title: Induced gynogenesis in grass carp (Ctenopharyngodon idellus) using irradiated sperm of allotetraploid hybrids.
abstract: Grass carp (Ctenopharyngodon idellus) eggs were activated by UV-irradiated diploid sperm of allotetraploid hybrids derived from red crucian carp (♀) × common carp (♂) and then duplicated by cold shock in 4-6°C water for 10-12 min. Different cold shock initiation times resulted in two types of diploid gynogenetic grass carp: meiotic gynogenetic (meiG) and mitotic gynogenetic (mitG). Over a 5-year period, a total of 17,170 meiG and 1,080 mitG fry were produced and 6,862 meiG and 372 mitG grass carp survived. The gynogenetic fish were confirmed by morphological characteristics, chromosome examination, and microsatellite DNA analysis. The morphological traits of the gynogenetic grass carp were similar to those of wild diploid grass carp. Normal gynogenetic fish were identified as diploid with 48 chromosomes by chromosomal metaphases examination, while nonviable abnormal embryos were detected as haploid with 24 chromosomes. Microsatellite DNA analysis indicated that after one generation of gynogenesis, the genetic purity of meiG and mitG grass carp was significantly increased over that of wild grass carp. In addition, both meiG and mitG grass carp groups were 100% female, and 88% of these showed normal ovary development. Thus, the sex determination mechanism in female grass carp was homogamety. The ability to establish pure all-female groups of meiG and mitG grass carp should be a valuable contribution to both fish genetics and grass carp breeding.
authors.affiliation: Key Laboratory of Protein Chemistry and Fish Developmental Biology of the Education Ministry of China, College of Life Sciences, Hunan Normal University, Changsha, 410081, People's Republic of China.
authors.forename: Hong
authors.initials: H
authors.lastname: Zhang
authors.forename: ShaoJun
authors.initials: S
authors.lastname: Liu
authors.forename: Chun
authors.initials: C
authors.lastname: Zhang
authors.forename: Min
authors.initials: M
authors.lastname: Tao
authors.forename: LiangYue
authors.initials: L
authors.lastname: Peng
authors.forename: CuiPing
authors.initials: C
authors.lastname: You
authors.forename: Jun
authors.initials: J
authors.lastname: Xiao
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhou
authors.forename: GongJian
authors.initials: G
authors.lastname: Zhou
authors.forename: KaiKun
authors.initials: K
authors.lastname: Luo
authors.forename: Yun
authors.initials: Y
authors.lastname: Liu
mesh_terms: D000818:Animals; D002347:Carps / Q000196:embryology* / Q000235:genetics*; D002874:Chromosome Mapping; D003080:Cold Temperature; D003433:Crosses, Genetic; D005260:Female; D008297:Male; D008540:Meiosis; D018895:Microsatellite Repeats; D008938:Mitosis; D013094:Spermatozoa / Q000528:radiation effects*; D057891:Tetraploidy; D013997:Time Factors; D014466:Ultraviolet Rays