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88-400: Myxozoa ( etymology : Greek : μύξα myxa "slime" or "mucus" + thematic vowel o + ζῷον zoon "animal") is a subphylum of aquatic cnidarian animals – all obligate parasites . It contains the smallest animals ever known to have lived. Over 2,180 species have been described and some estimates have suggested at least 30,000 undiscovered species. Many have a two-host lifecycle, involving

176-487: A descendant , derivative or derived from an etymon (but see below). Cognates or lexical cognates are sets of words that have been inherited in direct descent from an etymological ancestor in a common parent language. Doublets or etymological twins or twinlings (or possibly triplets, and so forth) are specifically cognates within the same language. Although they have the same etymological root, they tend to have different phonological forms, and to have entered

264-581: A fish and an annelid worm or a bryozoan . The average size of a myxosporean spore usually ranges from 10 μm to 20 μm, whereas that of a malacosporean (a subclade of the Myxozoa) spore can be up to 2 mm. Myxozoans can live in both freshwater and marine habitats. Myxozoans are highly derived cnidarians that have undergone dramatic evolution from a free swimming, self-sufficient jellyfish -like creature into their current form of obligate parasites composed of very few cells – sometimes only

352-500: A Welsh philologist living in India , who in 1782 observed the genetic relationship between Sanskrit , Greek and Latin . Jones published his The Sanscrit Language in 1786, laying the foundation for the field of Indo-European linguistics . The study of etymology in Germanic philology was introduced by Rasmus Christian Rask in the early 19th century and elevated to a high standard with

440-505: A derivative with the meaning "to mark with blood"). Semantic change may also occur. For example, the English word bead originally meant "prayer". It acquired its modern meaning through the practice of counting the recitation of prayers by using beads. The search for meaningful origins for familiar or strange words is far older than the modern understanding of linguistic evolution and the relationships of languages, which began no earlier than

528-461: A growing demand for high-quality protein, encouraged aquaculturists to domesticate other marine species. At the outset of modern aquaculture, many were optimistic that a " Blue Revolution " could take place in aquaculture, just as the Green Revolution of the 20th century had revolutionized agriculture. Although land animals had long been domesticated, most seafood species were still caught from

616-422: A large scale and are most often taken in the wild. In 2016, aquaculture was the source of 96.5 percent by volume of the total 31.2 million tonnes of wild-collected and cultivated aquatic plants combined. Global production of farmed aquatic plants, overwhelmingly dominated by seaweeds, grew in output volume from 13.5 million tonnes in 1995 to just over 30 million tonnes in 2016. Seaweed farming or kelp farming

704-629: A large toll in human lives. Most major human diseases originated in domesticated animals, including diseases such as smallpox and diphtheria , that like most infectious diseases, move to humans from animals. No human pathogens of comparable virulence have yet emerged from marine species. Biological control methods to manage parasites are already being used, such as cleaner fish (e.g. lumpsuckers and wrasse) to control sea lice populations in salmon farming. Models are being used to help with spatial planning and siting of fish farms in order to minimize impact. The decline in wild fish stocks has increased

792-635: A line of ancient grammarians of Sanskrit who lived several centuries earlier like Sakatayana of whom very little is known. The earliest of attested etymologies can be found in Vedic literature in the philosophical explanations of the Brahmanas , Aranyakas , and Upanishads . The analyses of Sanskrit grammar done by the previously mentioned linguists involved extensive studies on the etymology (called Nirukta or Vyutpatti in Sanskrit) of Sanskrit words, because

880-463: A long written history , etymologists make use of texts, particularly texts about the language itself, to gather knowledge about how words were used during earlier periods, how they developed in meaning and form , or when and how they entered the language. Etymologists also apply the methods of comparative linguistics to reconstruct information about forms that are too old for any direct information to be available. By analyzing related languages with

968-399: A single cell . As myxozoans evolved into microscopic parasites, they lost many genes responsible for multicellular development, coordination, cell–cell communication , and even, in some cases, aerobic respiration . The genomes of some myxozoans are now among the smallest genomes of any known animal species. Myxozoans are endoparasitic animals exhibiting complex life cycles that, in most of

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1056-513: A technique known as the comparative method , linguists can make inferences about their shared parent language and its vocabulary. In this way, word roots in many European languages, for example, can be traced back to the origin of the Indo-European language family . Even though etymological research originated from the philological tradition, much current etymological research is done on language families where little or no early documentation

1144-418: A total output which is double that of the rest of the world put together. However, there are some historical issues with the accuracy of China's returns. In 2001, scientists Reg Watson and Daniel Pauly expressed concerns that China was over reporting its catch from wild fisheries in the 1990s. They said that made it appear that the global catch since 1988 was increasing annually by 300,000 tonnes, whereas it

1232-405: A worm-like parasite of bryozoans up to 2 mm in length, is a myxozoan initially appeared to strengthen the case for a bilaterian origin, as the body plan is superficially similar. Nevertheless, closer examination reveals that Buddenbrockia 's longitudinal symmetry is not twofold, but fourfold, casting doubt on this hypothesis . Further testing resolved the genetic conundrum by sourcing

1320-532: Is an especially important economic activity in China. Between 1980 and 1997, the Chinese Bureau of Fisheries reports, aquaculture harvests grew at an annual rate of 16.7%, jumping from 1.9 million tonnes to nearly 23 million tonnes. In 2005, China accounted for 70% of world production. Aquaculture is also currently one of the fastest-growing areas of food production in the U.S. About 90% of all U.S. shrimp consumption

1408-476: Is available, such as Uralic and Austronesian . The word etymology is derived from the Ancient Greek word ἐτυμολογία ([ἐτυμολογία] Error: {{Transliteration}}: transliteration text not Latin script ( help ) ), itself from ἔτυμον ([ἔτυμον] Error: {{Transliteration}}: transliteration text not Latin script ( help ) ), meaning ' true sense or sense of a truth ' , and the suffix -logia , denoting '

1496-694: Is farmed and imported. In recent years, salmon aquaculture has become a major export in southern Chile, especially in Puerto Montt , Chile's fastest-growing city. A United Nations report titled The State of the World Fisheries and Aquaculture released in May 2014 maintained fisheries and aquaculture support the livelihoods of some 60 million people in Asia and Africa. FAO estimates that in 2016, overall, women accounted for nearly 14 percent of all people directly engaged in

1584-752: Is farmed for agar ; the rest are eaten after limited processing. Seaweeds are different from mangroves and seagrasses , as they are photosynthetic algal organisms and are non-flowering. The largest seaweed-producing countries as of 2022 are China (58.62%) and Indonesia (28.6%); followed by South Korea (5.09%) and the Philippines (4.19%). Other notable producers include North Korea (1.6%), Japan (1.15%), Malaysia (0.53%), Zanzibar ( Tanzania , 0.5%), and Chile (0.3%). Seaweed farming has frequently been developed to improve economic conditions and to reduce fishing pressure. The Food and Agriculture Organization (FAO) reported that world production in 2019

1672-527: Is generally perceived as benign or even beneficial. Depending on the species and local conditions, bivalve molluscs are either grown on the beach, on longlines, or suspended from rafts and harvested by hand or by dredging. In May 2017 a Belgian consortium installed the first of two trial mussel farms on a wind farm in the North Sea . Abalone farming began in the late 1950s and early 1960s in Japan and China. Since

1760-494: Is highly probable that future developments in this field will rely on microorganisms, but greater funding and further research is needed to overcome the lack of knowledge in this field. Microalgae , also referred to as phytoplankton , microphytes , or planktonic algae , constitute the majority of cultivated algae . Macroalgae commonly known as seaweed also have many commercial and industrial uses, but due to their size and specific requirements, they are not easily cultivated on

1848-484: Is not easily derived due to lack of data. Another recent issue following the banning in 2008 of organotins by the International Maritime Organization is the need to find environmentally friendly, but still effective, compounds with antifouling effects. Many new natural compounds are discovered every year, but producing them on a large enough scale for commercial purposes is almost impossible. It

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1936-574: Is produced in Asia, in particular in China and Thailand. The other 25% is produced mainly in Latin America, where Brazil is the largest producer. Thailand is the largest exporter. Shrimp farming has changed from its traditional, small-scale form in Southeast Asia into a global industry. Technological advances have led to ever higher densities per unit area, and broodstock is shipped worldwide. Virtually all farmed shrimp are penaeids (i.e., shrimp of

2024-414: Is said, the way of light. Etymology in the modern sense emerged in the late 18th-century European academia, within the context of the wider " Age of Enlightenment ", although preceded by 17th century pioneers such as Marcus Zuerius van Boxhorn , Gerardus Vossius , Stephen Skinner , Elisha Coles , and William Wotton . The first known systematic attempt to prove the relationship between two languages on

2112-462: Is seeded with young abalone from an onshore hatchery. The abalone feed on seaweed that has grown naturally on the habitats, with the ecosystem enrichment of the bay also resulting in growing numbers of dhufish, pink snapper, wrasse, and Samson fish, among other species. Brad Adams, from the company, has emphasised the similarity to wild abalone and the difference from shore-based aquaculture. "We're not aquaculture, we're ranching, because once they're in

2200-475: Is such, she is gracious in beholding, she spreadeth over all without lying down, she passeth in going right without crooking by right long line; and it is without dilation of tarrying, and therefore it is showed the blessed Lucy hath beauty of virginity without any corruption; essence of charity without disordinate love; rightful going and devotion to God, without squaring out of the way; right long line by continual work without negligence of slothful tarrying. In Lucy

2288-420: Is the harvesting of wild fish . Aquaculture is also a practice used for restoring and rehabilitating marine and freshwater ecosystems. Mariculture , commonly known as marine farming, is aquaculture in seawater habitats and lagoons, as opposed to freshwater aquaculture. Pisciculture is a type of aquaculture that consists of fish farming to obtain fish products as food . Aquaculture can also be defined as

2376-492: Is the practice of cultivating and harvesting seaweed . In its simplest form farmers gather from natural beds, while at the other extreme farmers fully control the crop's life cycle . The seven most cultivated taxa are Eucheuma spp., Kappaphycus alvarezii , Gracilaria spp., Saccharina japonica , Undaria pinnatifida , Pyropia spp., and Sargassum fusiforme . Eucheuma and K. alvarezii are attractive for carrageenan (a gelling agent ); Gracilaria

2464-523: Is the same: one or two sporoplasts , which are the real infectious agent, surrounded by a layer of flattened cells called valve cells , which can secrete a layer protective coating and form float appendages . Integrated into the layer of valve cells are two to four specialized capsulogenic cells (in a few cases, one or even 15), each carrying a polar capsule containing coiled polar filaments , an extrudable organelle used for recognition, contact and infiltration. Myxospores are ingested by annelids, in which

2552-904: The German Dictionary of the Brothers Grimm . The successes of the comparative approach culminated in the Neogrammarian school of the late 19th century. Still in the 19th century, German philosopher Friedrich Nietzsche used etymological strategies (principally and most famously in On the Genealogy of Morals , but also elsewhere) to argue that moral values have definite historical (specifically, cultural) origins where modulations in meaning regarding certain concepts (such as "good" and "evil") show how these ideas had changed over time—according to which value-system appropriated them. This strategy gained popularity in

2640-665: The Aquaculture Stewardship Council with the Dutch Sustainable Trade Initiative to manage the global standards and certification programs. After trials in 2012, a commercial "sea ranch" was set up in Flinders Bay , Western Australia, to raise abalone. The ranch is based on an artificial reef made up of 5000 (As of April 2016 ) separate concrete units called abitats (abalone habitats). The 900 kg abitats can host 400 abalone each. The reef

2728-406: The ecosystem . Some traditional polyculture systems may, in fact, incorporate a greater diversity of species, occupying several niches , as extensive cultures (low intensity, low management) within the same pond. A working IMTA system can result in greater total production based on mutual benefits to the co-cultured species and improved ecosystem health , even if the production of individual species

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2816-506: The family Penaeidae ), and just two species of shrimp, the Pacific white shrimp and the giant tiger prawn , account for about 80% of all farmed shrimp. These industrial monocultures are very susceptible to disease, which has decimated shrimp populations across entire regions. Increasing ecological problems, repeated disease outbreaks, and pressure and criticism from both nongovernmental organizations and consumer countries led to changes in

2904-1560: The polypodiozoa , shared their last common ancestor with medusazoans about 600 million years ago, during the Ediacaran period. Myxozoan taxonomy has undergone great and important changes in its levels of generic, family and suborder classification. Fiala et al. (2015) proposed a new classification based on spores. Genus: Buddenbrockia, Tetracapsuloides Genus: Sphaeromyxa Genus: Myxidium, Zschokkella, Enteromyxum, Sigmomyxa, Soricimyxum, Cystodiscus Genus: Ortholinea, Neomyxobolus, Cardimyxobolus, Triangula, Kentmoseria Genus: Sinuolinea, Myxodavisia, Myxoproteus, Bipteria, Paramyxoproteus, Neobipteria, Schulmania, Noblea, Latyspora Genus: Fabespora Genus: Ceratomyxa, Meglitschia, Ellipsomyxa, Ceratonova Genus: Sphaerospora, Wardia, Palliatus Genus: Myxobilatus, Acauda, Hoferellus Genus: Chloromyxum, Caudomyxum, Agarella Genus: Coccomyxa, Auerbachia, Globospora Genus: Alatospora, Pseudalatospora, Renispora Genus: Parvicapsula, Neoparvicapsula, Gadimyxa Genus: Myxobolus, Spirosuturia, Unicauda, Dicauda, Phlogospora, Laterocaudata, Henneguya, Hennegoides, Tetrauronema, Thelohanellus, Neothelohanellus, Neohenneguya, Trigonosporus Genus: Trilospora, Unicapsula Genus: Kudoa Genus: Octospina   incertae sedis :       Trilosporoides       . . .      Etymology For languages with

2992-434: The rearing process to enhance production, such as regular stocking , feeding , protection from predators, etc. Farming also implies individual or corporate ownership of the stock being cultivated." The reported output from global aquaculture operations in 2019 was over 120 million tonnes valued at US$ 274 billion, by 2022, it had risen to 130.9 million tonnes, valued at USD 312.8 billion. However, there are issues with

3080-558: The 18th century. From Antiquity through the 17th century, from Pāṇini to Pindar to Sir Thomas Browne , etymology had been a form of witty wordplay, in which the supposed origins of words were creatively imagined to satisfy contemporary requirements; for example, the Greek poet Pindar (born in approximately 522 BCE) employed inventive etymologies to flatter his patrons. Plutarch employed etymologies insecurely based on fancied resemblances in sounds . Isidore of Seville 's Etymologiae

3168-432: The 1980s and 1990s. In 2012, the total world production of fisheries was 158 million tonnes , of which aquaculture contributed 66.6 million tonnes, about 42%. The growth rate of worldwide aquaculture has been sustained and rapid, averaging about 8% per year for over 30 years, while the take from wild fisheries has been essentially flat for the last decade. The aquaculture market reached $ 86 billion in 2009. Aquaculture

3256-669: The 20th century, and philosophers, such as Jacques Derrida , have used etymologies to indicate former meanings of words to de-center the "violent hierarchies" of Western philosophy . Aquaculture Aquaculture (less commonly spelled aquiculture ), also known as aquafarming , is the controlled cultivation ("farming") of aquatic organisms such as fish , crustaceans , mollusks , algae and other organisms of value such as aquatic plants (e.g. lotus ). Aquaculture involves cultivating freshwater , brackish water , and saltwater populations under controlled or semi-natural conditions and can be contrasted with commercial fishing , which

3344-928: The Agriculture Ministry's Bureau of Fisheries, as saying that China's figures were "basically correct". However, the FAO accepted there were issues with the reliability of China's statistical returns, and for a period treated data from China, including the aquaculture data, apart from the rest of the world. Mariculture is the cultivation of marine organisms in seawater , variously in sheltered coastal waters ("inshore"), open ocean ("offshore"), and on land ("onshore"). Farmed species include algae (from microalgae (such as phytoplankton ) to macroalgae (such as seaweed ); shellfish (such as shrimp ), lobster , oysters ), and clams , and marine finfish . Channel catfish ( Ictalurus punctatus ), hard clams ( Mercenaria mercenaria ) and Atlantic salmon ( Salmo salar ) are prominent in

3432-471: The Caribbean (2%). The contribution of aquaculture to the global production of capture fisheries and aquaculture combined has risen continuously, reaching 46.8 percent in 2016, up from 25.7 percent in 2000. With 5.8 percent annual growth rate during the period 2001–2016, aquaculture continues to grow faster than other major food production sectors, but it no longer has the high annual growth rates experienced in

3520-412: The U.S. mariculture. Mariculture may consist of raising the organisms on or in artificial enclosures such as in floating netted enclosures for salmon, and on racks or in floating cages for oysters. In the case of enclosed salmon, they are fed by the operators; oysters on racks filter feed on naturally available food. Abalone have been farmed on an artificial reef consuming seaweed which grows naturally on

3608-517: The ancient Indians considered sound and speech itself to be sacred and, for them, the words of the sacred Vedas contained deep encoding of the mysteries of the soul and God. One of the earliest philosophical texts of the Classical Greek period to address etymology was the Socratic dialogue Cratylus ( c.  360 BCE ) by Plato . During much of the dialogue, Socrates makes guesses as to

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3696-454: The basis of similarity of grammar and lexicon was made in 1770 by the Hungarian, János Sajnovics , when he attempted to demonstrate the relationship between Sami and Hungarian (work that was later extended to the whole Finno-Ugric language family in 1799 by his fellow countryman, Samuel Gyarmathi ). The origin of modern historical linguistics is often traced to Sir William Jones ,

3784-516: The breeding, growing, and harvesting of fish and other aquatic plants, also known as farming in water. It is an environmental source of food and commercial products that help to improve healthier habitats and are used to reconstruct the population of endangered aquatic species. Technology has increased the growth of fish in coastal marine waters and open oceans due to the increased demand for seafood. Aquaculture can be conducted in completely artificial facilities built on land (onshore aquaculture), as in

3872-434: The case of fish tank , ponds , aquaponics or raceways , where the living conditions rely on human control such as water quality (oxygen), feed, temperature. Alternatively, they can be conducted on well-sheltered shallow waters nearshore of a body of water (inshore aquaculture), where the cultivated species are subjected to relatively more naturalistic environments; or on fenced/enclosed sections of open water away from

3960-462: The clade as severely modified members of the phylum Cnidaria , with medusozoans as their closest relatives. Similarities between myxozoan polar capsules and cnidarian nematocysts had been drawn for a long time, but were generally assumed to be the result of convergent evolution . Taxonomists now recognize the outdated subgroup Actinosporea as a life-cycle phase of Myxosporea . Molecular clocks suggest that myxozoans and their closest relatives,

4048-423: The commercial fish industry, largely as a result of aquaculture bringing new species into contact with myxosporeans to which they had not been previously exposed, and to which they are highly susceptible. The economic impact of such parasites can be severe, especially where prevalence rates are high; they may also have a severe impact on wild fish stocks. The diseases caused by myxosporeas in cultured fish with

4136-548: The cultivation of ornamental fish . Particular methods include aquaponics and integrated multi-trophic aquaculture , both of which integrate fish farming and aquatic plant farming. The FAO describes aquaculture as one of the industries most directly affected by climate change and its impacts. Some forms of aquaculture have negative impacts on the environment, such as through nutrient pollution or disease transfer to wild populations. Harvest stagnation in wild fisheries and overexploitation of popular marine species, combined with

4224-439: The decade to 2007. Given the long-term importance of agriculture, to date, only 0.08% of known land plant species and 0.0002% of known land animal species have been domesticated, compared with 0.17% of known marine plant species and 0.13% of known marine animal species. Domestication typically involves about a decade of scientific research. Domesticating aquatic species involves fewer risks to humans than do land animals, which took

4312-446: The demand for farmed fish. However, finding alternative sources of protein and oil for fish feed is necessary so the aquaculture industry can grow sustainably; otherwise, it represents a great risk for the over-exploitation of forage fish. Aquaculture production now exceeds capture fishery production and together the relative GDP contribution has ranged from 0.01 to 10%. Singling out aquaculture's relative contribution to GDP, however,

4400-706: The developmental lifecycle of the main species, the giant river prawn . The global annual production of freshwater prawns (excluding crayfish and crabs ) in 2007 was about 460,000 tonnes , exceeding 1.86 billion dollars. Additionally, China produced about 370,000 tonnes of Chinese river crab . In addition astaciculture is the freshwater farming of crayfish (mostly in the US, Australia, and Europe). Aquacultured shellfish include various oyster , mussel , and clam species. These bivalves are filter and/or deposit feeders, which rely on ambient primary production rather than inputs of fish or other feed. As such, shellfish aquaculture

4488-475: The discovery that myxozoans are cnidarians. These cnidocysts fire tubules as in other cnidarians; some inject substances into the host. However, the tubules lack hooks or barbs, and in some species are more elastic than in other cnidarians. Myxozoans have secondarily lost epithelial structures, a nervous system , gut , and cilia . Most lack muscles , though these are retained in some members of malacosporea . Those who have lost their muscles move around inside

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4576-418: The documented cases, involve an intermediate host , usually a fish, but in rare cases amphibians, reptiles, birds, and mammals; and a definitive host, usually an annelid or an ectoproct . Only about 100 life cycles have been resolved and it is suspected that there may be some exclusively terrestrial. The mechanism of infection occurs through valve spores that have many forms, but their main morphology

4664-477: The final site of infection, they produce mature spores within mono- or di-sporic pseudoplasmodia , or poly-sporic plasmodia . Relationships between myxosporeans and their hosts are often highly evolved and do not usually result in severe diseases of the natural host. Infection in fish hosts can be extremely long-lasting, potentially persisting for the lifetime of the host. However, an increasing number of myxosporeans have become pathogens with significant impact to

4752-530: The first three previously identified discrepant HOX genes ( Myx1-3 ) to the bryozoan Cristatella mucedo and the fourth ( Myx4 ) to northern pike , the respective hosts of the two corresponding Myxozoa samples. This explained the confusion: the original experiments had used samples contaminated by tissue from host organisms, leading to false positives for a position among the Bilateria. More careful cloning of 50 coding genes from Buddenbrockia firmly established

4840-416: The fisheries and aquaculture primary sector. In 2021, global fish production reached 182 million tonnes, with approximately equal amounts coming from capture (91.2 million tonnes) and aquaculture (90.9 million tonnes). Aquaculture has experienced rapid growth in recent decades, increasing almost sevenfold from 1990 to 2021. China overwhelmingly dominates the world in reported aquaculture output, reporting

4928-426: The form of an etymology. The Sanskrit linguists and grammarians of ancient India were the first to make a comprehensive analysis of linguistics and etymology. The study of Sanskrit etymology has provided Western scholars with the basis of historical linguistics and modern etymology. Four of the most famous Sanskrit linguists are: These linguists were not the earliest Sanskrit grammarians, however. They followed

5016-418: The gods, who have power and command overall. Others make the word refer to exceptions of impossible cases; the priests were to perform all the duties possible; if anything lays beyond their power, the exception was not to be cavilled. The most common opinion is the most absurd, which derives this word from pons, and assigns the priests the title of bridge-makers. The sacrifices performed on the bridge were amongst

5104-553: The group Sporozoa . As their distinct nature became clear through 18S ribosomal DNA (rDNA) sequencing, they were relocated in the metazoa . Detailed classification within the metazoa was however long hindered by conflicting rDNA evidence: although 18S rDNA suggested an affinity with Cnidaria , other rDNA sampled, and the HOX genes of two species, were more similar to those of the Bilateria . The discovery that Buddenbrockia plumatellae ,

5192-446: The host using other forms of locomotion, such as the use of filopodia , spore valve contractions, amoeboid movements, and rapidly creating and reabsorbing folds on the cell membrane. Myxozoans do not undergo embryogenesis during development and have lost true gametes . Instead, they reproduce via multicellular spores. These spores contain the polar capsules, which are not typically present in somatic cells. Centrioles are not involved in

5280-451: The incorporation of species from different trophic or nutritional levels in the same system. This is one potential distinction from the age-old practice of aquatic polyculture , which could simply be the co-culture of different fish species from the same trophic level. In this case, these organisms may all share the same biological and chemical processes, with few synergistic benefits, which could potentially lead to significant shifts in

5368-480: The industry in the late 1990s and generally stronger regulations. In 1999, governments, industry representatives, and environmental organizations initiated a program aimed at developing and promoting more sustainable farming practices through the Seafood Watch program. Freshwater prawn farming shares many characteristics with, including many problems with, marine shrimp farming. Unique problems are introduced by

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5456-415: The industry. Sea ranching involves raising fish in a hatchery for a brief time and then releasing them into marine waters for further development, whereupon the fish are recaptured when they have matured. Commercial shrimp farming began in the 1970s, and production grew steeply thereafter. Global production reached more than 1.6 million tonnes in 2003, worth about US$ 9 billion. About 75% of farmed shrimp

5544-493: The language through different routes. A root is the source of related words within a single language (no language barrier is crossed). Similar to the distinction between etymon and root , a nuanced distinction can sometimes be made between a descendant and a derivative . A derivative is one of the words which have their source in a root word, and were at some time created from the root word using morphological constructs such as suffixes, prefixes, and slight changes to

5632-536: The market. In 2009, researchers in Australia managed for the first time to coax southern bluefin tuna to breed in landlocked tanks. Southern bluefin tuna are also caught in the wild and fattened in grow-out sea cages in southern Spencer Gulf , South Australia . A similar process is used in the salmon-farming section of this industry; juveniles are taken from hatcheries and a variety of methods are used to aid them in their maturation. For example, as stated above, some of

5720-541: The mid-1990s, this industry has become increasingly successful. Overfishing and poaching have reduced wild populations to the extent that farmed abalone now supplies most abalone meat. Sustainably farmed molluscs can be certified by Seafood Watch and other organizations, including the World Wildlife Fund (WWF). WWF initiated the "Aquaculture Dialogues" in 2004 to develop measurable and performance-based standards for responsibly farmed seafood. In 2009, WWF co-founded

5808-434: The most important fish species in the industry, salmon, can be grown using a cage system. This is done by having netted cages, preferably in open water that has a strong flow, and feeding the salmon a special food mixture that aids their growth. This process allows for year-round growth of the fish, thus a higher harvest during the correct seasons. An additional method, known sometimes as sea ranching, has also been used within

5896-515: The most sacred and ancient, and the keeping and repairing of the bridge attached, like any other public sacred office, to the priesthood. Isidore of Seville compiled a volume of etymologies to illuminate the triumph of religion. Each saint's legend in Jacobus de Varagine 's Legenda Aurea begins with an etymological discourse on the saint's name: Lucy is said of light, and light is beauty in beholding, after that S. Ambrose saith: The nature of light

5984-661: The most significant economic impact worldwide are proliferative kidney disease (PKD) caused by the malacosporean T. bryosalmonae , and whirling disease , caused by a myxosporean M. cerebralis ; both diseases affect salmon . Enteromyxosis is caused by E. leei in cultured marine sparids , while proliferative gill disease (or “hamburger disease”) is caused by H. ictaluri in catfish and S. renicola infections occur in common carp . Myxozoans are very small animals, typically 10–300  μm in length. Like other cnidarians they possess cnidocysts , which were referred to as "polar capsules" before

6072-476: The nuclear division of myxozoans. Cell division by binary fission is rare, and cells divide instead via endogeny . In 2020, the myxozoan Henneguya salminicola was found to lack a mitochondrial genome , and thus be incapable of aerobic respiration ; it was the first animal to be positively identified as such. Its actual metabolism is currently unknown. Myxozoans were originally considered to be protozoans , and were included among other non-motile forms in

6160-407: The origin of newly emerged words is often more or less transparent, it tends to become obscured through time due to sound change or semantic change. Due to sound change , it is not readily obvious that the English word set is related to the word sit (the former is originally a causative formation of the latter). It is even less obvious that bless is related to blood (the former was originally

6248-411: The origins of many words, including the names of the gods. In his Odes Pindar spins complimentary etymologies to flatter his patrons. Plutarch ( Life of Numa Pompilius ) spins an etymology for pontifex , while explicitly dismissing the obvious, and actual "bridge-builder": The priests, called Pontifices.... have the name of Pontifices from potens , powerful because they attend the service of

6336-435: The origins of words, some of which are: Etymological theory recognizes that words originate through a limited number of basic mechanisms, the most important of which are language change , borrowing (i.e., the adoption of " loanwords " from other languages); word formation such as derivation and compounding ; and onomatopoeia and sound symbolism (i.e., the creation of imitative words such as "click" or "grunt"). While

6424-416: The polar filaments extrude to anchor the spore to the gut epithelium . Opening of the shell valves allows the sporoplasms to penetrate into the epithelium. Subsequently, the parasite undergoes reproduction and development in the gut tissue, and finally produces usually eight actinosporean spore stages (actinospores) within a pansporocyst . After mature actinospores are released from their hosts they float in

6512-571: The reef units. Integrated multi-trophic aquaculture (IMTA) is a practice in which the byproducts (wastes) from one species are recycled to become inputs ( fertilizers , food ) for another. Fed aquaculture (for example, fish , shrimp ) is combined with inorganic extractive and organic extractive (for example, shellfish ) aquaculture to create balanced systems for environmental sustainability (biomitigation), economic stability (product diversification and risk reduction) and social acceptability (better management practices). "Multi-trophic" refers to

6600-488: The reliability of the reported figures. Further, in current aquaculture practice, products from several kilograms of wild fish are used to produce one kilogram of a piscivorous fish like salmon . Plant and insect-based feeds are also being developed to help reduce wild fish been used for aquaculture feed. Particular kinds of aquaculture include fish farming , shrimp farming , oyster farming , mariculture, pisciculture , algaculture (such as seaweed farming ), and

6688-576: The reported output from global aquaculture operations was over 120 million tonnes valued at US$ 274 billion and by 2022 it had reached 130.9 million tonnes, valued at USD 312.8 billion. For the first time, aquaculture surpassed capture fisheries in aquatic animal production with 94.4 million tonnes, representing 51 percent of the world total and a record 57 percent of the production destined for human consumption. In 2022 most aquaculture workers were in Asia (95%), followed by Africa (3%) and Latin America and

6776-525: The shore (offshore aquaculture), where the species are either cultured in cages, racks or bags and are exposed to more diverse natural conditions such as water currents (such as ocean currents ), diel vertical migration and nutrient cycles . According to the Food and Agriculture Organization (FAO), aquaculture "is understood to mean the farming of aquatic organisms including fish, molluscs, crustaceans and aquatic plants. Farming implies some form of intervention in

6864-465: The study or logic of ' . The etymon refers to the predicate (i.e. stem or root ) from which a later word or morpheme derives. For example, the Latin word candidus , which means ' white ' , is the etymon of English candid . Relationships are often less transparent, however. English place names such as Winchester , Gloucester , Tadcaster share in different modern forms a suffixed etymon that

6952-452: The total and 53 percent if non-food uses (including reduction to fishmeal and fish oil) are excluded. With capture fishery production relatively static since the late 1980s, aquaculture has been responsible for the continuing growth in the supply of fish for human consumption. Global aquaculture production (including aquatic plants) in 2016 was 110.2 million tonnes, with the first-sale value estimated at US$ 244 billion. Three years later, in 2019

7040-411: The vowels or to the consonants of the root word. For example unhappy , happily , and unhappily are all derivatives of the root word happy . The terms root and derivative are used in the analysis of morphological derivation within a language in studies that are not concerned with historical linguistics and that do not cross the language barrier. Etymologists apply a number of methods to study

7128-416: The water column. Upon contact with skin or gills of fish, sporoplasms penetrate through the epithelium, followed by development of the myxosporean stage. Myxosporean trophozoites are characterized by cell-in-cell state, where the secondary (daughter) cells develop in the mother (primary) cells. The presporogonic stages multiply, migrate via nervous or circulatory systems, and develop into sporogonic stages. At

7216-595: The water they look after themselves." Other groups include aquatic reptiles, amphibians, and miscellaneous invertebrates, such as echinoderms and jellyfish . They are separately graphed at the top right of this section, since they do not contribute enough volume to show clearly on the main graph. Commercially harvested echinoderms include sea cucumbers and sea urchins . In China, sea cucumbers are farmed in artificial ponds as large as 400 hectares (1,000 acres). Global fish production peaked at about 171 million tonnes in 2016, with aquaculture representing 47 percent of

7304-520: The wild for recreational fishing or to supplement a species' natural numbers is generally referred to as a fish hatchery . Worldwide, the most important fish species used in fish farming are, in order, carp , salmon , tilapia , and catfish . In the Mediterranean, young bluefin tuna are netted at sea and towed slowly towards the shore. They are then interned in offshore pens (sometimes made from floating HDPE pipe) where they are further grown for

7392-411: The wild. Concerned about the impact of growing demand for seafood on the world's oceans, prominent ocean explorer Jacques Cousteau wrote in 1973: "With earth's burgeoning human populations to feed, we must turn to the sea with new understanding and new technology." About 430 (97%) of the species cultured as of 2007 were domesticated during the 20th and 21st centuries, of which an estimated 106 came in

7480-459: Was an encyclopedic tracing of "first things" that remained uncritically in use in Europe until the sixteenth century. Etymologicum genuinum is a grammatical encyclopedia edited at Constantinople in the ninth century, one of several similar Byzantine works. The thirteenth-century Legenda Aurea , as written by Jacobus de Varagine , begins each vita of a saint with a fanciful excursus in

7568-518: Was once meaningful, Latin castrum ' fort ' . Reflex is the name given to a descendant word in a daughter language, descended from an earlier language. For example, Modern English heat is the reflex of the Old English hǣtu. Rarely, this word is used in reverse, and the 'reflex' is actually the root word rather than the descendant word. However, this usage is usually filled by the term etymon instead. A reflex will sometimes be described simply as

7656-454: Was over 35 million tonnes. North America produced some 23,000 tonnes of wet seaweed. Alaska, Maine, France, and Norway each more than doubled their seaweed production since 2018 . As of 2019, seaweed represented 30% of marine aquaculture. The farming of fish is the most common form of aquaculture. It involves raising fish commercially in tanks, fish ponds , or ocean enclosures, usually for food. A facility that releases juvenile fish into

7744-432: Was really shrinking annually by 350,000 tonnes. Watson and Pauly suggested this may have been related to Chinese policies where state entities that monitored the economy were also tasked with increasing output. Also, until more recently, the promotion of Chinese officials was based on production increases from their own areas. China disputed this claim. The official Xinhua News Agency quoted Yang Jian, director general of

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