WU Shui-qing1, LUO Hui-yu1, ZHANG Zhe1, ZHENG Le-yun1*, WANG Quan-yang2, LIN Ke-bing1, GE Hui1, JIANG Shuang-cheng1, QIU Feng-yan3
1.Key Laboratory of Cultivation and High-value Utilization of Marine Organisms in Fujian Province, Fisheries Research Institute of Fujian Province, Xiamen 361013, China; 2.Dongshan County Oceanic and Fishery Administration, Zhangzhou 363400, China; 3.Xiamen Xiaodeng Aquatic Science and Technology Company Limited, Xiamen 361000, China
Abstract: Body weight(Y), total length (X1), body length (X2), head length (X3), body depth (X4), head length behind of eyes(X5), trunk length (X6), caudal peduncle length (X7), and caudal peduncle depth (X8) were measured in 339 samples of Yunlong grouper Epinephelusmoara♀×E.lanceolatus♂ with 4, 9 and 15 month old age collected from a hatchery in Xiamen, Fujian province, and were analyzed by principal component and path analysis to probe into the relevance of various phenotypic traits of Yunlong grouper and the corresponding body weight. The optimal regression equation of Yunlong grouper was shown to be expressed as Y4=-47.887+ 3.335X1+2.139X2-3.729X7+19.582X8 for 4 month old grouper， Y9=-313.801+17.985X1-7.144X3+11.193X4+37.145X8 for 9 month old grouper, Y15=- 897.768+20.951X1+70.512X4-33.298X7+81.547X8 for 15 month old grouper. There were positive correlations among phenotypic traits of the grouper with different month ages, with very significant positive correlation between body weight and various phenotypic traits of grouper with different month ages(P<0.01) except the correlation with X7 at the age of 9-months. The first principal component analysis reflected with ages of 4-months and 9-months and the body length gain, body weight gain and body depth factors in Yunlong grouper with age of 15-months. The second principal component reflected the caudal peduncle length factor in Yunlong grouper with 3 month old age. The maximal direct effect on body weight was total length in Yunlong grouper with age of 4-months (determinant coefficient of 0.485) and 9-months (determinant coefficient of 0.831), meanwhile, the maximal direct effect on body weight was body depth in Yunlong grouper with age of 15-months (determinant coefficient of 0.440), determinant coefficient analysis being consistent with that of path analysis. The findings indicate that the length growth and weight gain are main characteristics trend at three month stages, and that the established multiple linear regression equations can be used to estimate body weight of Yunlong grouper with different month ages.
2019, Vol. 34 
