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1.
2012年3月–2014年12月对长江上游宜宾江段采集的521尾野生长鳍吻鮈进行了繁殖生物学研究。结果显示,长鳍吻鮈种群雌雄比为1.41:1,繁殖期为3–5月,盛期为4月上旬至5月上旬。繁殖季节可通过吻端细小"珠星"鉴别雌雄,雄鱼最小性成熟年龄为2~+龄,最小成熟体长为173 mm,体重为90.4 g,成熟系数为0.36%;雌鱼最小性成熟年龄为3~+龄,最小成熟体长为185 mm,体重为119.6 g,成熟系数为11.30%。繁殖群体中,雌性优势龄组为3~+龄,雄性优势龄组为2~+龄和3~+龄。统计结果显示,长鳍吻鮈绝对繁殖力(F)为16399–39835(26816±7875)粒/尾,体重相对繁殖力(F_W)为162–234(189±23)粒/g,体长相对繁殖力(F_L)为877–1659(1231±246)粒/cm。通过对性腺成熟系数、卵径分布频率以及性腺组织切片结果的综合分析认为,长鳍吻鮈属于完全同步产卵类型。  相似文献   

2.
2013和2014年5~6月间,采用自制悬挂式电鱼机,在鸭绿江支流蒲石河采捕368尾杂色杜父鱼Cottus poecilopus Heckel,研究该鱼的生物学。结果表明:杂色杜父鱼全长L(mm)与体质量W(g)的关系式为:W=2×10-5L2.9662。48尾雌性个体的统计表明,个体绝对繁殖力(F)为497粒,体长相对繁殖力(FL)为5.06±2.13粒/mm,体质量相对繁殖力(FW)为36.98±15.63粒/g。杂色杜父鱼的摄食率为28.26%;充塞度为1~5级的标本尾数分别占总标本数的38.46%、26.92%、19.23%、11.54%,和3.85%;主要食物为底栖动物和小型鱼类。饵料生物中个数百分比(N%)最高的种类是灰纹石蛾Hydropsyche ulmeri,质量百分比(W%)和出现频次百分比(F%)最高的均为钩虾Gammarus sp.,百分比相对重要性指数(IRI%)最高的是灰纹石蛾Hydropsyche ulmeri。  相似文献   

3.
2018年6—7月,在乌苏里江抚远江段采集了284尾东北鳈Sarcocheilichthys lacustris,研究其生物学体征、种群年龄组成及繁殖力。结果表明:284尾东北鳈中有雌鱼226尾、雄鱼58尾,雌雄比例为3.9∶1;年龄范围1~5龄,3~4龄年龄组个体为优势年龄组,占总样本量的68%;性腺成熟系数(GSI)为(11.27±5.62)%,绝对繁殖力(F)为(5924.69±2177.01)粒,相对繁殖力(F1)为(60.81±15.25)粒/g,体长相对繁殖力(FL)为(33.02±10.66)粒/mm,体质量相对繁殖力(FW)为(49.41±11.61)粒/g;个体绝对繁殖力与体长(L)、体质量(W)及GSI的关系分别为:F=1170.8L-2.6L2-119577,F=320.65W-0.9W2-18919,F=143.89GSI1.452。  相似文献   

4.
黑龙江乌苏里白鲑的个体繁殖力   总被引：1，自引：0，他引：1  
2013年和2014年的10–11月,在黑龙江抚远江段采集成熟度为IV期的雌性乌苏里白鲑(Coregonus ussurinsis)133尾,鉴定年龄(A),测量叉长(L)、体重(W)、净体重(Wn)和卵巢重(Wo)等生物学指标。计算了绝对繁殖力(F)、叉长相对繁殖力(FL)、体重相对繁殖力(FW)、性成熟系数(GSI)和肥满度(K),并运用6种数学模型及多元线性逐步回归方程拟合了乌苏里白鲑个体繁殖力与生物学指标之间的关系。结果表明,用于统计繁殖力的样本由4+~8+龄5个年龄组组成,乌苏里白鲑F分布范围在1.161×104~5.921×104粒,平均为3.027×104粒;FL分布在307.13~1119.4 eggs/cm,平均为622.5 eggs/cm;FW分布在19.81~56.98 eggs/g,平均为34.62 eggs/g。F与叉长、体重和年龄拟合度最高的函数分别为幂函数、线性函数和抛物线,FL与叉长、体重和年龄分别为幂函数、幂函数和线性函数相关,而FW与叉长、体重和年龄无显著相关性,FW只与卵巢重和性成熟系数具有一定的相关性,且拟合度最高的方程均为幂函数。多元线性逐步回归分析表明,乌苏里白鲑F与卵巢重、叉长和性成熟系数显著相关,而FL和FW均受卵巢重和性成熟系数的显著影响,从二者偏相关系数值来讲,卵巢重与个体繁殖力(F、FL、FW)之间的相关性均高于性成熟系数。  相似文献   

5.
长江中游贝氏(鳖)繁殖生物学研究   总被引：1，自引：0，他引：1  
2016年4-12月在监利长江何王庙故道采集591尾样本,对长江中游贝氏(鳖)(Hemiculter bleekeri)性比、初次性成熟大小、繁殖季节、产卵类型、产卵群体组成及繁殖力等繁殖生物学指标进行了分析.结果显示:贝氏(鳖)总体雌雄性比1.44:1,与1:1存在极显著性差异;繁殖期间雌雄比2.5:1,非繁殖季节雌雄比为0.91:1.繁殖群体年龄结构为1-3龄,以1龄补充群体为主,属于第Ⅱ类型.初次性成熟体长:SL♀50=8.08 cm, SL♂50=8.47 cm,最小观测性成熟个体分别为:雌性7.5 cm,体重6.65 g, 1龄;雄性8.2 cm,体重8.13 g, 1龄.根据成熟系数变化和性腺发育期观察,推测其繁殖季节为4-6月,可能延至7月份.贝氏(鳖)绝对繁殖力为1703~9601粒/尾,平均为(5876.6 ± 1837.8) 粒/尾,与体重、性腺重均呈线性关系,与体长呈幂函数关系.相对繁殖力(FW)为204.7~406.5粒/g,平均(322.3 ± 49.7) 粒/g,与成熟系数呈幂函数相关;相对繁殖力(FL)为212.0~827.6粒/cm,平均(552.4 ± 136.1) 粒/cm,与体重幂函数相关.  相似文献   

6.
2016年4-12月在监利长江何王庙故道采集591尾样本,对长江中游贝氏(Hemiculter bleekeri)性比、初次性成熟大小、繁殖季节、产卵类型、产卵群体组成及繁殖力等繁殖生物学指标进行了分析。结果显示:贝氏总体雌雄性比1.44∶1,与1∶1存在极显著性差异;繁殖期间雌雄比2.5∶1,非繁殖季节雌雄比为0.91∶1。繁殖群体年龄结构为1-3龄,以1龄补充群体为主,属于第Ⅱ类型。初次性成熟体长:SL♀50=8.08 cm,SL♂50=8.47 cm,最小观测性成熟个体分别为:雌性7.5 cm,体重6.65 g,1龄;雄性8.2 cm,体重8.13 g,1龄。根据成熟系数变化和性腺发育期观察,推测其繁殖季节为4-6月,可能延至7月份。贝氏绝对繁殖力为1 703~9 601粒/尾,平均为(5 876.6±1 837.8)粒/尾,与体重、性腺重均呈线性关系,与体长呈幂函数关系。相对繁殖力(FW)为204.7~406.5粒/g,平均(322.3±49.7)粒/g,与成熟系数呈幂函数相关;相对繁殖力(FL)为212.0~827.6粒/cm,平均(552.4±136.1)粒/cm,与体重幂函数相关。  相似文献   

7.
长江干流长鳍吻鮈(Rhinogobio ventralis)繁殖生物学   总被引：1，自引：0，他引：1       下载免费PDF全文
2012年3月-2014年12月对长江上游宜宾江段采集的521尾野生长鳍吻(鱼句)进行了繁殖生物学研究.结果显示,长鳍吻(鱼句)种群雌雄比为1.41∶1,繁殖期为3-5月,盛期为4月上旬至5月上旬.繁殖季节可通过吻端细小“珠星”鉴别雌雄,雄鱼最小性成熟年龄为2+龄,最小成熟体长为173 mm,体重为90.4 g,成熟系数为0.36％;雌鱼最小性成熟年龄为3+龄,最小成熟体长为185 mm,体重为119.6 g,成熟系数为11.30％.繁殖群体中,雌性优势龄组为3+龄,雄性优势龄组为2+龄和3+龄.统计结果显示,长鳍吻(鱼句)绝对繁殖力(F)为16399-39835(26816±7875)粒/尾,体重相对繁殖力(FW)为162-234(189±23)粒/g,体长相对繁殖力(FL)为877-1659(1231±246)粒/cm.通过对性腺成熟系数、卵径分布频率以及性腺组织切片结果的综合分析认为,长鳍吻(鱼句)属于完全同步产卵类型.  相似文献   

8.
于2015年5~6月在辽河双台子河口水域采捕176尾性腺发育到Ⅳ期的刀鲚Coilia nasus雌鱼,测量其体长(L)、体质量(W)、净体质量(W_o)、性腺重(W_l)和卵径等生物学指标。取左侧鳃盖骨鉴定年龄,用重量法计数个体绝对生殖力(F),计算体长相对生殖力(F_L)和体重相对生殖力(F_w),用5种数学模型及多元逐步回归方程拟合个体生殖力与生物学指标的关系。结果显示:样本由4~+~6~+龄组成,个体绝对生殖力(F)17 968~116 935粒,平均44 995粒;体长相对生殖力(F_L)66~297粒/mm,平均为145粒/mm;体质量相对生殖力(F_w)192~710粒/g,平均为362粒/g。F和F_L与体长(L)、体质量(W)、净体质量(W_o)、性腺重(W_l)、成熟系数(GSI)和年龄呈极显著正相关,与肥满度(K)相关关系不显著。F_w仅与W_l、GSI极显著正相关,和其他指标的相关性不显著。多元逐步回归显示,F与W和W_l密切相关,相关式为:F=-15 623.878+1 158.377W_l+324.104W(n=176,R=0.851;DW=1.890,P0.01);F_L与W_l和K密切相关,相关式为:F_L=-68.850+3.868W_l+302 687.076K(n=176,R=0.728;DW=1.743,P0.01);F_w均与L和GSI密切相关,相关式为:F_w=207.215-5.17L+7.5918GSI(n=176,R=0.646;DW=1.849,P0.01)。第Ⅳ~Ⅴ期刀鲚卵巢中,卵径变化范围在0.55~1.05mm之间,平均0.81mm。依据卵径频率分布推测,刀鲚属单峰一次性产卵鱼类。  相似文献   

9.
2012~2015年在长江上游宜宾江段采集样品,分析研究长鳍吻鮈Rhinogobio ventralis的个体繁殖力及其与各体征指标的关系。结果表明:长鳍吻鮈的绝对繁殖力(F)变动范围为16 399~40 021粒/尾,平均为(27 943±7 777)粒/尾;体长相对繁殖力(FL)变动范围为87~165粒/mm,平均为(120.9±19.8)粒/mm;体质量相对繁殖力(FW)变动范围为124~234粒/g,平均为(163.8±21.7)粒/g。繁殖力与体征指标的相关分析表明:F、FL与体长、体质量、净体质量、卵巢质量以及年龄均呈正相关,达到极显著水平(P0.01);FW仅与体质量、净体质量以及成熟系数显著相关(P0.01);进一步回归分析显示:F、FL与体长、体质量、净体质量均呈二次函数相关,即繁殖力随体长、体质量增加而增长。  相似文献   

10.
研究长江宜昌江段鳙(Aristichthys nobilis)野生群体的性比、年龄结构、初次性成熟体长、繁殖力和产卵类型等生活史特征,为三峡水库生态调度方案的优化、鳙增殖放流和人工繁殖提供科学数据。2015年3月至2016年5月,在长江中游宜昌江段月度采样,共收集鳙样本940尾,其中可区分性别个体135尾(♀68尾,♂67尾)。性腺发育达到IV期及以上个体共计55尾,其中雌鱼32尾、雄鱼23尾。繁殖群体雌雄性比为1.4∶1,体长370～900 mm,体重500～11 650 g,由2～7龄共6个年龄组组成。采用Logistic方程推算出初次性成熟个体特征,雌性平均体长480.1 mm,对应体重2 137.6 g,平均年龄3.33龄;雄性平均体长464.0 mm,对应体重1 937.5 g,平均年龄2.91龄。卵径(3.75±0.14) mm,大小分布呈双峰型,推测为分批同步产卵型鱼类。绝对繁殖力(390 000±79 000)粒,相对繁殖力为(72.4±3.0)粒/g,绝对繁殖力随着鱼体长、体重增长而增大。性腺成熟系数周年变化规律显示,宜昌江段鳙的繁殖时间为5月下旬至8月上旬,以6-7月为盛产期。建议提高鳙开捕年龄,严格限制捕捞未性成熟个体;同时加强产卵场的修复和栖息地的保护,并定期实施合理的增殖放流和生态调度。  相似文献   

11.
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   

12.
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   

13.
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14.
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   

15.
Growth hormone (GH) and reproduction: a review   总被引：5，自引：0，他引：5  
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   

16.
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   

17.
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   

18.
Protein and amino acid composition of the mantle of juvenile O ctopus vulgaris (Cuvier, 1797) during fasting for 27 days were determined. Average protein content of octopus mantle was of 711.19 ± 46.80 g kg?1 DW, and it decreased with increasing fasting days. The non‐essential amino acids content was higher (486.18 ± 11.08 g kg?1 protein) than essential amino acids (425.82 ± 9.15 g kg?1 protein) at the start of the experiment (unstarved animals). The results suggest that the amino acid profile of the mantle where the most abundant amino acids are Arg, His, Lys, Gly, Leu and Pro could indicate a prolonged fasting condition (>20 days) or poor nutrition of O . vulgaris. This study supports the idea of using mantle for metabolic needs of starved O . vulgaris suggesting that the degradation pathway of amino acids to pyruvate and tricarboxylic acid cycle intermediates was favoured contrary to the degradation pathway of ketogenic amino acids. Special considerations should be taken concerning Thr, Ile, Ser, Ala, Asx (Asp, Asn), Glx (Glu, Gln) (because of their fast intake) and Lys and His (due to their stable contents) during a prolonged period of fasting.  相似文献   

19.
The endemic, anadromous cyprinidChalcalburnus tarichi is the only fish species known to occur in alkaline Lake Van (Eastern Anatolia, Turkey). EightC. tarichi were maintained individually in Lake Van water (17 – 19°C; pH 9.8; 153 mEq·I–1 total alkalinity; 22 total salinity) and tank water samples analyzed for 24 h in 2 to 4 h intervals. At zero time, < 1µM ammonia was present and urea was undetectable in the tank water; at 24 h, total ammonia and urea made up 114±32 and 35±25µM, respectively. Over the experimental period, ammonia-N and urea-N excretion averaged 1041±494 and 607±169moles·kg–1 fish·h–1, respectively. The extent of urea excretion was highly variable between specimens. Uric acid excretion was not detectable.Urea was present at high concentrations in all tissues and plasma (25 – 35moles·g–1·ml–1) of freshly caughtC. tarichi; total ammonia content of the tissues was by a factor of 1.9 (liver) to 3.0 (brain) lower. High arginase activity (2.4±0.2 U·min–1·g–1) was detected in the liver ofC. tarichi but ornithine carbamoylphosphate transferase, a key enzyme of the ornithine-urea-cycle, was absent. Ureagenesis is likely through degradation of arginine and/or uricolysis. High glutamine synthetase activity (11±0.6 U·min–1·g–1) and low ammonia content in brain suggest that, like other teleosts,C. tarichi has an efficient ammonia detoxification in the brain, but in no other tissue.Nitrogenous waste excretion at alkaline pH is discussed. The ability ofC. tarichi to excrete high levels of ammonia at extremely alkaline pH is unique among teleosts studied so far. The mechanism of ammonia excretion under Lake Van conditions remains to be elucidated.  相似文献   

20.
There has been growing concern about the overuse of antibiotics in the ornamental fish industry and its possible effect on the increasing drug resistance in both commensal and pathogenic organisms in these fish. The aim of this study was to carry out an assessment of the diversity of bacteria, including pathogens, in ornamental fish species imported into North America and to assess their antibiotic resistance. Kidney samples were collected from 32 freshwater ornamental fish of various species, which arrived to an importing facility in Portland, Oregon from Colombia, Singapore and Florida. Sixty‐four unique bacterial colonies were isolated and identified by PCR using bacterial 16S primers and DNA sequencing. Multiple isolates were identified as bacteria with potential to cause disease in both fish and humans. The antibiotic resistance profile of each isolate was performed for nine different antibiotics. Among them, cefotaxime (16% resistance among isolates) was the antibiotic associated with more activity, while the least active was tetracycline (77% resistant). Knowing information about the diversity of bacteria in imported ornamental fish, as well as the resistance profiles for the bacteria will be useful in more effectively treating clinical infected fish, and also potential zoonoses in the future.  相似文献   

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