Growth of triploid and diploid bighead carp, Hypophthalmichthys nobilis.
Second-year triploid and diploid bighead carp were studied in a 189- to 190-day trial. Bighead carp were was grown separately and together with channel catfish (Ictalurus punctatus) and grass carp (Ctenopharyngodon idella). When cultured separately, diploids were longer (526 vs. 499 mm) and heavier (1645 vs. 1427 g) than triploids at harvest, but the differences were not significant. When cultured communally, the diploids were significantly longer (519 vs. 485 mm) and heavier (1621 vs. 1321 g) than triploids. Ploidy of all bighead carp was determined after fish were harvested; 7.9% of the presumed triploids that were stocked separately were diploids.