Initiation of gynogenesis in Oreochromis niloticus following heterologous fertilization

Fertilization of tilapia ( Oreochromis niloticus ) eggs with heterologous sperm from carp ( Cyprinus carpio ), and from some other eyprinids resulted in higher levels of haploid gynogenetic development than in unfertilized eggs. Normal and irradiated carp sperm achieved similar rates of activation of tilapia eggs, but lower rates than those achieved by irradiated tilapia sperm. Diploidy in gynogenetic eggs fertilized with carp sperm was restored using pressure shocks and resulted in the development of healthy tilapia gynogens.