Principles of Genetics and Breeding

5.1.8.3 Reproduction

In fish hybrids, sexual maturation may be affected in several ways. Some hybrids present a normal maturation of both sexes, allowing production of F₂ or back crosses.

• For instance Oncorhynchusketa x O. nerka hybrids in salmonids, Oreochromics mossambicus x O. hornorum hybrids in cichlids.
• Some others only exhibit atrophic gonads with a few sexual cells at an early stage of gametogenesis: this is the “gonadic” sterility, as in “tiger” hybrids in salmonids.