Study On The Application Of Animal Model BLUP And DFREML For Genetic Evaluation In Japanese Flounder (Paralichthys Olivaceus)

Samples derived from the research center in BeiDaiHe based in Chinese academy of fishery sciences, based on wild Japanese Flounder to build family. The fish were recorded when they were 185 day, 235 day, 345day, 455 day and 505 day. The study analyzed the major factors influencing the growth trait of Japanese Flounder, compared different models and estimated variance components and genetics parameters of total length, body length, head length, caudal peduncle length, postortital length, body depth, caudal peduncle depth, body weight and condition factor utilizing Derivative-Free Restricted Maximum Likelihood(DFREML) and animal model Best Linear Unbiased Prediction (BLUP).The fixed effects, the permanent environment effects and the fixed effects, the permanent environment effects and the animal genetic effects were calculated. Animal were ranked according to their estimated breeding value (EBV)to provide information for selection. The results showed as following:Pool, year, season, family and test-day significantly affected almost all growth traits.Genetic parameters were estimated with single-trait, multiple-trait and repeatability animal models. Total length, body length, head length, caudal peduncle length, postorbital length, body depth, caudal peduncle depth, body weight and condition factor showed low to moderate heritability estimates ranging from 0.22 to 0.30, from 0.23 to 0.30, from 0.23 to 0.29, from 0.23 to 0.29, from 0.26 to 0.38, from 0.22 to 0.34, from 0.20 to 0.29, from 0.19 to 0.31 and from 0.22 to 0.43 by single-trait animal model, respectively. Total length, body length, head length, caudal peduncle length, postortital length, body depth, caudal peduncle depth, body weight and condition factor exhibited low to moderate heritability by multiple-trait animal model, the heritability ranging between 0.26 to 0.31, between 0.23 to 0.35, between 0.29 to 0.38, between 0.26 to 0.38, between 0.26 to 0.38, between 0.19 to 0.28, between 0.14 to 0.29, between 0.20 to 0.35 and between 0.11 to 0.36, respectively. Heritability was estimated with repeatability animal model for total length, body length, head length, caudal peduncle length, postortital length, body depth, caudal peduncle depth, body weight and condition factor were 0.3, 0.29, 0.32, 0.28, 0.35, 0.32, 0.25, 0.34 and 0.20, respectively. Significant phenotypic positive correlations were found among eight growth traits including total length, body length, head length, caudal peduncle length, postortital length, body depth, caudal peduncle depth and body weight. Significant negative correlations were found at 185, 235 and 345 test-day between condition factor to body weight, the correlations coefficients is -0.349, -0.123 and -0.282, respectively. Insignificant positive correlations and significant positive correlations were found at 455 and 505 test-day whose correlations coefficients are 0.074 and 0.167. The genetic correlations trend of the traits was the same to phenotypic correlations.In comparison of different model, repeatability was the optimal model.The ranks of all kinds of one-trait estimated breeding values were basely same to comprehensive estimated breeding value. And all the genetic evaluation methods had significant correlations.