Development of Pacific abalone (Haliotis discus hannai Ino) broodstock: initial characterization of early growth traits of F₁ progeny.

摘要

Families of Pacific abalone (Haliotis discus hannai Ino) were initiated from fertilized gametes from broodstock taken from Japan and China. Three wild stocks from Hokkaido (Hkd), Iwate (Iwt), and Miyagi (Myg), Japan, and a local farmed stock (Zzd) at Zhangzidao Island, Dalian, China, were collected and conditioned at Zhangzidao Island during the winter in 2010. In 2011, 95 full-sib families generated by a single-mating method within each stock were tested for growth performance under a hatchery and sea-based culture system for a 1-y period. Progeny from the 4 stocks were reared in separated tanks under identical conditions until 5 mo posthatch, then 4,925 juveniles were tagged and evaluated in a growth trial that consisted of 2 replicate large pools. Growth data of juvenile abalone at the age of 1 y posthatch were collected and used to investigate differences among the stock in daily growth rate. Stock effect and full-sib effect on abalone daily growth rate from tagging to the end of the 1-y culture period were both significant. Variation among individuals within the full-sib families is comparable with the variation among stock. Top-ranked full-sib families based on 1-y growth performance were from varying Pacific abalone stock. The implications of the results is that, when comparing the performance of different H. discus hannai stock or initiating a selective breeding program for H. discus hannai, it is important to test many breeders from each stock. In terms of growth performance, top-ranked candidate F1 families from varying stock may be crossbred to generate F2 families if potential positive growth heterosis occurs.