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1.
云南光唇鱼的人工繁殖研究   总被引:4,自引:3,他引:1  
对云南光唇鱼人工繁殖技术和胚胎发育进行了初步的研究。采用鲤鱼脑垂体与释放激素类似物等组成的混合催产剂,在19.8~24.3℃的水温下,效应时间为26~28 h,平均催产率83.3%;在流水中孵化,受精率为77.8%,受精卵经过102 h出膜,184 h仔鱼开始平游,孵化率为41.2%。  相似文献   

2.
泥鳅人工繁殖试验报告   总被引:5,自引:0,他引:5  
闽北地区,4月上旬当水温达到16℃以上时,即可进行泥鳅人工繁殖。试验期催产雌鳅289尾.获产213尾,在水温19—28℃条件下,效应时间为8.5—17h,平均催产率为73.7%,产卵数60.47万粒,平均受精率76.1%,得苗27.21万尾,孵化率为58.6%。文章还就进一步提高泥鳅人工繁殖的“三率”等问题进行了初步探讨。  相似文献   

3.
黑尾近红鲌人工繁殖技术研究   总被引:1,自引:0,他引:1  
为探索黑尾近红鲌的人工繁殖技术,进行了人工催产、受精卵孵化和苗种培育等试验.试验结果表明:在水温25~29 ℃的条件下,给亲鱼一次性注射不同组合的催产剂,其效应时间为9.5~16 h,平均催产率、受精率和孵化率分别为79.47%、85.08%和86.64%;受精卵的孵化时间在36~39 h;试验共获得鱼苗116.82万尾,经40~50 d的培育,育成全长5 cm左右的夏花鱼种35.6万尾,成活率30.47%.  相似文献   

4.
采集钱塘江野生粗唇鮠,在池塘中培育至性成熟,成熟率64.4%.经测定,绝对怀卵量为7200粒/尾,相对怀卵量为49.9 粒/g体重.采用DOM、HCG、LHRH-A2混合催产剂,分两次注射,在25~28℃水温下,分3个批次进行了人工繁殖,共催产亲鱼114组,效应时间为17 h至20 h,催产率83.8%,共获取受精卵46.7万粒;孵化率63.5%,共获得鱼苗26.0万尾,出苗率81.5%;共培育出夏花鱼种17.8万尾,培育成活率68.5%.  相似文献   

5.
欧洲丁(鱼岁)的人工繁殖技术   总被引:1,自引:0,他引:1  
欧洲丁(鱼岁)人工繁殖的亲鱼以3~4龄较好,个体要求雌鱼到达400g,雄鱼到达250g以上;催产时间(鹰潭地区)为4月下旬-5月中上旬为好;适宜水温为18~30℃,最适水温为25~28℃,32℃以上时产卵率、受精率和孵化率都较低;催产激素可选择混合激素,剂量为50μg/kg LHRH-A2和5mg/kg DOM合剂;催产方法以两针注射法为好,针距为8~10h;效应时间(水温25℃时)为11~16h;产卵既可自然产卵也可人工授精,孵化一般在网箱中充氧孵化即可,有条件的地方可以实行脱粘后在环道或孵化漕中进行孵化.三年的最高产卵率87%、受精率91%、孵化率93%.  相似文献   

6.
欧洲丁鱥人工繁殖的亲鱼以3~4龄较好,个体要求雌鱼到达400g,雄鱼到达250g以上;催产时间(鹰潭地区)为4月下旬-5月中上旬为好;适宜水温为18~30℃,最适水温为25~28℃,32℃以上时产卵率、受精率和孵化率都较低;催产激素可选择混合激素,剂量为50μg/kg LHRH—A2和5mg/kg DOM合剂;催产方法以两针注射法为好,针距为8~10h;效应时间(水温25℃时)为11—16h;产卵既可自然产卵也可人工授精,孵化一般在网箱中充氧孵化即可,有条件的地方可以实行脱粘后在环道或孵化漕中进行孵化。三年的最高产卵率87%、受精率91%、孵化率93%。  相似文献   

7.
瓦氏黄颡鱼人工繁殖技术研究   总被引:2,自引:0,他引:2  
瓦氏黄颡鱼在池塘生态环境条件下人工培育亲鱼、人工繁殖.产卵季节为每年的5中旬~7月上旬,产卵水温为20~30℃,最佳产卵水温为23~28℃,催产效应时间水温20~30℃为40~52小时.流水水泥池中流水孵化,孵化必须在室内光照500~800Lx条件下进行,孵化出膜时间水温20~30℃为47~70小时.人工繁殖的产卵率、受精率、孵化率均达到90%以上.  相似文献   

8.
本文研究了杂交鳢(Channa maculate♀×C.argus♂)的亲鱼斑鳢(C.maculata)培育、杂交鳢人工繁殖、孵化和鱼苗培育等技术。结果显示:斑鳢在杭州地区池塘条件下经人工培育可达性成熟,但无法在自然条件下过冬,需进行保温越冬。杂交鳢人工催产繁殖的适宜水温在22℃以上,以25~28℃为宜。25~30℃水温条件下,分二次注射LHRH-A2、HCG和DOM混合催产剂,其效应时间在32 h以内;采用自然受精,泡沫箱或网箱孵化,其平均催产率为93.3%,平均受精率为72.9%,孵化率为64.1%,孵化时间18~45 h;通过定时过筛、分级分养、适时驯食等技术培育20 d左右,鱼种全长可达3.3~3.8 cm,平均成活率56.5%。  相似文献   

9.
长江大鳍鱯的人工繁殖   总被引:1,自引:0,他引:1       下载免费PDF全文
本文对长江大鳍亲鱼的池塘培育和人工繁殖技术进行了研究。1992年~1994年期间,采用池塘混养技术,将长江野生大鳍引入池塘进行驯化和培育,连续2年获得成熟亲鱼并进行人工繁殖。在池塘环境中,大鳍雌亲鱼成熟率分别为818%和706%,雄亲鱼分别为100%和935%。采用多种催产药物混合注射的催产方法,可以得到较好的催产率。大鳍人工繁殖适宜的催产剂量是雌鱼每g体重注射LRH-A03~05μg、DOM003~005mg和HCG5~10IU,雄鱼减半或同量。水温24~26℃时,催产效应时间为12~13h。受精卵在水温27~29℃时需53~55h孵化出膜。大鳍人工繁殖受精率不高与其雄鱼精巢特殊的组织结构有关。  相似文献   

10.
对长春鳊的人工繁殖进行了初步试验,共收集驯养亲本298kg,分3批催产56组。先用2μgLRH-A3预备针催熟,再用2mgDOM+8μg LRH-A3+800 IU HCG混合催产,产卵66.8万粒,受精率达84%,水温在24~27℃,效应时间为22~24h,孵化率达82%。  相似文献   

11.
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.
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   

14.
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   

15.
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   

16.
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   

17.
18.
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   

19.
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   

20.
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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