title: Production of androgenetic diploid loach by cold-shock of eggs fertilized with diploid sperm.
abstract: Diploid androgenotes were produced without egg irradiation in the loach, Misgurnus anguillicaudatus. Eggs of wild-type diploid females were fertilized with diploid sperm of a neo-tetraploid male and then cold-shock treated at 3 °C (range, ±0.5 °C) for 30 minutes just after fertilization to eliminate the female nucleus. After hatching, ploidy status of the hatched larvae was analyzed by flow cytometry, which revealed putative diploid androgenotes as well as larvae possessing other ploidies. Five independent microsatellite DNA markers were genotyped to confirm all-male inheritance of the resultant diploid larvae. The mean ± SD yield rate of diploid androgenetic larvae to total eggs used was 12.29 ± 3.25% in the cold-shock group and 22.23 ± 13.42% in the UV-irradiated group (P > 0.05). No diploid androgenetic larvae were detected in the intact control group. To our knowledge, this is the first report demonstrating successful induction of diploid androgenotes without egg irradiation in fish.
authors.affiliation: Faculty and Graduate School of Fisheries Sciences, Hokkaido University, Hakodate, Japan. jilunhou@hotmail.com
authors.forename: Jilun
authors.initials: J
authors.lastname: Hou
authors.forename: Takafumi
authors.initials: T
authors.lastname: Fujimoto
authors.forename: Etsuro
authors.initials: E
authors.lastname: Yamaha
authors.forename: Katsutoshi
authors.initials: K
authors.lastname: Arai
mesh_terms: D000818:Animals; D003080:Cold Temperature; D003531:Cypriniformes / Q000502:physiology*; D004171:Diploidy; D005260:Female; D005306:Fertilization / Q000502:physiology / Q000528:radiation effects; D005838:Genotype; D008297:Male; D019849:Sex Determination Processes / Q000528:radiation effects; D012743:Sex Preselection / Q000379:methods / Q000662:veterinary*; D013094:Spermatozoa / Q000502:physiology* / Q000528:radiation effects; D057891:Tetraploidy; D014466:Ultraviolet Rays; D015053:Zygote / Q000502:physiology* / Q000528:radiation effects