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黑龙江水系(中国)大麻哈鱼生物学特征分析 总被引：1，自引：0，他引：1
2010和2011年在黑龙江和乌苏里江生殖洄游群体中采集了571尾大麻哈鱼(Oncorhynchus keta Walbaum)样本,进行了鳞片观察和生物学测定。根据退算叉长,采用Logistic生长方程拟合大麻哈鱼叉长的生长,并计算了生长速度和加速度。结果表明,大麻哈鱼3龄前生长速度较快,以后逐渐变慢。对3+龄大麻哈鱼生长分析表明,在1.372和1.492龄时,雄、雌个体生长速度最快,而在2.674和2.823龄时生长加速度最低,和性成熟开始时期相吻合。利用逻辑斯蒂拟合方程估算了大麻哈鱼50%个体初次性成熟叉长(L50),雄性为46.19 cm,雌性为47.95 cm,ARSS分析表明雌雄差异显著(P<0.05),对应的50%初次性成熟时间T50分别为2.00和2.15。通过大麻哈鱼生长分析,认为应将50%初次性成熟叉长作为资源管理的重要生物学指标。黑龙江大麻哈鱼雌性个体GSI和绝对繁殖力均与叉长呈显著正相关(P<0.05),而雄性个体上述指标均与叉长呈显著负相关(P<0.05)。黑龙江雌性和雄性大麻哈鱼GSI与叉长相关关系的回归方程分别为:y=0.578x–18.225(R2=0.441);y=–0.090x+8.852(R2=0.423)。黑龙江群体性腺发育程度高于乌苏里江群体,乌苏里江群体性腺发育的不一致性导致了GSI和叉长的相关关系不显著。 相似文献
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本文对628尾图们江马苏大麻哈鱼陆封型的一些生物学资料进行研究。结果表明鱼群由1—6龄组成，主要是2—4龄。我们首次发现雌鱼绝大多数个体(99．4％)终生不性成熟，性腺滞于Ⅱ期，故他们自繁能力极低。陆封型与洄游型关系密切。他们的产卵期与产卵场环境相同，前者雌雄比为1：1．7，后者为8：1，前者雄鱼参与后者繁殖，其性比恰呈互补，主食落入水中的陆生昆虫。建议保护陆封型资源。 相似文献
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根据2011年3月至2012年1月在长江天鹅洲故道采集的银鮈(Squalidus argentatus)样本873尾,用鳞片为年龄鉴定和生长退算材料,研究银鮈的年龄、生长特性及死亡率.结果表明,雌雄群体均由1～6龄组成,雌鱼87.35％为1～3龄,雄鱼87.01％为1～3龄.雌雄鱼体长(L)和体重(W)关系表现为异速生长,雌鱼w=0.009L3.2285,雄鱼w=0.009L3.2254.以退算体长拟合von Bertalanffy方程,得到生长参数为:雌鱼L∞=17.1797cm,k=0.1820,t0=-1.2673和雄鱼L∞=11.5069cm,k=0.4074,to=-0.5764.雌雄鱼的自然死亡率分别为M=0.6048/a和M=1.1459/a,远高于一般鱼群自然死亡率(M=0.2～0.3/a);开发率分别为E=0.5711和E =0.4183.长江天鹅洲故道银鮈雌鱼处于过度开发的状态,应加强管理. 相似文献
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2011年9月,在北江采集鲂(Megalobrama skolkovii)样本326尾,以鳞片作为年龄鉴定材料,进行年龄与生长的研究。研究结果显示:鲂渔获物由2～7龄组成,3～5龄为优势年龄组,占渔获总量的87.42%;优势组体长为190～270 mm,占渔获物的44.79%;体质量集中在100～800 g,占渔获物的70.25%。体长鳞径呈线性相关,雌鱼:L=44.281R+16.927;雄鱼:L=41.483R+23.732。体长体质量呈现幂函数关系,雌鱼:W=4×10-5L2.950 2,雄鱼:W=5×10-5L2.871 7,生长均属于等速生长型。北江鲂生长符合Von Bertalanffy方程,雌鱼:Lt=480.52(1-e-0.234 3(t+0.239 5)),雄鱼:Lt=462.05(1-e-0.235 1(t+0.306 2));雌鱼:Wt=3052.92(1-e-0.234 3(t+0.239 5))2.950 2,雄鱼:Wt=2400.78(1-e-0.235 1(t+0.306 2))2.871 7,雌鱼生长快于雄鱼,且寿命更长。研究认为:北江鲂资源呈现低龄化的趋势,为可持续开发利用,建议限定捕捞规格为300 mm(700 g)以上。 相似文献
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20 0 3年 4～ 5月对乌苏里江下游海青江段黑斑狗鱼采捕 2 48尾标本挂网渔获物进行渔业生物学研究。挂网捕捞群体体长由 3 5～ 85cm组成 ,平均为 5 3cm ;体重由 2 3 0～ 5 2 5 0 g组成 ,平均为 1 95 7g ;年龄由 1～ 5龄组成 ,平均为 2 .2龄 ;绝对生殖力由 92 82～ 1 1 5 5 0粒组成 ,平均为 1 0 41 6粒 ,相对生殖力由 1 5 .3 5～ 2 9.5 9粒 /g组成 ,平均为 2 2 .99粒 /g ;成熟系数 ( 4～ 5月 )雌群由 0 .3 7%～ 2 2 .5 2 %组成 ,平均为 1 8.5 8% ;雄群由 0 .69%～ 2 .1 7%组成 ,平均为 1 .49% ;肥满度系数 4～ 5月雌群由 0 .41 3 0 %～ 2 .0 0… 相似文献
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2001-2009年在黄河上游水系进行土著鱼类资源调查,对收集到的235尾厚唇裸重唇鱼开展繁殖生物学研究。研究发现,厚唇裸重唇鱼繁殖期为4-6月,盛期为5月,在繁殖季节可借第二性征辨别性别,雌鱼和雄鱼均于6龄达到性成熟,雌鱼最小性成熟体长30.8cm,体质量380.7g,成熟系数15.21%;雄鱼体长27.2cm,体质量335.7g,成熟系数10.18%。厚唇裸重唇鱼绝对怀卵量为3043～42 158粒,相对怀卵量为7.9～37.2粒/g。成熟卵径(2.1±0.1)mm,卵子数为134.9粒/g;测定了产卵场的理化因子,集群繁殖需要约8℃的水温及其他一些生态因子刺激(海拔、水流、饵料等)。 相似文献
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2011-2012年在乌江思南江段采集454尾(雌性298尾,雄性109尾,性别不辨47尾)泉水鱼(Pseudogyrincheilus procheilus),以鳞片作为材料对年龄进行鉴定,利用软件FISAT-II处理体长与年龄数据,对其生长方程、生长拐点等生物学特征进行了研究。结果表明,泉水鱼鳞片为圆鳞,年轮主要表现为普通切割型与普通疏密型;年龄组成为1~4龄,其中以2~3龄为主;1~4龄,体长增长率为47.4%,雌性体长增长率达50.4%,雄性体长增长率为35.0%,体重增长率为438.5%,雌性体重增长率为485.1%,雄性体重增长率为275.9%;体重(W)与体长(L)呈幂指数关系:W=2×10-6L3.4784(R2=0.8824),雌鱼为:W=3×10-6L3.4002(R2=0.8505),雄鱼为:W=2×10-5L3.019(R2=0.8112);体长(L)和鳞径(S)呈幂函数相关:L=92.597S0.5458;Von Bertalanfy生长方程的各参数为:渐进体长L∞=278.10 mm,生长系数k=0.22,t0=-1.80;雌鱼各参数为:L∞=355.01 mm,k=0.14,t0=-2.38;雄鱼各参数为:L∞=224.04 mm,k=0.32,t0=-1.72,雄鱼达到渐进体长的速度比雌鱼要快得多;体长生长速度和加速度不具拐点,生长速度随年龄增加而递减,生长加速度始终为负值,随年龄增加而增大;体重生长速度和加速度都具有拐点,拐点年龄ti=3.87,拐点体长Li=198.22 mm,拐点体重Wi=195.59 g。结合泉水鱼生长拐点年龄和性成熟年龄,为保护乌江思南泉水鱼资源,建议以180 mm为最小捕捞个体的体长。 相似文献
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施氏鲟（AcipenserSchrenckiBrandt）又称史氏鳄、黑龙江综,是目前世界26种鳄村鱼类中的一一种,和国家一级保护动物中华的同属一类,只分布在黑龙江水域。它是淡水鱼中个体大寿命长的种类,在黑龙江里捕捞的个体一般体长l一2米,体重5－25公斤,l（1－2龄。性成熟晚,雌鱼9－13龄,雄鱼7－9龄。每年的6－7月是它繁殖后代的季节。此时它们成群结队地从黑龙江下游向中游的产卵场挺进,其它个体较小的鱼类早已躲得无影无踪了。鲍鱼是淡水色中的八块头,老寿星,在波涛汹涌的大江中畅游无阻,而且幼鱼的观赏性很强,开始受到观赏鱼爱好者的… 相似文献
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对闽南近海条纹斑竹鲨的生殖生物学进行了初步研究,结果表明,闽南近海条纹斑竹鲨雌鱼和雄鱼的性成熟年龄均为3龄;雄鱼群体性成熟的高峰期是9～11月,雌鱼群体的性成熟高峰期是12月至翌年4月,交配高峰期是12月至翌年3月,生殖高峰期是5～6月;闽南近海条纹斑竹鲨的生殖周期为一年,一个生殖周期内,一尾雌鱼受精后从开始产受精卵到完全排完受精卵历时大约2个月,可以产约30个受精卵. 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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Growth hormone (GH) and reproduction: a review 总被引：5，自引：0，他引：5
Florence Le Gac Odile Blaise Alex Fostier Pierre-Yves Le Bail Maurice Loir Brigitte Mourot Claudine Weil 《Fish physiology and biochemistry》1993,11(1-6):219-232
Interaction between growth and reproduction occurs in many vertebrates and is particularly obvious at certain stages of the life cycle in fish. Endocrine interactions between the gonadotropic axis and the somatotropic axis are described, the potential role of GH being emphasised. A comparative analysis of these phenomena in mammals, amphibians and fish, suggests a specific role of GH in the physiology of puberty, gametogenesis and fertility. It also shows the original contribution made by studies on the fish model in this field of investigations. 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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