Generating gynogenetic common carp (Cyprinus carpio L.) by Gama ray

We investigated the generation of gynogenetic common carp (Cyprinus carpio L.) during 1989-1990. After selection of suitable breeders containing special transferrin marker in breeding season, we applied ionizing radiation (60 Co gamma ray) for genetic inactivation of spermatozoa of the fish. We found that in the exposure of the sperm to a range 80-120 Krad irradiation, 100 Krad gave the best results. Application of various cold and heat shocks to the eggs at different time intervals after addition of water to the mixture of milk and eggs generated diploid gynogenetic fish. Cold and hot shock treatments generated significantly different gynogenetic fish (7% and 2. 5% respectively). The optimum shock treatment was found to be 5 minutes after fertilization in 0 C lasting 50 minutes. For each treatment, 100 fish fingerlings were subjected to electrophoresis which showed the mitotic diploid progenies were all-maternal inherited with BB genotype.