This disclosure describes exemplary embodiments of a method of creating a YY animal broodstock, preferably in a single generation, wherein the broodstock includes only sperm-producing YY males and egg-producing YY males, the method comprising the steps of: (a) creating YY males via androgenesis； (b) exposing selected ones of the YY males created in step (a) to a feminizing hormone； and (c) identifying sperm-producing YY males and egg-producing YY males from among the YY males created in steps (a) and (b). In other embodiments, the method further comprises: (d) repeating steps (a) through (c) N times in order to produce N unrelated families of sperm-producing YY males and egg-producing YY males； and (e) cross-breeding various ones of the unrelated families produced in step (d) in order to produce a genetically-diverse YY progeny. In some embodiments, N may be about 60.
