na temat "Mud crab"
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Wills, Gabrielle, Janeli Kotzé i Jesal Kika-Mistry. A Sector Hanging in the Balance: Early Childhood Development and Lockdown in South Africa. Research on Improving Systems of Education (RISE), listopad 2020. http://dx.doi.org/10.35489/bsg-rise-wp_2020/055.
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New evidence suggests that over four months after the closure of early childhood development (ECD) programmes on 18 March 2020, the ECD sector was likely to be operating at less than a quarter of its pre-lockdown levels. Of the 38 percent of respondents from the new NIDS-CRAM survey reporting that children aged 0-6 in their households had attended ECD programmes before the lockdown in March, only 12 percent indicated that children had returned to these programmes by mid-July, well after programmes were allowed to reopen. Using these findings, we estimate that just 13 percent of children aged 0-6 were attending ECD programmes by mid-July to mid-August compared to 47 percent in 2018. The last time that ECD attendance rates were as low as this was in the early 2000s. At this point it is not yet clear what proportion of these declines are only temporary, or whether there will be a lasting impact on ECD enrolment in the country. This dramatic contraction in the ECD sector relates to prohibitive costs to reopening ‘safely’ imposed by the regulatory environment, coupled with shocks to the demand side for ECD programmes (both in terms of reduced household incomes and parent fears of children contracting COVID-19). When viewed from a broader socio-economic lens, the threat of ECD programme closures across the nation will have impacts beyond ECD operators to the lives of millions of children, millions of households and millions of adults who rely on these ECD services. A swift intervention by government is necessary to save this important sector and limit the ripple effect of programme closures on multiple layers of society.
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Mud Crab Fattening and Post-Harvest Handling Instruction Manual. Wildlife Conservation Society, 2021. http://dx.doi.org/10.19121/2021.report.39691.
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