| Sebastes schlegeli is mainly distributed in the Pacific Northwest,it’s one of mostimportant economic fish which located in the Bohai Sea, the Yellow Sea and the EastChina Sea area in China. In recent years, due to enviromental pollution and overfishing,the number of wild Sebastes schlegeli declined rapidly..However, its meat is deliciousand nutricious, so there is a broad market prospects in the culture of Sebastes schlegeli.In this study, with methods of morphological and histological,blood cell andbiochemical analyzer instrument, Sebastes schlegeli was studied in cage, hoping itsbreeding and sea-scale production to provide some scientific basis. The following arethe details:1. Ovarian development of Sebastes schlegeliWith methods of morphological observation and conventional histological biopsy,the ovarian development of Sebastes schlegeli was researched from February to June,and systematically described the shape and structure of ovary maturation andreproduction(Ⅲ, Ⅳ, Ⅴ,Ⅵstage and degradation Ⅱs tage) and characteristics andchanges of oocytes. The results showed that ovarian development was in stage Ⅲ fromlate February to late March.In this period, ovary was given priority to with Ⅲ phaseoocytes. And ovary began to appear yolk granules, cortical vacuole and reflective filmstructure.When came to the stage Ⅳ, from late March to early April, ovary was givenpriority to with Ⅳ phase oocytes，and yolk granules were full of ovary at this stage;and then, when the ovarian developed into Ⅴ period,from mid-April to early May, wecan clearly see theⅤ oocytes in the ovary,the cell was flooded with mature yolkgranules.In early May, the ovary continued development to Ⅵ period, calledpregnancy ovary,filled with fertilized egg. When the females finished giving birth tolarvae,from mid-May to early June,the ovary developed to enter degragation Ⅱperiod,less the residual phase egg part. 2. Morphometrics development of Sebastes schlegeli larvae and juvenileWith methods of anatomical observation, revealing the post-embryonicorganization development of Sebastes schlegeli in detail, the result shows that:0dphfry, the total length(TL) is3.8～4.7mm,the oil ball is big and clear;1dph fry(Initialhatch fry),TL is5.0~6.5mm, the fry’s mouth has been open, and not feeding, melaninonly distributes on the surface;2dph,the fry start feeding rotifer, the maw has gas,andrainbow color element emerges;3dph fry, a bundle pigment appears on the rear braincase, and the tail radiation silk appears, the food consumption increases greatly;4dph,fry, yolk sac has been absorbed, spotted yellow pigment begins to differentiate at theback of head and the top of abdominal cavity;5dph, pectoral fin vertically spreadsoutward, jaw opens frequently.12dph, the fry is clustered and phototropic;20dph, thefront part of the fish is black, the fish disperses evenly in water, feeding exuberant;25dph, TL is6.55～8.42mm, black stripe mark begins to appear in front part of the fish;30dph, on the edge of the head eye, there is a horizontal belt, three dark brownhorizontal stripes appear at the fish body side;40dph, TL is15.50～35.55mm, the bodyshape is similar to the salted fish, there are6~7dark brown horizontal stripes at thebody side;60dph, the body shape is consistent with the adult, body development goesinto the juvenile stage, and begins to live in the lower water. Based on themorphological observation of ovoviviparous Sebastes schlegeli in early development,and the embryo, larvae and juvenile developmental regularity and species specificity,not only can we enrich our understanding of the early life history of the fish, but alsoinstruct the production and breeding of Sebastes schlegeli in the future.3. The early gonadal development and gonadal differentiation of Sebastes schlegeliEarly gonadal development and differentiation of Sebastes schlegeli was researched bythe method of microscopic observation of tissue section, the result showed as follows:the10-dpb larvae, a total length of7.82-8.20mm,primordial gonadals appeared in theform of a reproductive group; the30-dpb larvae, full length18-21.2mm, a primordialgonads has been completely formed, to this stage, showed obvious features of theovary and testis differentiation was not found in the gonads; the40dpb larvae, totallength is33.2-38.7mm, two different shapes of the gonads, one of them still remained primitive gonad characteristics, another part of the gonads with the primordial gonadsmarked the Sebastes schlegeli gonadals differentiation beginning;100dpb larvae, thetotal length of58.5-62.4mm,the ovarian cavity fully formed far found no obviousfeatures characteristic of testis differentiation.4.Serum biochemical indicators of Sebastes schlegeli under different oxygenconcentration treatment:The blood cells and the biochemical indicators of Sebastes schlegeli comparedunder different oxygen concentration treatment by blood cells and biochemicalsanalyzer. The results showed as follows: Sebastes schlegeli serum enzyme alanineaminotransferase, aspartate aminotransferase over time within each group weresignificantly increased(P<0.05), and in60min when the hypoxic group of alanineaminotransferase,aspartate aminotransferase significantly(P<0.05) higher than in thehypoxia group and hyperoxia group. Alkaline phosphatase in each group is decreasedas the oxygen content decreased, but not significantly (P>0.05),;the blood cellschanged as follows: in hypoxia group, white blood cell was significantly reduced(P<0.05),red blood cell counts and hemoglobin increased significantly(P<0.05) withlower oxygen content in water; in Sebastes schlegeli serum ions, differentionconcentration increased with the oxygen content of the water body have differentdegrees of rise（Ca（P>0.05）、P（P>0.05）、cl(P<0.05)、Na(P<0.05)）; hypoxia organicingredients of Sebastes schlegeli serum found that uric acid and creatinine levels weresignificantly increased（P<0.05）within each group. For urea, total cholesterol, glycerolester analysis, the differences between groups were not significantly(P<0.05).Byanalysis of Sebastes schlegeli serum biochemical indicators, hypoxic conditions causedlimit of liver, heart and gill damaged and blood-forming organs. |
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