摘要
为探究盐度在中华绒螯蟹(Eriocheir sinensis)交配和产卵前后对血淋巴中5种激素的影响,本研究分别设置了0、2、4、6的交配盐度和3、6、9、12、15、18、21的产卵盐度,分析了不同交配和产卵盐度条件下,中华绒螯蟹血淋巴中双羟基孕酮(DHP)、促性腺激素(GTH)、前列腺素(PG)、雌二醇(E_(2))和睾酮的含量变化。结果显示,在淡水中,雌蟹无交配行为发生,当盐度<6时,雌蟹只交配不产卵。雌蟹在盐度为2~6中交配后,血淋巴中GTH、PG、E_(2)和睾酮与交配前相比均无明显变化,且交配后各盐度组相比无显著差异(P>0.05)。随着盐度的升高,雌蟹产卵前,血淋巴中DHP、PG、E_(2)和睾酮的含量均呈先下降再上升的趋势;产卵后血淋巴中DHP、PG、E_(2)则呈先上升后下降的趋势,其中,当盐度为18时,雌蟹产卵后,血淋巴中DHP、GTH、PG、E_(2)和睾酮含量均降到最低,且与产卵前相比均有显著差异(P<0.05)。当盐度为6时,雌蟹产卵前血淋巴中DHP、PG、E_(2)和睾酮含量最高,产卵后DHP和PG的含量下降,而GTH、E_(2)和睾酮含量均呈上升趋势,但产卵前与产卵后相比除DHP有显著差异外(P<0.05),其他各项指标相比均无显著差异(P>0.05);此后,随着盐度的逐渐升高,产卵前后血淋巴中睾酮的含量呈先下降后上升的趋势。研究表明,盐度对中华绒螯蟹雌蟹交配和产卵前后血淋巴中5种激素产生了一定影响,其中,5种激素在中华绒螯蟹低盐度交配中的变化不显著,DHP、GTH和PG这3种激素参与了中华绒螯蟹的产卵活动。本研究通过探讨盐度对中华绒螯蟹雌蟹交配及产卵前后血淋巴中激素的影响,旨在了解中华绒螯蟹繁殖的生理机制,为中华绒螯蟹的繁育生物学研究提供基础资料和参考。
Chinese mitten crab(Eriocheir sinensis)belongs to Decapoda,Grapsidae and Eriocheir.It is also known as river crab and hairy crab and is widely distributed in the coastal waters of China and has important economic benefits.Salinity is the key environmental factor affecting the mating and spawning of E.sinensis.Presently,reports on the effects of salinity on crabs focus on osmotic pressure regulation,nutritional and energy metabolism,molting,and sexual precocity.However,the effects of salinity on the related hormones in the hemolymph before and after mating and spawning of E.sinensis have not been reported.Relevant steroid hormones include progesterone,17α-dihydroxyprogesterone,20β-dihydroxyprogesterone,and 17α-20β-dihydroxyprogesterone(DHP)and most effectively induce maturation of salmon and trout eggs,which has been confirmed in a variety of fish.Early studies have shown that the ovulation activity of fish is closely related to the level of gonadotropin(GTH)in the blood.The gonadotropin releasing hormone receptor(GnRHR)in E.sinensis indicate that the ovarian maturation and reproductive regulation in crustaceans are regulated by some gonadotropins,such as methylfarnesol and ecdysone.PGE,PGF,and prostacyclin(PGI2)can promote ovulation in a variety of fish and crustaceans.Like vertebrates,steroids are important hormones that affect the ovarian development of shrimp and crab,such as estradiol(E2),testosterone(T),and progesterone.Steroids can impact gonadal development and play a very important role in ovarian development and vitellogenesis.However,these hormones are restricted by a variety of environmental factors,such as temperature,light,salinity,and so on.In order to investigate the effect of salinity on hemolymph related hormones during mating and spawning of E.sinensis,the spawning salinity was set at 0,2,4,6 and mating salinity set at 3,6,9,12,15,18,21.Five samples were collected from specimens in each salinity to analyze the contents of DHP,GTH,PG,E2,and testosterone in the hemolymph of female E.sinensis before and after mating and spawning under different mating and spawning salinities.The components were detected by ELISA at the wavelength of 450 nm using the kit double antibody sandwich method.Results revealed:(1)in fresh water,female crabs displayed no mating behavior.When the salinity was lower than 6,female crabs only mated without spawning.(2)There were no significant changes in PG,E2,or testosterone in the hemolymph of female crabs after mating in low salinity(2-6),and there was no significant difference between crabs at different salinities after mating(P>0.05).(3)The contents of DHP,PG,E2,and testosterone in the hemolymph of female crabs initially decreased and then increased with salinity before spawning.After spawning,DHP,PG,and E2 in hemolymph initially increased and then decreased with increased salinity.When the salinity was 18,DHP,PG,E2,and testosterone in the hemolymph of the female crab after spawning decreased to the lowest level,and there was a significant difference between the before and after spawning results(P<0.05).(4)At 6 salinity,the contents of DHP,PG,E2,and testosterone in the hemolymph of female crabs before spawning were the highest and the contents of DHP and PG decreased after spawning,while the contents of E2 and testosterone increased.However,there was only significant variation in the DHP from before spawning to after spawning(P<0.05),and there was no significant difference in the other indexes(P>0.05).The content of testosterone in the hemolymph initially decreased and then increased before and after spawning.This comprehensive study showed that salinity effects the five hormones in the hemolymph of female E.sinensis during the reproductive and breeding stage.Among them,the five hormones do not change significantly during the mating process of E.sinensis.DHP,GTH,and PG are involved in the oviposition of E.sinensis.The analyses of the changes in the related hormones in the hemolymph of female E.sinensis before and after mating and spawning at different salinities have identified changes in the neutral hormones.These results provide details on the reproductive regulation mechanism of E.sinensis and provided basic reference data for researching the reproductive biology of E.sinensis.
作者
贺露露
耿智
黄晓荣
冯广朋
庄平
赵峰
张涛
杨刚
HE Lulu;GENG Zhi;HUANG Xiaorong;FENG Guangpeng;ZHUANG Ping;ZHAO Feng;ZHANG Tao;YANG Gang(East China Sea Fisheries Research Institute,Chinese Academy of Fishery Sciences,Key Laboratory of East China Sea and Oceanic Fishery Resources Exploitation and Utilization,Ministry of Agriculture and Rural Affairs,Shanghai 200090,China;College of Fisheries and Life Science,Shanghai Ocean University,Shanghai 201306,China;Shanghai Engineering Research Center of Fisheries Stock Enhancement and Habitat Restoration of the Yangtze Estuary,Shanghai 200090,China)
出处
《渔业科学进展》
CSCD
北大核心
2023年第5期162-171,共10页
Progress in Fishery Sciences
基金
国家重点研发计划(2018YFD0900903)
上海市中华绒螯蟹现代农业产业技术体系项目(沪农科产字2017-4号)
国家自然科学基金(31972795)
中央级公益性科研院所基本科研业务费专项(2020TD13)
国家科技资源共享服务平台共同资助。
关键词
盐度
中华绒螯蟹
交配
产卵
激素
Salinity
Eriocheir sinensis
Mating
Spawning
Hormone
