Comparison of development and growth of hybrid Chromileptes altivelis (♀) × Epinephelus tukula (♂)

We performed breeding experiments with Chromileptes altivelis as the female parent and Epinephelus tukula as the male parent by artificial fertilization to breed new species of groupers with excellent traits. Besides, we observed and compared the embryonic development and growth characteristics of C. altivelis (♀) ×E. tukula (♂) and C. altivelis by microscope (Nikon E200) and anatomic microscope (Olympus). The results show that the fertilized eggs of the hybrid and C. altivelis took 24 h 50 min and 25 h 8 min to accomplish the embryo development under the conditions of water temperature 27 ℃, salinity 30, pH 8.1 with the micro-flowing water and micro-inflated water, respectively. The post-embryonic development of the hybrid had experienced four stages of early larva (0−3 d), late larva (4−40 d), juvenile (41−60 d) and young fish stages (after 61 d). At 330 days of age, the total lengths of the hybrid and C. altivelis were (23.57±0.94) cm and (18.35±0.72) cm, respectively; and the body masses were (220.5±25.3) g and (142.6±0.58) g, respectively. The total length and body mass of the hybrid were 1.28 and 1.55 times that of the C. altivelis, respectively. Compared with C. altivelis in the external morphological traits, the hybrid was slender and the head was larger, the black spots on the body surface was distributed disorderly, and the fins of each part was relatively small. Based on our tracking observation on embryo and larval development of hybrid, it is confirmed that the distant hybridization combination of C. altivelis (♀) ×E. tukula (♂) is feasible, and the hybrid shows the merit of heterosis, which provides scientific basis for distant hybridization and the cultivation of new varieties of groupers.