Motility And Cryopreservation On Sperm Of F₁-generation Of Chinese Sturgeon （Acipenser Sinensis Gray）

Acipenser sinensis Gray, mainly living in the continental shelf of the East China Sea and the Yellow Sea, is the only species of Yangtze Sturgeon that spawn in autumn and have the typical habit of Anadromous migration. Overfishing, water pollution and water conservancy and hydropower project construction together led to severely ruin to its habitat, shrinking number of its community and less distribution area.In 1996, it was included in Red List by the International Conservation Union (IUCN), also divided into endangered category.Acipenser dabryanu. which mainly distribute in the upper Yangtze river valley and the lower reaches of Jinsha River, is relatively small sturgeon that settled in freshwater without long distance spawning migration. It’s the National level to protect fish and typical endangered specie in Yangtze River.This dissertation studied the physiological characters of sperm of F1-generation of Chinese sturgeon and Acipenser dabryanus that under artificial cultivation, explored the connection between sperm mobility and concentration of irons and glucose, also compared to the wild parent Chinese sturgeon.aiming to provide scientific data to large-scale artificial reproduction in freshwater. Additionally, effects of sperm of F1-generation of Chinese sturgeon under deep freezing were studied, we mainly focused on how deep freezing affect energy metabolic enzymes and antioxidant enzymes after freezing by controlling the freezing time, in order to figure out the reason for cryodamage and offer theoretical and experimental basis for application and research of sperm freezing.1、 Sperm motility of F1-generation of Chinese sturgeon(Acipenser sinensis Gray) and Acipenser dabryanus was observed in various concentration of Na+, K+, Ca2+, Mg2+ and glucose.The results showed that the the longest LT (Life time) and FT (fast movement time) was 263.33 s and 45.33 s. When the concentration of K+ was 0.01‰, longest LT was observed with 132.33 s, while the longest FT was 46.00 s when K+ was 0.008‰. Similar changes of LT and FT were realized when sperm in Ca2+. When Ca2+ was 4‰, both LT and FT (130.67 s and 53.67 s) were the longest. The longest LT was 117.33 s when Mg2+ was 3‰, while the longest FT was 27.20 s when Mg2+ was 2‰. When the concentration of glucose was 4‰, the longest LT was 282.80 s, while the longest FT was 55.88 s when glucose was 3‰.Sperm of F1-generation of Acipenser dabryanus reached longest LT with 219.67s when the concentration of Na+ was 2.5‰, longest FT with 66.67s was realized when it was 2‰. While the concentration of K+ was 0.004‰, longest FT and LT was observed with 124.67s、52.67s respectively,whereafter, increasing concentration effectively restrain sperm mobility.In contrast to Na+、K+, along with the increasing concentration of Mg2+、Ca2+, to3‰、1‰ respectively, sperm tend to clump together; Accompany with increasing concentration of glucose, FT and LT were lengthened.Results indicated that Na+、K+ could effectively increased LT and FT of sperm F1-generation of Chinese sturgeon and Acipenser dabryanus, low concentration of Mg2+、Ca+ show strong restrain to sperm mobility, exogenous glucose can be used by sperm of Fl-generation and appropriate concentration can lengthen LT. Compared with wild parents of Chinese sturgeon, LT and FT of F1-generation were both lower.2、Sperm was under deep freezing for 30d,45d,60d respectively, energy metabolic enzymes and antioxidant enzymes were detected with kit (Nanjing, Jiancheng) after thawing, including total ATPase, SDH, LDH, CK, ACP, SOD, CAT, GSH-PX and GR. Results showed that there is significant difference (P< 0.05)between enzyme activity in seminal plasma and sperm after freezing.Expect GR, others’activities in sperm obviously decrease, while enzymes activities in seminal plasma significantly increase.In addition, metabolic enzymes and antioxidant enzymes activities change with the time that sperm have been frozen. After being frozen for 30d, enzymes activities except GR are higher than that of sperm being frozen for 45d and 60d (P< 0.05); enzymes activities in seminal plasma are opposite, indicating that longer freezing time strongly damage the sperm. GR activity in sperm increase along with the freezing time extend, ituation in seminal plasma is reverse. Enzymes activities are significantly affected in sperm and seminal plasma of F1-generation of Chinese sturgeon by deep freezing, the control of freezing time plays a vital role in deep freezing.