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裸腹鲟(Acipenser nudiventris)曾广泛分布于欧洲的黑海、亚速海和中亚的里海、咸海, 以及上述区域的一些河流中, 在中国仅自然分布于新疆伊犁河流域, 被世界自然保护联盟《濒危物种红色名录》列为极危物种, 是《濒危野生动植物种国际贸易公约》附录二保护物种, 也是我国的国家二级保护野生动物, 新疆维吾尔自治区一级保护野生动物。受多种因素影响, 伊犁河流域野生裸腹鲟已濒于绝迹。本研究对人工驯养条件下的伊犁河裸腹鲟成年个体开展了人工繁殖、胚胎发育和苗种培育等方面的研究。在共计 13 尾野生裸腹鲟中, 有 2 尾雌鱼和 3 尾雄鱼性腺发育达到了 IV 期, 采用 LHRH-A2 对性腺发育至 IV 期的 2 尾雌鱼和 3 尾雄鱼实施了人工催产和授精, 获卵 12 万粒, 受精率为 55%。在 15~17 ℃的孵化条件下, 裸腹鲟仔鱼经 5~7 d 孵出, 获得裸腹鲟鱼苗约 25200 尾, 孵化率 42.5%。 相似文献
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取7龄西伯利亚鲟(AcipenserbaeriBrandt),第1次产卵前4个月,放入2组不同温度的水池中越冬,Ⅰ组水温13～14℃;Ⅱ组7～8℃。每组4尾雌鱼,6尾雄鱼。催产前水温升至15～16℃,人工催产结果,Ⅰ组1尾雌鱼排卵和2尾雄鱼排精,Ⅱ组3尾雌鱼排卵,5尾雄鱼排精;雌鱼排卵全部采用输卵管切割手术取卵,获得成熟卵3.26kg,共计21.5×104粒;用“半干法”授精,获受精卵19.11×104粒,受精率86.7%～95.6%;孵出鱼苗12.5×104尾,孵化率40%～68.9%。结果说明,在人工培育条件下,西伯利亚鲟能够成熟并成功地进行人工繁殖;产前培育温度变化对西伯利亚鲟性腺发育和人工繁殖效果有明显影响;与养殖施氏鲟的人工繁殖比较,催产效应时间基本相同;雄鱼发育较差。 相似文献
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西伯利亚鲟性别及性腺发育的超声波鉴定 总被引：1，自引：0，他引：1
利用超声波检查仪对人工养殖西伯利亚鲟的性别及性腺发育进行超声波扫描,并利用微创手术检查和组织学观察法来验证超声波对西伯利亚鲟性别及发育时期扫描的鉴定结果。通过对比研究表明:超声波方法对西伯利亚鲟性别鉴定的准确率较高,对2～5龄雌性鉴定的准确率为95%,对雄性鉴定的准确率为87%。超声波技术鉴定性腺发育的准确率随性腺的发育而提高,鉴定早期性腺(Ⅰ～Ⅱ期)发育的准确率(65.25%)低于对晚期性腺(Ⅲ～Ⅴ期)发育鉴定的准确率(88.65%)。超声波技术鉴定西伯利亚鲟性别及性腺发育速度较快,根据鱼的发育状况,平均每尾鱼所用的时间约30s。 相似文献
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自20世纪80年代开始,中国水产科学研究院长江水产研究所就开始进行中华鲟全人工繁殖研究。近15年来,长江所利用养殖的280多尾成年中华鲟进行全人工繁殖研究,先后成功攻克了后备亲鱼人工驯养、性腺发育诱导、人工催产等技术难关,并于近期取得突破性进展。 相似文献
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濒危中华鲟人工群体的繁殖生物学 总被引：2，自引：2，他引：0
以1998―2008年孵出的子一代(F1)中华鲟(Acipensersinensis)为材料,研究了人工养殖中华鲟的繁殖生物学特征。结果表明:年龄10～20龄的492尾人工养殖子一代中华鲟体重为30～169 kg,体长为140～258 cm,肥满度为0.77～1.26,体长(L)与体重(W)之间的关系式为W=1×10~(–5)L~(2.9658) (R~2=0.9076,n=492)。74尾中华鲟性腺发育成熟,成熟比例为15.04%,成熟个体中雄鱼体重[(60.73±14.53)kg]和体长[(172.27±13.46)cm]均小于雌鱼体重[(88.39±29.14)kg]和体长[(193.37±18.90) cm];雄鱼最小性成熟年龄为10龄,平均为(14.96±1.93)龄,雌鱼最小成熟年龄为12龄,平均为(17.84±1.80)龄。雄鱼催产成功率为76.36%,精子快速运动时间为(49.11±13.38) s,精子寿命为(220.75±56.47)s;雌鱼催产成功率为57.89%,产卵量为(13.43±6.79)万粒,卵径(3.97±0.15)mm,卵重(0.046±0.013)g,受精率为(42.72±27.82)%,孵化率为(51.61±32.41)%,出苗量为(4.44±5.67)万尾。与野生中华鲟相比,人工养殖中华鲟成熟个体体格、繁殖力和繁殖效果均有下降趋势,人工保种面临挑战。 相似文献
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《海洋渔业》2021,43(3)
通过对1尾养殖过程中死亡的子一代中华鲟(Acipenser sinensis,14+龄,体长163 cm,体质量51.54 kg)的死亡原因调查、分析,发现该尾中华鲟为雌雄同体。经对其性腺组织的影像及组织切片观察,发现该中华鲟性腺同时存在精巢和卵巢,性腺以精巢为主,精巢上间生多叶卵巢组织,左侧性腺长61 cm、重0.436 kg,右侧性腺长64 cm、重0.422 kg,性腺上附着有占比较大的脂肪组织,精巢和卵巢均处于Ⅱ期发育时相。该尾雌雄同体中华鲟的发现,是人工养殖条件下中华鲟成鱼雌雄同体现象的一个例证,其发生的原因、机制及其价值尚有待进一步研究和探讨。 相似文献
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乌苏里江唇(鱼骨)的全人工繁育 总被引：3，自引：1，他引：2
从乌苏里江捕获野生唇(鱼骨)(Hemibarbus labo)亲鱼150余尾,经人工繁殖获得鱼苗,饲养于池塘中,研究其在人工养殖条件下的生长、繁殖和性腺发育等生物学特性.结果表明,野生亲鱼及其F1在池塘中饲养下,性腺可自然发育至成熟,繁殖季节(5-6月)雌、雄亲鱼会出现明显的副性征,注射催产激素HCG、LRH-A2和DOM的混合制剂,可促使成熟的雌性亲鱼产卵,水温22～26℃时,药物的效应时间在17～22 h,人工繁殖的催产率、受精率、孵化率和畸形率分别为87.55%、68.95%、92.5%和5.75%.唇(鱼骨)的卵为圆形、灰白色或淡绿色,遇水后产生较强的黏性,吸水膨胀卵径为(2.32±0.12)mm(n=50),体质量400～900 g的雌性亲鱼绝对怀卵量为(3.19±0.85)×104粒(n=15).水温22～24℃时,从卵授精到仔鱼孵出需要积温69.43℃·d,到仔鱼平游摄食需要积温139.25℃·d,刚出膜的仔鱼全长(6.1±0.3)mm,平游时全长达到(8.9±0.4)mm.在哈尔滨地区人工池塘养殖唇(鱼骨),1+龄鱼体质量为(17.20±2.46)g,2+龄鱼为(89.84±9.30)g,3+龄鱼为(234.94±25.94)g,4+龄鱼为(371.57±64.65)g;雄性3+、雌性4+有部分个体性腺成熟,5+龄时多数个体可发育至性成熟.唇(鱼骨)的全人工繁育成功,可初步解决苗种来源和池塘养殖问题,并为野生资源的增殖和人工规模化养殖奠定基础. 相似文献
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《中国水产》2012,(12):41-41
11月4日,由中国水产科学研究院长江水产研究所承担的公益性行业（农业）科研专项“珍稀水生动物繁育与物种保护技术研究”课题1——“中华鲟规模化全人工繁殖及迁地保护技术研究”阶段性成果通过了农业部渔业局组织的验收。这标志着历经30年研究,中华鲟全人工繁殖获得了成功,中华鲟连续多代繁育将变为现实。自20世纪80年代开始,长江所就开始进行中华鲟全人工繁殖研究,并开展人工增殖放流活动。近15年来,长江所利用养殖的280多尾成年中华鲟进行全人工繁殖研究,先后成功攻克了后备亲鱼人工驯养、性腺发育诱导、人工催产等技术难关,并于近期取得突破性进展。10月28至30日,长江所对人工培育成熟的子一代中华鲟进行人工催产和授精, 相似文献
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中华鲟血清卵黄蛋白原水平的初步观察 总被引：1，自引：0，他引：1
通过碱不稳定性蛋白结合磷法测定不同年龄中华鲟(Acipenser sinensis)血清中磷含量,以磷的含量变化反映卵黄蛋白原(VTG)变化情况。实验鱼为人工养殖0.5、1、2、3、4、5、6、8、9、10龄中华鲟和野生成熟中华鲟,共81尾,其中8尾野生雌鱼在人工繁殖前后各取样2~4次,共测97个血液样本。结果显示:低龄中华鲟VTG含量较低,最低值在5龄,含磷量为(4.6±1.6)mg/L,5龄后增加,成熟后达到最大,含磷量为(52.0±4.5)mg/L。在性腺不同发育时期,雌性个体在Ⅱ~Ⅴ期VTG的含量增加,Ⅱ~Ⅲ期增加速度较快,随后变缓,Ⅴ期达到最高水平,Ⅵ期降低;而雄性个体在Ⅱ~Ⅳ期VTG的增加量很少,Ⅳ期达到最高水平,含磷量为(28.7±12.2)mg/L。繁殖雌鱼产前VTG含量最高,含磷量为(62.5±8.7)mg/L,产后低于产前。此外,发现产后鲟鱼卵巢液中含量低于其血清中含量,但高于其他年龄组血清中的水平。本实验表明淡水养殖的中华鲟有可能达到性成熟。 相似文献
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Association between the interannual variation in the oceanic environment and catch rates of bigeye tuna (Thunnus obesus) in the Atlantic Ocean 
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下载免费PDF全文 The environmental processes associated with variability in the catch rates of bigeye tuna in the Atlantic Ocean are largely unexplored. This study used generalized additive models (GAMs) fitted to Taiwanese longline fishery data from 1990 to 2009 and investigated the association between environmental variables and catch rates to identify the processes influencing bigeye tuna distribution in the Atlantic Ocean. The present findings reveal that the year (temporal factor), latitude and longitude (spatial factors), and major regular longline target species of albacore catches are significant for the standardization of bigeye tuna catch rates in the Atlantic Ocean. The standardized catch rates and distribution of bigeye tuna were found to be related to environmental and climatic variation. The model selection processes showed that the selected GAMs explained 70% of the cumulative deviance in the entire Atlantic Ocean. Regarding environmental factors, the depth of the 20 degree isotherm (D20) substantially contributed to the explained deviance; other important factors were sea surface temperature (SST) and sea surface height deviation (SSHD). The potential fishing grounds were observed with SSTs of 22–28°C, a D20 shallower than 150 m and negative SSHDs in the Atlantic Ocean. The higher predicted catch rates were increased in the positive northern tropical Atlantic and negative North Atlantic Oscillation events with a higher SST and shallow D20, suggesting that climatic oscillations affect the population abundance and distribution of bigeye tuna. 相似文献
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Liping Li Rui Wang Wanwen Liang Xi Gan Ting Huang Yan Huang Jian Li Yunliang Shi Honglin Luo Ming Chen 《广西水产科技》2014,(1)
Previously, we reported 10 PEGE types of 85 tilapia Streptococcus agalactiae(GBS), which shifted from Streptococcus iniae in China, by using PEGE method. Presently, larger and more representative tilapia GBS were isolated, for the ?rst time in China, to characterize their serotypes and genetic diversities more precisely than had done before. 168 GBS strains were distributed in ?ve provinces of China, in which Guangdong, Guangxi and Hainan were the major ones, holding36.9%(62/168), 37.5%(63/168) and 19.6%(33/168), respectively. Serotypes, Ia, Ib and III, were observed in these strains and the most predominant one was Ia(95.2%), which mainly distributed in Guangdong, Guangxi and Hainan. Ia initially occurred in 2009, it shoot up to 32.1% in 2010,but decreased to 16.1% in 2011 before went up to 45.2% in 2012. Ib sporadically occurred during2007–2011, III onlyoccurred in 2012. 14 different PFGE types, including 4 new types(N, O,P and Q), were observed, in which B, D, F and G were the predominant types, holding 83.9%(141/168) of the total GBS strains. Ia corresponded to 11 PFGE types(A–H, N–P), in which type D predominated(51%). Ib represented 3 genotypes(I, J and Q) and III harbored only 2genotypes(N and F). Type N and Fsynchronously presented in Ia and III. In summary, the genetic diversity of tilapia GBS varied by serotypes and changed with geographical locations and years.Although Iastillpredominated, new rareserotypeIII alreadyoccurred in China. 相似文献
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In this experiment, a feeding trial was performed to determine the effects of fructooligosaccharide (FOS) on growth performance, digestive enzyme activity and immune response of Japanese sea bass, Lateolabrax japonicus juveniles (initial weight 38.3 ± 0.5 g), and the fish were examined following feeding with six levels of FOS (0, 0.5, 1, 2, 4 and 6 g/kg) for 28 days. Significant enhancement of weight gain (WG) and specific growth rate (SGR) was found in fish fed 1 g/kg FOS incorporated diets (p < .05), while the feed conversion ratio (FCR) in the 1, 2 g/kg FOS groups reduced significantly compared with the control (p < .05). Besides, the crude lipid in the 4, 6 g/kg FOS groups increased significantly compared with the control (p < .05). On the other hand, the erepsin and lipase activities significantly elevated in intestine of fish fed 2 g/kg FOS (p < .05) and the lysozyme activity in serum of fish fed 2 g/kg FOS were significantly higher than that in the control (p < .05). Moreover, the alkaline phosphatase activities in serum of fish fed 0.5, 1, 2 g/kg FOS were significantly higher than in control (p < .05). Regression analysis showed that the relationships between dietary FOS levels and either SGR, FCR, erepsin or lysozyme activities were best expressed by regression equations, and the optimal inclusion levels are 1.37, 1.80, 3.06, 3.11, 1.93 and 1.80 g/kg for SGR, FCR, erepsin, lipase, lysozyme and total superoxide dismutase activities, respectively. Overall, this study revealed that FOS incorporated diets could beneficial for L. japonicus culture in terms of increasing the growth, digestion and immune activities. Under the present experimental condition, the optimal supplementary level of FOS in the diet of L. japonicus is 1–3 g/kg. 相似文献
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Iciar Martinez Amaya Velasco Ricardo Pérez-Martín Eskil Forås Michiaki Yamashita Carmen G. Sotelo 《Journal Of Aquatic Food Product Technology》2013,22(4):289-297
The purpose of this work was to evaluate the suitability of a method based on the presence of two restriction sites (for Hae III and Hindf I) in the mitochondrial NADH dehydrogenase subunit 5 (mt ND5) gene to identify Scomber species. The evaluation was performed on 144 reference and market samples by sequencing of the entire 505-bp fragment of the mt ND5 gene and of a 464-bp fragment of the Kocher fragment of the cytochrome b gene (mt Cytb). Sequence analysis of any of the two fragments allows the identification of each of the four Scomber species, but S. japonicus and S. colias had the same restriction sites at the ND5 amplicon and would not have been differentiated by this analysis. Similarly, loss of the Hae III site in some S. scombrus individuals would have misidentified them as not being Scomber. All the market products were correctly labeled except one acquired in Spain labeled as originating in the Atlantic and containing S. japonicus. 相似文献
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Two gonadotropins (GtH; Qa and Qb) were purified by gel filtration and ion exchange chromatography from the pituitaries of Indian walking catfish (Clarias batrachus). The presence of GtH during purification was assessed by in vitro oocyte maturation and in vivo steroidogenic activity, and their identities were determined by elution profiles, molecular weight, biological activities and yield. The molecular weights of Qa and Qb were 37 and 42 kDa, respectively, and composed of distinct subunits (Qa: 20 and 14 kDa and Qb: 26 and 18 kDa). Polyclonal antibodies raised against Qa immunostained Qa, Qb and pituitary GtH cells. A competitive Qa‐ELISA was developed whose sensitivity was 6.25 ng mL?1 (1.25 ng well?1) with intra‐ (3.5%) and inter‐ (12.4%) assay coefficients of variation. Displacement curves parallel to the standard were obtained with plasma and pituitary extracts of catfish, Qb and carp GtHII. The assay was validated by measuring the plasma Qa levels after LHRH treatment and in relation to ovarian growth in the female catfish during different reproductive phases. Based on the results, Qa and Qb corresponded to fish LH and FSH respectively. The findings will increase the knowledge of the mechanisms controlling fish reproduction and identification of sensitive phases in fish in captivity for hormonal manipulation. 相似文献
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Controlled infection of Poecilia reticulata Peters (guppy) with Tetrahymena by immersion and intraperitoneal injection 下载免费PDF全文
下载免费PDF全文 G Sharon M Pimenta‐Leibowitz M C L Vilchis N Isakov D Zilberg 《Journal of fish diseases》2015,38(1):67-74
Tetrahymena is a protozoan parasite, which infects guppy, Poecilia reticulata Peters, and causes substantial economical losses in commercial farms worldwide. Studies of guppy infected by Tetrahymena require standardized infection protocols. The LD50 for Tetrahymena infection of guppies by intraperitoneal (IP) injection was calibrated, and the level obtained was 946 parasites per fish. Guppy infection with Tetrahymena by immersion, imitating the natural route of infection via the integument, was studied under normal or stress conditions. Exposure to cold and netting (CNI) and to cold only (CI) followed by immersion exposure to 10 000 Tetrahymena per mL resulted in 22.5% and 19.2% mortality, respectively, as compared to 14.2% and 10% in groups that were netted only (NI) or non‐stressed (I). Histopathology revealed that immersion infection resulted in a systemic infection. Lysozyme levels, measured 3 weeks after infection, were significantly higher in the CNI group (288 μg per mg protein) compared with CI‐, NI‐ and I‐treated groups (94.5, 64 and 62.3 μg mg?1, respectively). There was no evident parasite immobilization activity in body homogenates, suggesting no development of acquired immunity. Re‐infection by IP injection revealed no increase in protection in any of the treatment groups, mortality range of 56.3–75%, higher than in the non‐exposed control (40.6% mortality). 相似文献
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Qin-Cheng Huang Di‐Gen Qin Bei‐Ping Tan Tao Du Yuan-Zhi Yang Qi-hui Yang Shu‐Yan Chi Xiao-hui Dong 《Aquaculture Research》2020,51(2):816-827
A 5 × 3 factorial growth trial was conducted to evaluate optimal dietary protein and lipid levels (dietary protein level, DP; dietary lipid level, DL) for juvenile Sillago sihama (S. sihama) (2.0 ± 0.02 g, initial weight). Fish were fed 15 diets containing 5 DPs (350, 400, 450, 500 and 550 g/kg) and 3 DLs (60, 90 and 120 g/kg) for 8 weeks. The interaction between proteins and lipids significantly influenced the feed conversion ratio, condition factor, body composition, antioxidant indices and lipase activity (p < .05). DP 450 g/kg showed the highest average final body weight. DPs 500 and 550 g/kg significantly decreased the protein efficiency ratio (p < .05). DL 120 g/kg showed the highest percentage weight gain. The low feed conversion ratio was found in diets P45L12, P55L9 and P55L12. Diet P45L12 showed high superoxide dismutase activities. DP 450 g/kg showed the lowest average malondialdehyde content. Lipase activity was increased by increasing DP (p < .05) with a fall at DP 550 g/kg. Under the present experimental conditions, the optimal DP for S. sihama was 450 g/kg under the DL 120 g/kg. 相似文献
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William King V David L. Berlinsky Craig V. Sullivan 《Fish physiology and biochemistry》1995,14(6):489-500
Plasma estradiol-17 (E2), testosterone (T), 17,20-dihydroxy-4-pregnen-3-one (DHP) and 17,20,21-tri-hydroxy-4-pregnen-3-one (20-S) levels were measured by radioimmunoassay (RIA) in white perch (Morone americana) and white bass (M. chrysops) that were induced to undergo final oocyte maturation (FOM) with human chorionic gonadotropin (hCG). Plasma DHP levels increased in females of both species in association with oocyte germinal vesicle migration (GVM) and germinal vesicle breakdown (GVBD) and decreased thereafter. Plasma 20-S levels also increased with oocyte GVM in white bass, but were several-fold lower than DHP levels. Circulating E2 and T levels were greatest during GVM and GVBD in both species and decreased to low levels during oocyte hydration and ovulation. Follicles from white perch and white bass which received a priming injection of hCG in vivo, produced both DHP and 20-S in vitro after exposure to hCG and their oocytes underwent GVBD. Ovarian incubates from unprimed fish of either species produced only E2 and T and their oocytes did not complete GVBD. Oocytes from unprimed bass, but not perch, matured when follicles were exposed to hCG in vitro. Both trilostane and cycloheximide blocked in vitro production of DHP and 20-S and oocyte GVBD by white perch follices. DHP and 20-S were equipotent inducers of FOM in the GVBD bioassay. None of several other structurally-related steroids tested were effective within a physiological range of concentrations. These results indicate a role for DHP and 20-S in the control of FOM in white perch and white bass. 相似文献