| As rare high-grade reef fish, Cheilinus undulatus is scarcity of wild natural resources, while the artificial breeding is difficult. This paper detailed studied the brood stock gonad histology, culture technique for brood stock and individual early development of C. undulatus. Reveals the reproductive biology characteristic in artificial breeding, provides theoretical foundation of artificial reproduction.Using paraffin section technique, electron microscope scanning technology has researched gonadal histology and sperm morphology of C.undulatus. Preliminary observation only know C.undulatus gonad development regularities and sperm morphological characteristics. The female fish generally are smaller than males of C.undulatus. There is different period oocyte in the ovary during the same period. Ovarian development is better from month5to month7, generally in III final or phase IV, ovaries in the third or fourth phase of oocytes. Histology showed, the parent fish of ovarian development is common from August to December. Ovaries to2,3phase oocytes. Ovary oocytes when each phase in the different period of the type and proportion of different, Ⅱ period in the ovary, when the second phase oocytes accounted for more than90.0%of the total. When III period in ovary,3phase oocytes by more than77.8%of the total number of plane cells. IV period in ovarian,4phases during oocyte accounted for more than60%of the total plane cells. Individuals generally larger than females, male C.undulatus spermary lobular type structure, develop together in5～7months to Ⅳ～Ⅴ period. Electron microscope scanning results show that the C.undulatus sperm morphology and bony fishes generally similar, the head without body, long tail.Accordingly, C.undulatus is asynchronous spawning fish, the female and male gonad development consistent, which is of great significance to the development of artificial breeding. Forward foster parent fish method is used to analyze the C.undulatus breeding, only makes the gonads mature and lay eggs. Set to choose appropriate waters using fresh fish, squid and crab crustaceans as bait, enough times feeding method of only11female,5specimens intensive cultivation.Parent fish always weighs about803.5kg, feed the bait every day is about10.0kg, food intake is about0.6kg, feeding rate of about1.2%. Only after51days of cultivation, the gonads mature, fostering good C.undulatus parent fish under the condition of artificial fish can batch to lay eggs. Received total eggs during spawning quantity is10.97kg, in which the fertilized egg4.96kg, fertilization rate was45.2%. Breeding period, the group is only a tail (individual) largest male fish in breeding, paired with1～2female fish every day, until all the females lay eggs.Optical microscope was used to observe C.undulatus of the whole process and the larvae. The results show that the C.undulatus eggs are round, colorless, transparent, buoyancy eggs, egg with a light oil. Its egg diameter (635.6±50) microns, significantly less than other sea fish. The fertilized egg in30,27.7～29.0℃temperature of the seawater salinity,15hours and30minutes hatched larvae. The new-hatching larvae is colorless of the whole body, full length (1305±50) microns, has a large ellipsoid yolk sac, oil ball is located in the forefront of yolk sac. It has no activity, suspended in the water. Fertilized egg in the process of development, the neural plate in the middle and later periods of the archenteron has appeared. In the conditions of similar temperature, the embryonic development speed obviously faster than other sea fish. |
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