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1.
养殖中华鲟性腺发生与分化的组织学研究 总被引：15，自引：0，他引：15
用组织切片方法研究人工繁育中华鲟的性腺发生及两性分化过程。中华鲟出膜后3d，原始生殖细胞以单细胞的形式存在于肾管区腹下方。出膜后11d，生殖褶形成，到2月龄和7月龄时，性腺中分别出现血管和脂肪组织，直到8月龄性腺均处于两性未分化状态，划分为0期。9月龄(体重0．6～1．1kg)，性腺出现组织学水平上的两性分化，性腺划入I期。I期性腺中，精(卵)原细胞进行有丝分裂。以初级精(卵)母细胞出现作为Ⅱ期开始的标志，精巢和卵巢分别于1．8～2．2年龄(1.55～5．6kg)和2．5～3．0年龄(3．1～8．2kg)进入Ⅱ期。3年龄以后，性腺发育分化陆续达到肉眼可分辨性别的程度，5～5．6年龄(18～35．5kg)时，所有的性腺能肉眼区分雌雄，但精巢和卵巢仍都处于Ⅱ期，其中卵母细胞的卵径为60～240μm。 相似文献
2.
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
3.
以1981～2004年间捕获的中华鲟(Acipenser sinensis Gray)亲鲟样本为研究材料，研究葛洲坝截流24年来中华鲟繁殖季节中坝下30km范围内产卵群体结构的变化情况。测定与统计结果显示，中华鲟雌雄性比由1981～1983年的1．10：1降低到1987～1989年的0．63：1，而后上升到2003～2004年的5．86：1。雌鲟平均体长由1990～1992年的263．1cm增加到1999～2001年的276．7cm，升幅为5．2％(差异极显著)；平均体重由1990～1992年的202．4kg增加到2003～2004年的237．4kg，升幅为17．3％(差异显著)。雌鲟年龄的平均值在24年中的前9年里(1981～1989年)波动于19．0～20．7龄，在后15年(1990～2004年)里，雌鲟年龄平均值在21．1～22．7龄之间波动，普遍高于前9年中的年龄平均值。雄鲟群体变化比雌鲟群体变化大。雄鲟平均体长、体重分别由1981～1983年的205．1锄、89．8kg下降到1987～1989年的197．5cm、72．7kg(降幅分别为3．7％、19．0％)，然后上升到2003～2004年的229．4锄、121．1kg(升幅分别为16．4％、65．2％)；平均年龄由1981～1983年的15．4龄下降到1987～1989年的13．3龄(降幅为13．6％)，然后上升到1996～1998年的17．6龄(升幅32．3％)。在1993～2004年中华鲟产卵场采集并鉴定了年龄的中华鲟亲鲟中，共发现28尾1981～1989年出生的个体即葛洲坝截流后出生的个体，这证明了在洄游路径缩短622～1166km后，中华鲟的回归本能尚未丧失，同时，由于在葛洲坝截流后的初期并没有实施人工繁殖放流，这佐证了葛洲坝截流后新形成的中华鲟产卵场的有效性。 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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中华鲟全人工繁殖技术研究 总被引：12，自引：3，他引：9
中华鲟(Acipenser sinensis)在人工驯养条件下性腺发育并最终成熟是突破中华鲟全人工繁殖技术的关键环节,有效的养殖模式对促进中华鲟性腺发育成熟、提前成熟以及实现雌雄同步成熟具有非常重要的作用。本研究在不同养殖模式(水温和营养调控)下对中华鲟性腺发育状况进行长期观测。结果显示,中华鲟在仿自然变温或恒温的养殖环境中,性腺均可发育至III期。采用配合饲料、饲料中添加鲜活鱼或冰鲜鱼以及仅用鲜活鱼或冰鲜鱼饲喂,均能够使部分中华鲟性腺发育启动,但添加鲜活鱼或冰鲜鱼组性腺发育启动的比例较高,其中,有3尾中华鲟性腺达IV期。成功对性腺发育至IV期的1尾雌鲟(12龄,体质量57 kg)和1尾雄鲟(14龄,体质量64 kg)实施了人工催产和授精,采获卵6.25万粒,精液2 850 mL,受精率为60.1%(36.3%~80.4%)。在(19.3±0.2)℃下经过约125 h,仔鱼大量孵出,获初孵仔鱼2.3万余尾。此次中华鲟全人工繁殖技术研究的有效尝试可为今后养殖中华鲟的规模化繁育提供借鉴。 相似文献
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史氏鲟南移驯养及生物学的研究:VII人工养殖雄性亲本成功催情试验 总被引：1，自引：0，他引：1
首次获得 4龄全人工养殖性腺成熟雄性史氏鲟亲本 ,试验鱼饲养于装备有循环水系统的长方形水泥池 ,水源为地下井水 ,以人工配合饲料投喂 ,培育过程中适当调整和控制环境条件以及辅以外源激素刺激增进性腺发育。催情试验鱼体长 13 1cm ,体宽 13cm ,体高 13cm ,体重 6 7kg。采用 2针注射法注射激素LHRH -A2 ,效应时间为 2 8 5小时 ,水温 2 2～ 2 3℃。排出高质量精液 110ml,精子被激活后活力为97 1% ,活动寿命达 2 75 6秒 相似文献
7.
二、池养鲶鱼的人工繁殖 (一)鲶亲鱼的培育 1.亲鱼的来源:一种来源于人工繁殖的鲶鱼,在池塘中培育3年达性成熟,体重0.5～1.5kg以上,体长在30cm以上。另一种来源于江河野生鲶鱼,体表无伤,体质健壮,年龄在4年以上,体重0.75kg～1.5kg的鲶鱼为亲鱼。 2.鲶亲鱼产前培育:亲鱼在5月1日前从越冬池捕出后,进行产前一个月左右的强化培育,随着水温的回升,亲鱼加速生长发育,食欲日益旺盛,投喂含蛋白质35％左右的人工颗粒饲料,投喂量为体重的8％。培育期间最好投喂部分动物性饵料或放养部分野生杂鱼。亲鱼培育池面积1～3亩,水源充足,水质符合渔业水质标准,水深1.5m左右,水温在6℃以上时开始投喂少量的颗 相似文献
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叶尔特斯河野生北极茴鱼生物学研究 总被引：1，自引：0，他引：1
2007年8月30日～9月3日,对生活在阿勒泰市富蕴县可可托海镇额尔齐斯河上游支流叶尔特斯河里的野生北极茴鱼进行了野外采样和资源调查,采样距离5 km,采集样本36尾.逐尾进行全长、体长、体重等测量及性腺发育、食性、鱼鳞年龄等观察,并做记录.生物学研究表明:渔获物中1+龄鱼平均体长11.07 cm,平均体重17.67 g;2+龄鱼平均体长17.79 cm,平均体重86.08 g;3+龄鱼平均体长22.48 cm,平均体重196.33 g;性成熟个体3+龄;年龄组成主要为2+龄、3+龄.野生北极茴鱼规格偏小,年龄组成和性成熟年龄均呈现低龄化.野生北极茴鱼秋季摄食旺盛,胃充塞度多为2级和3级,在水温5～8℃时,摄食强度与水温升高呈正比. 相似文献
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《淡水渔业》2021,51(5)
本研究对长丰鲢(Hypophthalmichthys molitrix Changfeng)新品种的性腺发育、性成熟年龄和繁殖力进行了分析,结果显示:1龄长丰鲢的性腺发育不明显,处于Ⅰ期;2龄长丰鲢性腺均处于Ⅱ期,肉眼可分辨雌雄;3龄长丰鲢的性腺处于Ⅲ～Ⅳ期,部分个体发育到Ⅳ期,初次性成熟;4龄长丰鲢的性腺均发育至Ⅳ期,适宜繁殖。长丰鲢雌鱼的最小性成熟年龄为3冬龄,最小体质量为2.20 kg,最小体长为47.40 cm,雄鱼的最小性成熟年龄3龄,最小体质量为2.10 kg,最小体长为52.30 cm。3、4、5、6龄长丰鲢的平均绝对繁殖力分别为617 641、761 167、1 598 551、1 684 025粒,平均相对繁殖力分别为218 616、129 342、215 769、215 657粒/kg;长丰鲢绝对繁殖力和体质量、体长均呈二项式相关。3龄长丰鲢卵径约为983.7μm,而4、5、6龄长丰鲢的平均卵径分别为1 082.6、1 069.2、1 090.0μm;初次性成熟的卵径较小,之后再次性成熟时卵径之间无明显差异。 相似文献
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暗纹东方鲀鱼苗耗氧率和窒息点的初步研究 总被引：2，自引：0，他引：2
对暗纹东方鱼屯两个规格鱼苗的耗氧量、耗氧率和窒息点进行了测定。结果显示 :在水温 31～34℃ ,pH 6 5～ 6 8条件下 ,平均全长 2 36cm、体重 0 4 2 9g的鱼苗 2 4h平均耗氧量 0 32 1mg/ (尾·h) ,耗氧率 1 14 9mg/ (g·h) ,窒息点 1 30 9mg/L ;平均全长 3 4 9cm、体重 0 5 6 9g的鱼苗 2 4h平均耗氧量 0 837mg/ (尾·h) ,耗氧率 0 96 8mg/ (g·h) ,窒息点 1 4 86mg/L。 相似文献
11.
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
20.
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