A Preliminary Study Of Trachidermus Fasciatus Gonad And Prelarva Development Crucial Impaction And Physiological Characteristics

Trachidermus fasciatus as one of China’s four big name of freshwater fish, is anational secondary protection of wild animals, famous both at home and abroad, dueto its sweet-meated has high economic value. In the history, China’s coastal areas andconnected to the fresh water have the distribution of it. Currently the species havevanished in most waters, resources are endangered. So to Trachidermus fasciatus ofdevelopmental biology research has the vital significance, can provide scientificguidance for better protection of the species. This paper uses the histologic, RIAmethod, and body composition measurement method for study of the developmentand reproduction, located in Qingdao dagu river basin and coastal development ofsongjiang perch and breeding index were determined, specific research contents andresults are as follows:1、Collected dagu river basin in November to January of next year of songjiangperch in three individuals, anatomical sex gland tissue section analysis. The resultsshow that in November, the majority of ovarian are in Ⅲ stage, the same phase ofoocytes started to enter the big growth period; In December, for Ⅳ period ovary,most of the oocyte in Ⅳ phase, there are also a small number of oocytes are stillundergoing Ⅲ phase of development state; The following year in January in Ⅴperiod. In November, samples were collected,most of testis has entered Ⅳ period;Samples were collected in December, testis have further development, for Ⅳ lateperiod; The following year in January, according to the biology department of fudanuniversity of zoology and the anniversary of the change in the classification aboutsongjiang perch gonad, this period still belongs to Ⅳ late stage. For wendeng,located in the coastal fishing larvae larval tissue slice observation, because sampling condition, not the development period of continuous sampling investigation,observation is limited to the number of tissues and organs in the eye and the digestivetract.2、By using the method of radiation immunoassay (RIA) in three months ofsongjiang perch fish gonads neutral steroids, the change of FSH and LH wasdetermined. The results showed that:（1）Songjiang perch female gonad of estradiollevels in the early stage of the breeding of a few months to maintain a relatively stablelevel, is a weak downward trend, in November and the following year in January,there are significant differences (P <0.05); The change of the gonads of testosteroneis on the decline, in November and December and January the following yearsignificant difference (P <0.05).（2）Male songjiang perch individual content ofestradiol in the gonads presents downtrend in three month, The following year inJanuary and November and December significant difference (P <0.05); Testosteronelevels also showed a trend of decline in three months, in November and Decemberand January the following year significant difference (P <0.05).（3）Femalesongjiang perch in the individual, the gonads of FSH of the obvious upward trend inthe three months, three months there were significant differences (P <0.05), contentdetection not to come out in November; LH level in three months is on the decline,but no significant difference were observed in the three months (P>0.05).（4）Malesongjiang perch in the individual, the gonads of FSH levels had fallen for threemonths, but no significant difference were observed in the three months (P>0.05);LH levels in three months after rising to decline, and in November and Decembernext year in January, there are significant differences (P <0.05).3、For the first three months of songjiang perch body tissue elements weredetermined, the results show:three months, songjiang perch body tissue componentsof the water content in general is on the rise, content is around72%, in November andDecember and January the following year significant difference (P <0.05); threemonths ash content is on the rise, the average around6%, no significant differencewere observed in the three months (P>0.05); crude fat in the three months to presentdownward trend after rising first, three in all significant difference (P <0.05); three months of the fish is on the decline, the content of crude protein in November andDecember and January the following year significant difference (P <0.05).