Comparative analysis of liver transcriptomes associated with hypoxia tolerance in the gynogenetic blunt snout bream

Gynogenetic diploid was induced in red crucian carp (RCC) (Carassius auratus Red Variety) eggs using UV-irradiated spermatozoa from blunt snout bream (B) (Megalabrama amblycephala) or from mirror carp (C) (Cyprinus carpio. L). Spermatozoa were genetically inactivated by an appropriate UV dosage, and then the maternal DNA was duplicated with cold shock at 0–4°C. When using the spermatozoa of B, the fertilization rate, hatching rate and survival at first feeding were 52.6 ± 3.0 %, 23.6 ± 4.1 % and 15.7 ± 3.4 % respectively, and the survival at first feeding was significantly higher than that (11.3 ± 2.2%) when using the spermatozoa of C(Cypripnus carpio. L). According to the morphological characteristics, the chromosome number and the degree of gonadal development, gynogenetic RCC could be distinguished from the control hybrids of RCC ♀ × B♂. The individuals with red body color, 100 chromosomes and normal gonadal development were syccessful gyogenetic RCC, while the individuals with 124 or 148 chro...

Induction of gynogenesis in red crucian carp using Spermatozoa of blunt snout bream

The first case of induced gynogenesis in Neotropical fishes using the yellowtail tetra (Astyanax altiparanae) as a model organism

Telophase of the first cleavage is the key stage for optimally inducing mitotic gynogenesis in rice field eel (Monopterus albus)

Sperm quality of spontaneously occurring gynogenetic males in the yellowtail tetra Astyanax altiparanae

Induction of diploid gynogenesis by heat shock treatment in silver barb (Barbonymus gonionotus)

This study was dealt with induction of diploid meiotic and mitotic gynogenesis in Barbonymus gonionotus through cold shock treatment for production of monosex all-female population. For inhibition of paternal inheritance, sperm DNA was denatured by exposing cell suspension containing 8×108 ml-1 to UV at 196 μWcm-2 for 1.5 min. After fertilization of eggs using uv-treated sperm, meiotic diploidization was done by cold shock treatment at 2 °C for 1 min applied 1.5 min of post-fertilization that produced 44.23±0.62% meiotic gynogens. Mitotic diploidization was done by the same cold shock treatment applied after 27.5 min of fertilization that produced 36.70±0.63% mitotic gynogens. Ploidy status of all the progenies was evaluated by karyotyping. The karyotype analysis revealed 23 (N) chromosomes in haploids, and 46 (2N) chromosomes in meiotic and mitotic gynogens and controls. Sexing of fish showed nearly all-female, ranging from 98.28 to 100% and 96.43 to 100% female in the meiotic and mitotic gynogens respectively. The sex ratio in the control group was nearly 1:1. DNA microsatellite analysis revealed that the meiotic gynogenetic offspring possessed two alleles the same as their mother and the mitotic gynogenetic offspring possessed any of the two alleles of their mother and became homozygous. No meiotic and mitotic gynogens have inheritance of paternal alleles. The control offspring shared alleles from both male and female parents. Thus, the study confirmed the production of meiotic and mitotic gynogens of silver barb through cold shock treatment and they could be converted into sex-reversed males (XX) by masculinizing hormone treatment for production of monosex all-female population.

Rafiul Islam

Papers

Induction of diploid gynogenesis by heat shock treatment in silver barb (Barbonymus gonionotus)

Induction of meiotic and mitotic gynogenesis in silver barb (Barbonymus gonionotus) through cold shock treatment