| Studies were carried out on the gonadal of Varicorhinus macrolepis ,with regards to its morphological, histology and the electronic morphology of the mature sperm during the testicular reproductive cycle and spermatogenesis of , as well as the changes of sex hormone during annual reproductive cycle . Test 1: Study on the development of testis in annual reproductive and spermatogenesis of Varicorhinus macrolepis .The male Varicorhinus macrolepis has two testes ,which are located above the dorsal gut . The part of the testis attached the two sides of the ventral swin bladder , in which side there have a groove in the testis , blood vessles . Vasa deferentia joint together in the end of testis lined with vasa efferentia and open to urinogenital hole .The testis of Varicorhinus macrolepis are lobular-type structure , in which the cysts are the basic unit . The germ cells in one cyst has the same phase ,but in different cyst the germ cell perhaps are at the same phase . when the germ cells in the cyst develop to sperm , it was secreted to seminiferous lobular cavity , the sperm are transferred to outerside through vasa deferentia during reproductive season . The anatomy , histology of Varicorhinus macrolepis show seasonal changes in annual cysles . On the base of Cybopob.e.k(1948) ,Liuyun(1993)and MeИeH , the development steges of Varicorhinus macrolepis were determined according to its anatomy ,histology and the development characteristics of germ cells , the testis of matural Varicorhinus macrolepis were classified into five stages during the annual reproductive cycle ,which were as follows : (1) Stage Ⅱ: in August of every year,the testes are at the stage of spermatocyte proliferation .(2)Stage Ⅲ: from September to January next year ,the testes are at the stage of spermatocyte maturation .(3)Stage Ⅳ: from February to April ,the testes are at the stage of sperm appearance . (4)Stage Ⅴ: from May to June ,the testes are at the stage of sperm maturation . During this spawning period, the amount of matured sperm increase sharply .(5)Stage Ⅵ :in July ,the testis are at the stage of sperm degeneration and absorption .During this stage , most remains of sperm are absorpted.Through the study on the GSI of male matural Varicorhinus macrolepis ,we could found that the GSI went up to peak in May . Examined with light microscope, large amount of matural sperm could be found in the testes this time , from these we can find that the testes of Varicorhinus macrolepis most active only between May to june every year .Spermatogenesis passed through primary spermatogonia stage , secondary spermtogonia stage , primary spermatocyte stage, secondary spermmatocyte stage , spermatid stage , spermatoblast developed to sperm in the end . The primary spermatogonia are the spermatogenic stem cell in the testis of male matural Varicorhinus macrolepis . Spermatogonia is the biggest germ cell in testis . Its nucleoli is apparent and the chromatin is low-elecon-densed . There are abundant mitochondria such as Golgi complex ,chromatoid ,etc. The spermatozoon should pass through nucleus condensed ,flagellum formed , sleeve formed .etc . The spermatozoon of the teleost , Varicorhinus macrolepis consists of three parts : head ,mid-piece ,sperm tail . sperm head contains nucleus , The head is like a globe or an ellipsoid. There is no acrosome at the anterior end of the nuclears. The mid-piece contains centriolar complex and sleeve .The tail of sperm is flagellum, the main structure of the tail is axoneme ,which is the structure of a typical"9 + 2". There are no vesicles nor other cell organelles in the tail .Test 2 Study on the changes of sex hormone in Varicorhinus mcrolepis in annual year and the reproductive cycle .Blood samples were collected by injectors from Varicorhinus macrolepis every month , Plasma testosterone was detected with radio immunoassay (RIA) . The results show that the level of Plasma testosterone displayed seasonal variation . The main value of T went up to peak in April before sperm...
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