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Japanese rice fish

May 02, 2024

"Medaka" redirects here. For the manga and anime series, see Medaka Box.

The Japanese rice fish (Oryzias latipes), also known as the medaka,[2] is a member of genus Oryzias (ricefish), the only genus in the subfamily Oryziinae. This small (up to about 3.6 cm or 1.4 in) native of Japan is a denizen of rice paddies, marshes, ponds, slow-moving streams and tide pools.[3][4] It is euryhaline, occurring in both brackish and freshwater.[3] It became popular as an aquarium fish because of its hardiness and pleasant coloration: its coloration varies from creamy-white to yellowish in the wild to white, creamy-yellow, or orange in aquarium-bred individuals. Bright yellow, red or green transgenic populations, similar to GloFish, have also been developed, but are banned from sale in the EU.[5] The medaka has been a popular pet since the 17th century in Japan.[6] After fertilization, the female carries her eggs attached anterior to the anal fin for a period before depositing them on plants or similar things.[5]

Japanese rice fish
Oryzias latipes
Scientific classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Beloniformes
Family: Adrianichthyidae
Genus: Oryzias
Species:
O. latipes
Binomial name
Oryzias latipes
Synonyms[2]
  • Poecilia latipes Temminck & Schlegel, 1846
  • Aplocheilus latipes (Temminck & Schlegel, 1846)

Ecology edit

Medaka live in small ponds, shallow rivers, and rice fields.[7] They can survive in a wide range of water temperatures (0–42 °C or 32–108 °F), but they prefer a water temperature of 15–28 °C (59–82 °F).[8] Since they eat juvenile mosquitoes and small plankton, they are known as a beneficial organism for humans. They produce 10–20 eggs per birth, and they can produce eggs every day in laboratory conditions. They are seasonal breeding animals and usually lay eggs between spring and summer.[9] They prefer to lay eggs around water grass and often prefer living in rice fields.[7] The egg usually requires 4–10 days to hatch.[10] They have an advanced renal function, which enables them to live in saltwater and brackish water.[11] The average life span of this species in the wild is estimated to be 2 years, though in laboratory conditions they can survive 3–5 years. They live in schools, and they can recognize the faces of other individual medaka.[12]

Taxonomy and range edit

 
A group in a shallow ditch, a typical habitat of the species (Katori, Japan)

As originally defined, O. latipes was native to much of east and mainland southeast Asia, but in recent decades most of these populations have been split off as separate species based on morphological (morphometrics and meristics) and genetic evidence.[4][13] This limits the native range of definite O. latipes to Japan: eastern and southern Honshu, Shikoku, Kyushu, and smaller southern islands in the country.[13] Formerly included in this species but now regarded as separate are O. sakaizumii in northwestern Honshu in Japan (locally, it hybridizes with O. latipes), and O. sinensis (Chinese rice fish) in much of China, west Korea and parts of mainland southeast Asia.[4][13][14] The taxonomic position of certain populations, including some in China, Laos and east Korea, is unclear and require further study.[4][13] It is possible that all these Chinese populations are part of O. sinensis, but the Laos specimens are relatively large, similar to O. latipes rather than the tiny O. sinensis.[4] The east Korean population is part of a clade with O. sakaizumii and O. latipes. Based on morphology it is closer to O. sakaizumii than O. latipes, but it may be an undescribed species.[13]

O. latipes has been introduced to Hokkaido in northern Japan (where ricefish are not native).[15] There are other reports of introductions around the world, but at least most of those in mainland Asia and Europe involve O. sinensis (Chinese rice fish).[15][16]

Origin of Southern and Northern Japanese populations edit

Phylogenetic analysis shows that the southern Japanese population was derived from that of the northern Kyushu area and spread into Honshu. On the other hand, the northern population was derived from a population from the Tajima-Tango region and spread alongside the Sea of Japan coast.[17] O. latipes is known to have nine sub-populations: East Japanese type, East Setouchi type, West Setouchi type, San'in type, Northern Kyushu type, Osumi Type, Ariake type, Satsuma type and Ryukyu type. These sub-populations have been mixed with each other due to artificial releasing and decreasing local genetic diversity.[citation needed]

Use in science edit

 
An orange aquarium variant (himedaka) achieved through selective breeding, photographed from above. Not to be confused with the brightly colored transgenic aquarium variants.

Oryzias latipes is a model organism and is extensively used in many areas of biological research, most notably in toxicology. Medaka have a short gestation period, and are reproductively prolific—characteristics that make them easy to rear in the laboratory. They can withstand cold and can be shipped easily. Nearly all aspects of the life cycle of medaka have been analyzed by researchers including sexual behavior, genetic inheritance of coloration, spawning habits, feeding, pathology, embryological development, ecology, etc.[18][19] It has a relatively small genome (~800 mega base pairs, half the size of the genome of another popular model fish, the zebrafish) as well as a generation time of 7 weeks (rather than 9 weeks for zebrafish) and hardier growth in a broad temperature range (6–40 °C or 43–104 °F).[20][21]

Transgenic medaka are relatively easy to produce. They have been genetically modified to secrete various human hormones, express promoter sequences from other fish, and to make antimicrobial proteins and a protein that makes the medaka glow fluorescent green, yellow or red.[5][22] There are also many mutations that show up in medaka at random, for example, a mutant strain that lacks scales, and one with extra-long fins. Haploid embryonic stem cell lines have been established.[23]

In space edit

O. latipes mating in space

O. latipes carries the distinction of having been the first vertebrate to mate in orbit.[24] The result of the mating was a brood of healthy fry, hatched on the Space Shuttle Columbia in 1994. O. latipes returned to space in 2012, launched aboard a Soyuz spacecraft Soyuz TMA-06M and housed in an aquarium aboard the International Space Station.[citation needed]

Inbreeding lines edit

The possibility of serial inbreeding facilitates genetic research due to reduction of heterozygous sites in the genome. In medaka it is relatively easy to establish inbred lines, unlike other model species like zebrafish and mice.[25] By 1979, researchers had generated 10 inbred strains.[26] These inbred lines made medaka a model species for scientific research in genetics.[27][28] In 2014, work began on generating 111 different inbred lines derived from a single population collected in the wild.[29]

Sex and reproduction edit

Medaka reproduce on a daily basis, which is an optimal trait for studying their reproductive biology. Researchers have studied HPG axis activities intensively in this species.[30][31] Moreover, the medaka is the first non-mammalian vertebrate species for which a sex-determination gene (DMY) has been identified,[32] their sex is reversible by sex steroid manipulation,[33] and they exhibit morphological sexual dimorphism between males and females. Furthermore, some methods such as ovariectomy[34] and altered light-dark cycles[35] have been developed to study the mechanism of reproduction in medaka.[citation needed]

Immunology edit

The discovery that T-lymphocytes home to the thymus in medaka has led to an understanding that this is not specific to mammalians but can be found in other vertebrates.[citation needed]

Skeletal Research edit

This species is increasingly used as a model in research relating to skeletal diseases in humans,[36] such as osteoporosis.

Conservation edit

Status edit

The medaka is listed as a least-concern species in the IUCN red list. The justification of this categorization is that this species is living in widespread habitat (755,000 km2) and is relatively abundant in its various habitats.[37] However, it is considered an endangered species by Japan's Ministry of the Environment.[38] Many local communities try to preserve wild medaka in Japan.[39][40][41]

Concerns edit

There are two major concerns about medaka conservation: habitat degradation and hybridization with domesticated medaka (himedaka). Due to modernization of rice fields and irrigation canals, optimal places for medaka reproduction are massively decreasing.[7] In addition, recent studies confirmed that himedaka have been introduced into many local regions by artificial release.[42] This will eliminate local genetic adaptations of each sub-population of medaka.[42][43] Furthermore, since himedaka have vivid orange body color, the hybrids will attract more predators and thus decrease the total medaka population.[44] In 2011, researchers discovered that almost 15% of wild-caught medaka in Nara had a himedaka-specific gene marker.[45] In addition to these concerns, invasive species like mosquitofish compete with medaka by sharing the same habitat. A study reported that over 70% of medaka had their tail fins injured by attacks from mosquitofish.[46] The damage at the anal fin will decrease medaka offspring by preventing courtship behavior.[47] In 2006, it was found that a transgenic line of medaka was brought to Japan from Taiwan for commercial purposes. This transgenic line had an introduced gene which expresses green fluorescence, making the body glow. Now, this transgenic line has been released into the wild and is causing genetic pollution.[48] There is no comprehensive study of population size of medaka, but the genomic analysis of one medaka sub-population indicates that their effective population size is around 25000–70000.[49]   

Medaka in Tokyo, Japan

Social importance in Japan edit

The medaka has been kept as a domesticated pet in Japan for centuries. In recent years the fish has gained further popularity, with some rarer breeds valued at over 1 million yen (approximately US$10,000)—though the most common varieties (like himedaka) can be purchased for around 50 yen per fish.[50] Currently, 456 commercial strains are documented and available for fishkeeping.[51] Medaka are not only kept as pets but also widely utilized in education; Japanese elementary school classes often raise medaka in order to give the students firsthand experience with caring for live organisms, as well as to foster more broad appreciation for animals' life cycles.[citation needed]

See also edit

  • Mummichog (Fundulus heteroclitus), first fish sent to space in 1973

References edit

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External links edit

 
Look up Medaka in Wiktionary, the free dictionary.
 
Wikimedia Commons has media related to:
Oryzias latipes (category)
 
Wikispecies has information related to Oryzias latipes.

May 02, 2024
japanese, rice, fish, medaka, redirects, here, manga, anime, series, medaka, oryzias, latipes, also, known, medaka, member, genus, oryzias, ricefish, only, genus, subfamily, oryziinae, this, small, about, native, japan, denizen, rice, paddies, marshes, ponds, . Medaka redirects here For the manga and anime series see Medaka Box The Japanese rice fish Oryzias latipes also known as the medaka 2 is a member of genus Oryzias ricefish the only genus in the subfamily Oryziinae This small up to about 3 6 cm or 1 4 in native of Japan is a denizen of rice paddies marshes ponds slow moving streams and tide pools 3 4 It is euryhaline occurring in both brackish and freshwater 3 It became popular as an aquarium fish because of its hardiness and pleasant coloration its coloration varies from creamy white to yellowish in the wild to white creamy yellow or orange in aquarium bred individuals Bright yellow red or green transgenic populations similar to GloFish have also been developed but are banned from sale in the EU 5 The medaka has been a popular pet since the 17th century in Japan 6 After fertilization the female carries her eggs attached anterior to the anal fin for a period before depositing them on plants or similar things 5 Japanese rice fish Oryzias latipes Conservation status Least Concern IUCN 3 1 1 Scientific classification Domain Eukaryota Kingdom Animalia Phylum Chordata Class Actinopterygii Order Beloniformes Family Adrianichthyidae Genus Oryzias Species O latipes Binomial name Oryzias latipes Temminck amp Schlegel 1846 Synonyms 2 Poecilia latipes Temminck amp Schlegel 1846 Aplocheilus latipes Temminck amp Schlegel 1846 Contents 1 Ecology 2 Taxonomy and range 2 1 Origin of Southern and Northern Japanese populations 3 Use in science 3 1 In space 3 2 Inbreeding lines 3 3 Sex and reproduction 3 4 Immunology 3 5 Skeletal Research 4 Conservation 4 1 Status 4 2 Concerns 5 Social importance in Japan 6 See also 7 References 8 External linksEcology editMedaka live in small ponds shallow rivers and rice fields 7 They can survive in a wide range of water temperatures 0 42 C or 32 108 F but they prefer a water temperature of 15 28 C 59 82 F 8 Since they eat juvenile mosquitoes and small plankton they are known as a beneficial organism for humans They produce 10 20 eggs per birth and they can produce eggs every day in laboratory conditions They are seasonal breeding animals and usually lay eggs between spring and summer 9 They prefer to lay eggs around water grass and often prefer living in rice fields 7 The egg usually requires 4 10 days to hatch 10 They have an advanced renal function which enables them to live in saltwater and brackish water 11 The average life span of this species in the wild is estimated to be 2 years though in laboratory conditions they can survive 3 5 years They live in schools and they can recognize the faces of other individual medaka 12 Taxonomy and range edit nbsp A group in a shallow ditch a typical habitat of the species Katori Japan As originally defined O latipes was native to much of east and mainland southeast Asia but in recent decades most of these populations have been split off as separate species based on morphological morphometrics and meristics and genetic evidence 4 13 This limits the native range of definite O latipes to Japan eastern and southern Honshu Shikoku Kyushu and smaller southern islands in the country 13 Formerly included in this species but now regarded as separate are O sakaizumii in northwestern Honshu in Japan locally it hybridizes with O latipes and O sinensis Chinese rice fish in much of China west Korea and parts of mainland southeast Asia 4 13 14 The taxonomic position of certain populations including some in China Laos and east Korea is unclear and require further study 4 13 It is possible that all these Chinese populations are part of O sinensis but the Laos specimens are relatively large similar to O latipes rather than the tiny O sinensis 4 The east Korean population is part of a clade with O sakaizumii and O latipes Based on morphology it is closer to O sakaizumii than O latipes but it may be an undescribed species 13 O latipes has been introduced to Hokkaido in northern Japan where ricefish are not native 15 There are other reports of introductions around the world but at least most of those in mainland Asia and Europe involve O sinensis Chinese rice fish 15 16 Origin of Southern and Northern Japanese populations edit Phylogenetic analysis shows that the southern Japanese population was derived from that of the northern Kyushu area and spread into Honshu On the other hand the northern population was derived from a population from the Tajima Tango region and spread alongside the Sea of Japan coast 17 O latipes is known to have nine sub populations East Japanese type East Setouchi type West Setouchi type San in type Northern Kyushu type Osumi Type Ariake type Satsuma type and Ryukyu type These sub populations have been mixed with each other due to artificial releasing and decreasing local genetic diversity citation needed Use in science edit nbsp An orange aquarium variant himedaka achieved through selective breeding photographed from above Not to be confused with the brightly colored transgenic aquarium variants Oryzias latipes is a model organism and is extensively used in many areas of biological research most notably in toxicology Medaka have a short gestation period and are reproductively prolific characteristics that make them easy to rear in the laboratory They can withstand cold and can be shipped easily Nearly all aspects of the life cycle of medaka have been analyzed by researchers including sexual behavior genetic inheritance of coloration spawning habits feeding pathology embryological development ecology etc 18 19 It has a relatively small genome 800 mega base pairs half the size of the genome of another popular model fish the zebrafish as well as a generation time of 7 weeks rather than 9 weeks for zebrafish and hardier growth in a broad temperature range 6 40 C or 43 104 F 20 21 Transgenic medaka are relatively easy to produce They have been genetically modified to secrete various human hormones express promoter sequences from other fish and to make antimicrobial proteins and a protein that makes the medaka glow fluorescent green yellow or red 5 22 There are also many mutations that show up in medaka at random for example a mutant strain that lacks scales and one with extra long fins Haploid embryonic stem cell lines have been established 23 In space edit source source source source source source O latipes mating in space O latipes carries the distinction of having been the first vertebrate to mate in orbit 24 The result of the mating was a brood of healthy fry hatched on the Space Shuttle Columbia in 1994 O latipes returned to space in 2012 launched aboard a Soyuz spacecraft Soyuz TMA 06M and housed in an aquarium aboard the International Space Station citation needed Inbreeding lines edit The possibility of serial inbreeding facilitates genetic research due to reduction of heterozygous sites in the genome In medaka it is relatively easy to establish inbred lines unlike other model species like zebrafish and mice 25 By 1979 researchers had generated 10 inbred strains 26 These inbred lines made medaka a model species for scientific research in genetics 27 28 In 2014 work began on generating 111 different inbred lines derived from a single population collected in the wild 29 Sex and reproduction edit Medaka reproduce on a daily basis which is an optimal trait for studying their reproductive biology Researchers have studied HPG axis activities intensively in this species 30 31 Moreover the medaka is the first non mammalian vertebrate species for which a sex determination gene DMY has been identified 32 their sex is reversible by sex steroid manipulation 33 and they exhibit morphological sexual dimorphism between males and females Furthermore some methods such as ovariectomy 34 and altered light dark cycles 35 have been developed to study the mechanism of reproduction in medaka citation needed Immunology edit The discovery that T lymphocytes home to the thymus in medaka has led to an understanding that this is not specific to mammalians but can be found in other vertebrates citation needed Skeletal Research edit This species is increasingly used as a model in research relating to skeletal diseases in humans 36 such as osteoporosis Conservation editStatus edit The medaka is listed as a least concern species in the IUCN red list The justification of this categorization is that this species is living in widespread habitat 755 000 km2 and is relatively abundant in its various habitats 37 However it is considered an endangered species by Japan s Ministry of the Environment 38 Many local communities try to preserve wild medaka in Japan 39 40 41 Concerns edit There are two major concerns about medaka conservation habitat degradation and hybridization with domesticated medaka himedaka Due to modernization of rice fields and irrigation canals optimal places for medaka reproduction are massively decreasing 7 In addition recent studies confirmed that himedaka have been introduced into many local regions by artificial release 42 This will eliminate local genetic adaptations of each sub population of medaka 42 43 Furthermore since himedaka have vivid orange body color the hybrids will attract more predators and thus decrease the total medaka population 44 In 2011 researchers discovered that almost 15 of wild caught medaka in Nara had a himedaka specific gene marker 45 In addition to these concerns invasive species like mosquitofish compete with medaka by sharing the same habitat A study reported that over 70 of medaka had their tail fins injured by attacks from mosquitofish 46 The damage at the anal fin will decrease medaka offspring by preventing courtship behavior 47 In 2006 it was found that a transgenic line of medaka was brought to Japan from Taiwan for commercial purposes This transgenic line had an introduced gene which expresses green fluorescence making the body glow Now this transgenic line has been released into the wild and is causing genetic pollution 48 There is no comprehensive study of population size of medaka but the genomic analysis of one medaka sub population indicates that their effective population size is around 25000 70000 49 source source source source source source source source source source Medaka in Tokyo JapanSocial importance in Japan editThe medaka has been kept as a domesticated pet in Japan for centuries In recent years the fish has gained further popularity with some rarer breeds valued at over 1 million yen approximately US 10 000 though the most common varieties like himedaka can be purchased for around 50 yen per fish 50 Currently 456 commercial strains are documented and available for fishkeeping 51 Medaka are not only kept as pets but also widely utilized in education Japanese elementary school classes often raise medaka in order to give the students firsthand experience with caring for live organisms as well as to foster more broad appreciation for animals life cycles citation needed See also edit nbsp Japan portal nbsp Fish portal Mummichog Fundulus heteroclitus first fish sent to space in 1973References edit Kanao S Taniguchi Y Watanabe K 2019 Oryzias latipes IUCN Red List of Threatened Species 2019 e T166979A1159322 doi 10 2305 IUCN UK 2019 2 RLTS T166979A1159322 en Retrieved 12 November 2021 a b Froese Rainer Pauly Daniel eds 2019 Oryzias latipes in FishBase April 2019 version a b Froese Rainer Pauly Daniel eds 2014 Oryzias latipes in FishBase April 2014 version a b c d e Parenti L R 2008 A phylogenetic analysis and taxonomic revision of ricefishes Oryzias and relatives Beloniformes Adrianichthyidae Zoological Journal of the Linnean Society 154 3 494 610 doi 10 1111 j 1096 3642 2008 00417 x a b c Oryzias latipes SeriouslyFish Retrieved 21 February 2017 Hellweg M August 2013 The Ricefish An Odd and Interesting Group TFH Magazine Retrieved 21 February 2017 a b c 牧人 小林 知尚 頼経 翔平 鈴木 彩美 清水 美香 小井土 優太郎 川口 洋一 早川 さやか 江口 弘文 横田 義和 山本 2012 屋外池における野生メダカ Oryzias latipes の繁殖行動 日本水産学会誌 78 5 922 933 doi 10 2331 suisan 78 922 Shima Akihiro Mitani Hiroshi 2004 07 01 Medaka as a research organism past present and future Mechanisms of Development 121 7 599 604 doi 10 1016 j mod 2004 03 011 ISSN 0925 4773 PMID 15210169 S2CID 397672 Hirshfield Michael F 1980 An Experimental Analysis of Reproductive Effort and Cost in the Japanese Medaka Oryzias Latipes Ecology 61 2 282 292 Bibcode 1980Ecol 61 282H doi 10 2307 1935187 ISSN 1939 9170 JSTOR 1935187 Iwamatsu Takashi 2004 07 01 Stages of normal development in the medaka Oryzias latipes Mechanisms of Development 121 7 605 618 doi 10 1016 j mod 2004 03 012 ISSN 0925 4773 PMID 15210170 S2CID 16570978 Sakamoto Tatsuya Kozaka Tomohiro Takahashi Akiyoshi Kawauchi Hiroshi Ando Masaaki 2001 02 15 Medaka Oryzias latipes as a model for hypoosmoregulation of euryhaline fishes Aquaculture 193 3 347 354 Bibcode 2001Aquac 193 347S doi 10 1016 S0044 8486 00 00471 3 ISSN 0044 8486 Wang Mu Yun Takeuchi Hideaki 2017 07 11 Tsao Doris Y ed Individual recognition and the face inversion effect in medaka fish Oryzias latipes eLife 6 e24728 doi 10 7554 eLife 24728 ISSN 2050 084X PMC 5505697 PMID 28693720 a b c d e Asai T Senou H Hosoya K 2011 Oryzias sakaizumii a new ricefish from northern Japan Teleostei Adrianichthyidae Ichthyol Explor Freshwaters 22 4 289 299 ISSN 0936 9902 Parenti L 2012 Oryzias sinensis IUCN Red List of Threatened Species 2012 e T181312A1720540 doi 10 2305 IUCN UK 2012 1 RLTS T181312A1720540 en a b Oryzias latipes Invasive species of Japan National Institute for Environmental Studies Japan Retrieved 20 February 2017 Kottelat M Freyhof J 2007 Handbook of European freshwater fishes Publications Kottelat Cornol Switzerland ISBN 978 2 8399 0298 4 Katsumura Takafumi Oda Shoji Mitani Hiroshi Oota Hiroki 2019 01 01 Medaka Population Genome Structure and Demographic History Described via Genotyping by Sequencing G3 Genes Genomes Genetics 9 1 217 228 doi 10 1534 g3 118 200779 ISSN 2160 1836 PMC 6325896 PMID 30482798 Leroi Armand Marie 2003 Mutants On Genetic Variety and the Human Body New York Viking Penguin Publishing ISBN 0 670 03110 0 Major topic Oryzias free full text articles in National Library of Medicine Oryzias latipes medaka as a model organism taxonomy facts development stages bibliography at GeoChemBio Medaka Oryzias latipes Genome Browser Gateway Tanaka M Kinoshita M Kobayashi D Nagahama Y 2001 Establishment of medaka Oryzias latipes transgenic lines with the expression of green fluorescent protein fluorescence exclusively in germ cells a useful model to monitor germ cells in a live vertebrate Proc Natl Acad Sci USA 98 5 2544 9 Bibcode 2001PNAS 98 2544T doi 10 1073 pnas 041315498 PMC 30174 PMID 11226275 Yi Meisheng Hong Ni Hong Yunhan 2009 Generation of Medaka Fish Haploid Embryonic Stem Cells Science 326 5951 430 433 Bibcode 2009Sci 326 430Y doi 10 1126 science 1175151 PMID 19833967 S2CID 7505131 Medaka aboard Columbia Archived from the original on 2009 03 26 Retrieved 2006 07 16 Hilgers Leon Schwarzer Julia 2019 The untapped potential of medaka and its wild relatives eLife 8 doi 10 7554 eLife 46994 ISSN 2050 084X PMC 6615862 PMID 31287418 NBRP Medaka shigen nig ac jp Retrieved 2019 10 07 Kasahara Masahiro Naruse Kiyoshi Sasaki Shin Nakatani Yoichiro Qu Wei Ahsan Budrul Yamada Tomoyuki Nagayasu Yukinobu Doi Koichiro Kasai Yasuhiro Jindo Tomoko June 2007 The medaka draft genome and insights into vertebrate genome evolution Nature 447 7145 714 719 Bibcode 2007Natur 447 714K doi 10 1038 nature05846 ISSN 1476 4687 PMID 17554307 Kimura Tetsuaki Shimada Atsuko Sakai Noriyoshi Mitani Hiroshi Naruse Kiyoshi Takeda Hiroyuki Inoko Hidetoshi Tamiya Gen Shinya Minori 2007 12 01 Genetic Analysis of Craniofacial Traits in the Medaka Genetics 177 4 2379 2388 doi 10 1534 genetics 106 068460 ISSN 0016 6731 PMC 2219511 PMID 18073435 Kirchmaier Stephan Naruse Kiyoshi Wittbrodt Joachim Loosli Felix 2015 04 01 The Genomic and Genetic Toolbox of the Teleost Medaka Oryzias latipes Genetics 199 4 905 918 doi 10 1534 genetics 114 173849 ISSN 0016 6731 PMC 4391551 PMID 25855651 Karigo Tomomi Kanda Shinji Takahashi Akiko Abe Hideki Okubo Kataaki Oka Yoshitaka 2012 07 01 Time of Day Dependent Changes in GnRH1 Neuronal Activities and Gonadotropin mRNA Expression in a Daily Spawning Fish Medaka Endocrinology 153 7 3394 3404 doi 10 1210 en 2011 2022 ISSN 0013 7227 PMID 22544888 Kanda Shinji 2018 11 27 Evolution of the regulatory mechanisms for the hypothalamic pituitary gonadal axis in vertebrates hypothesis from a comparative view General and Comparative Endocrinology 284 113075 doi 10 1016 j ygcen 2018 11 014 ISSN 0016 6480 PMID 30500374 S2CID 54468539 Matsuda Masaru Nagahama Yoshitaka Shinomiya Ai Sato Tadashi Matsuda Chika Kobayashi Tohru Morrey Craig E Shibata Naoki Asakawa Shuichi Shimizu Nobuyoshi Hori Hiroshi May 2002 DMY is a Y specific DM domain gene required for male development in the medaka fish Nature 417 6888 559 563 Bibcode 2002Natur 417 559M doi 10 1038 nature751 ISSN 1476 4687 PMID 12037570 S2CID 4363239 Scholz S Gutzeit H O 2000 10 01 17 a ethinylestradiol affects reproduction sexual differentiation and aromatase gene expression of the medaka Oryzias latipes Aquatic Toxicology 50 4 363 373 Bibcode 2000AqTox 50 363S doi 10 1016 S0166 445X 00 00090 4 ISSN 0166 445X PMID 10967398 Kanda Shinji Akazome Yasuhisa Matsunaga Takuya Yamamoto Naoyuki Yamada Shunji Tsukamura Hiroko Maeda Kei ichiro Oka Yoshitaka 2008 05 01 Identification of KiSS 1 Product Kisspeptin and Steroid Sensitive Sexually Dimorphic Kisspeptin Neurons in Medaka Oryzias latipes Endocrinology 149 5 2467 2476 doi 10 1210 en 2007 1503 ISSN 0013 7227 PMID 18202129 Weber D N Spieler R E 1987 06 01 Effects of the light dark cycle and scheduled feeding on behavioral and reproductive rhythms of the cyprinodont fish Medaka Oryzias latipes Experientia 43 6 621 624 doi 10 1007 BF02126355 ISSN 1420 9071 PMID 3595795 S2CID 11727260 Di Biagio Claudia Dellacqua Zachary Martini Arianna Huysseune Ann Scardi Michele Witten Paul Eckhard Boglione Clara 2022 06 30 A Baseline for Skeletal Investigations in Medaka Oryzias latipes The Effects of Rearing Density on the Postcranial Phenotype Frontiers in Endocrinology 13 doi 10 3389 fendo 2022 893699 ISSN 1664 2392 PMC 9281570 PMID 35846331 The IUCN Red List of Threatened Species IUCN Red List of Threatened Species Retrieved 2019 11 29 unknown url Takehana Yusuke Nagai Naoko Matsuda Masaru Tsuchiya Kimiyuki Sakaizumi Mitsuru October 2003 Geographic Variation and Diversity of the Cytochrome b Gene in Japanese Wild Populations of Medaka Oryzias latipes Zoological Science 20 10 1279 1291 doi 10 2108 zsj 20 1279 ISSN 0289 0003 PMID 14569151 S2CID 22958328 東京めだか を守っています 東京ズーネット www tokyo zoo net Retrieved 2019 11 29 追跡取材 進行中の 三浦メダカ 保全活動をレポート はまれぽ com 神奈川県の地域情報サイト はまれぽ com Retrieved 2019 11 29 和歌山市におけるのメダカの現在の生息状況 kodomo123 jp Retrieved 2019 11 29 a b Nakao Ryohei Iguchi Yuka Koyama Naoto Nakai Koji Kitagawa Tadao 2017 01 01 Current status of genetic disturbances in wild medaka populations Oryzias latipes species complex in Japan Ichthyological Research 64 1 116 119 Bibcode 2017IchtR 64 116N doi 10 1007 s10228 016 0528 5 ISSN 1616 3915 S2CID 44688469 直人 小山 幹大 森 宏施 中井 忠生 北川 2011 市販されているメダカのミトコンドリアdna 遺伝子構成 魚類学雑誌 58 1 81 86 doi 10 11369 jji 58 81 Nakao Ryohei Kitagawa Tadao 2015 Differences in the behavior and ecology of wild type medaka Oryzias latipes complex and an orange commercial variety himedaka Journal of Experimental Zoology Part A Ecological Genetics and Physiology 323 6 349 358 Bibcode 2015JEZA 323 349N doi 10 1002 jez 1916 ISSN 1932 5231 PMID 26054930 宏施 中井 遼平 中尾 昌司 深町 直人 小山 忠生 北川 2011 ヒメダカ体色原因遺伝子マーカーによる奈良県大和川水系のメダカ集団の解析 魚類学雑誌 58 2 189 193 doi 10 11369 jji 58 189 優秋 田代 康則 上月 陽一 佐藤 仁士 村上 2005 外来種カダヤシによるメダカへの影響と保全策に関する一考察 日本生態学会大会講演要旨集 ESJ52 814 doi 10 14848 esj ESJ52 0 814 0 珠央 伊藤 右介 小関 靖章 新妻 2006 メダカOryzias latipesにおける雄の鰭の損傷による産卵数および受精率の低下 野生生物保護 10 1 2 1 7 doi 10 20798 wildlifeconsjp 10 1 2 1 環境省 未承認の遺伝子組換えメダカの回収のお願いについて www env go jp Retrieved 2019 11 29 Spivakov Mikhail Auer Thomas O Peravali Ravindra Dunham Ian Dolle Dirk Fujiyama Asao Toyoda Atsushi Aizu Tomoyuki Minakuchi Yohei Loosli Felix Naruse Kiyoshi 2014 03 01 Genomic and Phenotypic Characterization of a Wild Medaka Population Towards the Establishment of an Isogenic Population Genetic Resource in Fish G3 Genes Genomes Genetics 4 3 433 445 doi 10 1534 g3 113 008722 ISSN 2160 1836 PMC 3962483 PMID 24408034 100万円の値がついた 高級メダカ とは 人気急上昇中 希少なメダカを一挙公開 ラグジュアリー体験の入り口メディア in Japanese Retrieved 2019 11 29 改良メダカ年表 めだかの館 改良メダカ年表 めだかの館 in Japanese Retrieved 2019 11 29 External links edit nbsp Look up Medaka in Wiktionary the free dictionary nbsp Wikimedia Commons has media related to Oryzias latipes category nbsp Wikispecies has information related to Oryzias latipes View the oryLat2 genome assembly in the UCSC Genome Browser Medaka genome in Ensembl Medaka Fish Farm Retrieved from https en wikipedia org w index php title Japanese rice fish amp oldid 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