Figure 1From: New approach for fish breeding by chemical mutagenesis: establishment of TILLING method in fugu (Takifugu rubripes) with ENU mutagenesisScheme design of the ENU mutagenesis in fugu. A) The number of ENU treatments in fugu. The number and timing of ENU injections was examined. ENU (concentration: 70Â mg/kg body weight of fugu) was injected 3 times at weekly intervals into the intraperitoneal of fugu males at the stage before spermiation. B) Treatment with various ENU concentrations, and timing of gonadotrophin (HCG/SPH) treatment and sperm collection. Founder fish were treated with three ENU concentrations (7, 70, 120Â mg/kg body weight of fugu) at the stage before spermiation. As a control, the fish were treated with buffer (0Â mg/kg body weight of fugu) instead of ENU. HCG/SPH was injected into the fugu intramuscularly at 2 or 3Â weeks after the last ENU injection. Sperm was collected at 3, 5, and 6Â weeks after the last ENU injection.Back to article page