Growth of eight Pacific abalone families at three temperatures

Growth rates, measured as shell length and body weight daily growth, were studied in the eight families of Pacific abalone, Haliotis discus hannai Ino, reared at 12, 16 and 20℃ for 40 d respectively. The results show that J1Rh family grew the best at 12℃, with growth rates of (32.88±4.66) μm/d and (5.24±1.84) mg/d. C₁Jm family had the highest growth rates of (58.00±2.00) μm/d and (9.71±1.21) mg/d at 16℃. J₁Jm family ranked the first at 20℃, with growth rates of (66.00±1.76) μm/d and (10.99±0.34) mg/d.RjRh family had the slowest growth rates at all three temperatures. Shell length growth rates were 18.25, 33.00 and 43.13 μm/d respectively, while body weight growth rates were 2.47, 2.56 and 4.75 mg/d respectively. Both temperature and family had significant effect on growth rates (P<0.05). At 16 and 20℃, maternal effects on growth rates were not significant (P>0.05), but paternal effects on growth rates were significant (P<0.05). Results of this study indicate genetic difference among the families and importance of selecting male breeders in the commercial hatchery.