Carotenoids were introduced into the egg yolk of the medaka by either injection or feeding. Carotenoids for injection were dissolved in either olive oil, a mixture of olive oil and castor oil or Tween 80. Capsanthin, lutein and canthaxanthin were readily transferred from the yolk to the larval xanth
The production of cloned fish in the medaka (Oryzias latipes)
β Scribed by Naruse, K. ;Ijiri, K. ;Shima, A. ;Egami, N.
- Publisher
- John Wiley and Sons
- Year
- 1985
- Tongue
- English
- Weight
- 579 KB
- Volume
- 236
- Category
- Article
- ISSN
- 0022-104X
No coin nor oath required. For personal study only.
β¦ Synopsis
The measurement of cellular DNA content by DNA microfluorometry revealed that medaka embryos that were fertilized with normal sperm and exposed to heat shock (41Β°C for 3 min) or hydrostatic pressure (700 kg/cm2 for 10 min) at 85-95 min after insemination were tetraploid. Embryos fertilized with normal sperm and exposed to heat shock (41 "C for 2 min at 2-3 min after insemination) were triploid. These results suggest that heat shock or hydrostatic pressure at 85-95 min after insemination arrests the first cleavage, while heat shock at 2-3 min after insemination arrests the second meiotic division.
Medaka clones have been produced by the following method: Eggs from orange-red or variegated variety were activated by UV-irradiated, genetically impotent sperm of wild-type fish (UV sperm). The haploid eggs obtained were diploidized by preventing the first cleavage with heat shock or hydrostatic pressure to produce homozygous females. Each of the two homozygous females was mated with vasectomized male in isotonic balanced salt solution to collect unfertilized eggs. The collected eggs were activated with UV sperm and converted from haploid to diploid by arrest of the second meiotic division with heat shock. Hatched fry of each homozygous diploid (all females) were fed with a methyltestosterone-containing diet (40 pg/gm diet) to produce sex-reversed males, which were mated with brood females. and thus two cloned lines were obtained.
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## Abstract A cDNA for furin was cloned from the ovary of the medaka, __Oryzias latipes__, by a combination of cDNA library screening, 5';βrapid amplification of cDNA ends (RACE), and 3'β RACE. The cDNA sequence codes for a protein of 814 amino acid residues highly homologous to other vertebrate fu
The origin of the oocyte-like cells (testis-ova) induced by the administration of estradiol in the testis of the fish, Oryzias latipes, was examined by light and electron microscopy. A small number of testis-ova at the zygotene stage was seen on the sixth day after the beginning of treatment with es