Estimation of genetic parameters for growth traits in cultured Takifugu obscurus

Abstract

The aim of this study was to estimate the genetic parameters of growth performance in Takifugu obscurus. Heritability estimates and genetic correlations were obtained for body weight (BW), body length (BL), total length (TL), chest measurement (CM) and trunk length (TKL). The individuals were measured at the age of 6 and 12 months, and they originated from a nested mating design experimental set up. Estimates were made on data from 50 full-sib and 25 half-sib families. The results showed heritability values of 0.280 for BW6, 0.235 for BL6, 0.217 for TL6, 0.246 for CM6, 0.207 for TKL6, 0.240 for BW12, 0.221 for BL12, 0.198 for TL12, 0.230 for CM12 and 0.187 for TKL12. The ranges of genetic correlation estimated within the 6 and the 12 months of age were 0.733–0.971 and 0.155–0.994, respectively, and the range of genetic correlation associated with growth traits between the two ages was 0.097–0.726. The results indicated that genetic improvement for faster growth rate or increased body mass in cultured Takifugu obscures was effective. The selection method for traits with moderate heritability was flexible. Considering that these growth traits did not reach a high level of heritability, family selection should be adopted. Also, as there was a high genetic correlation between BW, BL, TL and CM, these four traits could be improved simultaneously through selective breeding. In addition, CM could be used as a morphological marker of rapid growth for Takifugu obscurus.