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1.
低温胁迫对鲤血液学和血清生化指标的影响 总被引：8，自引：3，他引：8
A total of 85 interspecific hybrid F2 (Cyprinus carpiovar. wuyuanensis×Cyprinus pellegrini pellegrini) were cooled to specific temperatures and held at those temperatures over a maximum of 4 days in a waterrecycled and temperaturecontrolled aquarium inside. As a result, the blood homeostasis of experimental fish changed violently as acute temperature changed from 16 ℃ to 10 ℃ and 4 ℃ at a rate of 1 ℃·h-1 according to the data we collected. Whole blood pH, also called extracellular pH (pHe) were very sensitive to temperature changes, where the
re was a significant difference between 10 ℃ (7.41) and 16 ℃ (7.17) (P
<0.01), compared to other values of hematology and serum chemistry. When the water temperature was continually decreased to an extreme temperature of 4℃, the content of Na+ of serum decreased remarkably in comparison with that of 10 ℃ and 16 ℃, which was 85.2 mmol·L-1, 113.3 mmol·L-1 and 118.7 mmol·L-1, respectively. The values of hematology and serum chemistry also altered in gentle temperature changes of (10±2) ℃ and (4±2) ℃. Most values of serum chemistry and pH changed significantly, whereas the values of blood plasma changed slightly. pH was up slowly in 4 days at (10±2) ℃ and down slowly in 3 days at (4±2) ℃. A variety of values of serum chemistry changed remarkably both at (10±2) ℃ and (10±2) ℃, but the values of TP, TG and ALB only changed significantly at (4±2) ℃. These results distinguished at least two mechanisms involved in coldinduced stress in hybrid F2. Coldinduced pH changes resulted in other values altered. What's more, pH correlated negatively with water temperature above 10 ℃, and the content of Na+. We also found that gentle te
mperature changes will be physiologically compensated for on day one at (10±2) ℃ and on day 2 at (4±2) ℃ in hybrid F2. 相似文献
2.
《齐鲁渔业》2014,(6):I0001-I0001
Abstract The effects of diet species,diet density, sizes and temperature on the filtration rate of Mactra veneriformis juveniles were studied in a laboratory system.It was found that the filtration rate of four species microalgae was increased with microalgae density increasing at the optimum microalgae density, but was decreased with the increase to continue.The relationship between filtration rate and individual weight followed an exponential,Y= 13.429X^0.6118（R^2=0.9971）.In addition,the filtration rate was increased with the increase of temperature,but was decreased if the temperature exceeded ℃ ,at which the filtration rate reached the maximum of 2.31ml/ ind.min. 相似文献
3.
The effect of waterborne selenite levels on selenium accumulated by different developmental stages of rainbow trout (Salmo gairdneri) was studied using75SeO
3
=
as a tracer. All stages readily accumulated selenium at both high and low concentrations, but the rate of accumulation increased
as the trout developed from the egg to the juvenile feeding stage. The low rate of selenium accumulation by embryos seemed
to be related more to a lack of gills than to the presence of a chorion. The bioconcentration factor (the ratio of tissue-to-water
concentrations) declined in all groups with increased waterborne selenium levels; accumulation rates appeared limited by cell
permeability. At low levels of waterborne selenium (0.4μg/l), the total accumulated was small relative to existing body burdens and unlikely to contribute significantly to the nutritional
requirement for selenium. High levels (45.6μg/l), however, caused considerable selenium accumulation and may be sufficient to overcome the effects of low dietary selenium. 相似文献
4.
我国赤潮频发现象分析与海藻栽培生物修复作用 总被引：11，自引：1，他引：11
In this paper, the history, main events and present status of red tide
(HAB, harmful algal blooms) along China coast in recent years were reviewed and presented. It showed that the HAB's frequency and scale, number of HAB spec
ies, percentage of toxic HAB events and the degree of damages to marine environment and economy have sharply increased in China since 1960's.
Eutrophication was key factor for high occurrence of red tide. In this paper, main causes of frequent HAB occurrence along China coast was discussed. Many factors might influence the occurrence of red tide, which included weather, climate, coastal current, tidal current, water temperature, salinity, hydrodynamic and nutrient conditions, trace metals and the variation of biological environment. Numerous evidences from all over the world revealed the linkage between the increases in nutrient loading and the occurrences of high biomass blooms. Eutrophication was one of the important causes that involved in high occurrence of HAB. The main sources of nutrients potentially stimulating HABs included terrestrial runoff, aquaculture selfpollution, atmospheric deposition, sea projects and other pollution events in the ocean. Studies showed that the input from land contaminations and the selfpollution of marine aquaculture accelerated eutrophication in coastal waters and were also important impact factors on red tide. Researches suggested that nutrient composition could affect the species composition of phytoplankton as well as the development of some HABs. The changes in nutrient supply ratios, primarily N∶P, often resulted in shifts in red tide species composition. The correlation between cysts and formation of HAB was discussed from the viewpoi
nt of transformation of cyst and vegetative cell, the effects of trace elements and other organic substances on the occurrence of HAB were presented also. It indicated that the nutrient control could be an effective way to reduce the risk of red tide occurrence. Seaweed would play an important role for decreasing marine eutrophication. Among the different methods of red tide controlling studied, seaweed biomass has received much attention due to the cost saving, low sensitivity to environmental and impurity factors, the possible contaminant recovery from the biomaterial and its elevated adsorption capacity. Cultivated seaweeds have very high rates of productivity higher than that of seaweed in its natural habits and grow well in water bodies with higher nitrogen and other nutrients. Seaweeds are able to absorb large quantities of nitrogen, phosphorus and carbon dioxide, produce large quanti
ties of oxygen, and have excellent effect on decreasing eutrophication. Large amounts of C, N and P are accumulated into seaweed tissues as they accumulate considerable biomass over a period of months or years depending on the cultivation season. When seaweeds are harvested, nutrients are removed from the sea area. An investigation was carried out for inorganic nitrogen and inorganic phosphorus concentration at Lusi Coast, Qidong County, Jiangsu Province in China, where there were about 270 hm2 for Porphyra yezoensis cultivation with eutrophic sea water in recent years. While during Porphyra yezoensis cultivation, from Sep 2003 to May 2004, the concentration of ammonium nitrogen declined form 0.511-0.778 mg·L-1 to 0.006-0.057 mg·L-1, nitrite nitrogen concentration declined from 0.010-0.040 mg·L-1 to 0.001-0.009 mg·L-1, and nitrate nitrogen concentration declined from 0.466-0.549 mg·L-1 to 0.286-0.0568 mg·L-1, the average concentration of inorganic phosphorus declined from 0.024 mg·L-1 to 0.019 mg·L-1. Furthermore, during five hours, the concentration of ammonium nitrogen in the seawater declined form 220.88 μmol·L-1 to 8.59 μmol·L-1 by cultivated Gracilaria lemanaiformis, and the concentration of ammonium nitrogen declined form 213.84 μmol·L-1 to zero by cultivated Enteromorpha clathrata. Other bioremediation mechanisms of seaweed inhibiting the red tide microalgae such as nutrients competition and allelopathic effects were also discussed. 相似文献
5.
线纹尖塘鳢的形态生物学与核型 总被引：6，自引：0，他引：6
This paper reports the morphological character and karyotype of Oxyeleotris lineolatus. Oxyeleotris lineolatus is native in Australia and call
ed sleepy cod. It belongs to Oxyeleotris, Eleotridae, Gobioidei, Perciformes in taxonomy. Recently, it was introduced to China and local people were not familiar with it. So we carried out this study. 30 individuals have been observed and some data were recorded. It has a large mouth that is in front and up. The mandible stands out and is longer than the up jaw. There are many rows of thin teeth in up and down jaws. The pelvie fins are located in chest and pectoral fins are large and fanlike. There are two dorsal fins. The tail fin is circular. Gill rakers are sparse and the number of gill rakers is 8-12+3-4. The gas bladder belongs to physoclistaus and its stomach is strong and I-like. The intestine is thick and short and no pyloric caecas. The length of the digestive path is 48.1％-80.3% of the length of body. Its liver has two lobes and the liver weight is 4.1%-7.2% of the body weight. The digestive organs characters are same as the trait of flesheater fish. Its scale belongs to ctenoid scale and its body surface shows several long lines. There is not lateral line in the body. The number of vertebra is 26-27 and it has 10-11 pairs rib. The number of diploid chromosome is 2n=46 and the karyotype formula is 2sm+8st+36t，NF=48. The relative length of chromosome is from 1.37% to 3.48% and it is continuity. No strange size chromosomes relation to sex was observed. The karyotype of Oxyeleotris lineolatus is similar to that of Oxyeletris marmoratus Bleeker from South East Asia and both of them belong to Oxyeleotri. It testifies the correctness of traditional classification on cytology. 相似文献
6.
盐度对黄鲷胚胎发育及早期仔鱼生长的影响 总被引：16，自引：0，他引：16
The effect of salinity on embryo and early larva development of Dentex tumiforns was discussed. Floating forms of egg in different salinities, optimal salinity for embryonic development and early larva growth was studied. The results showed: 1. In immobile condition, all eggs sank at salinity of 32.0, most of egg ssuspended in the middle of water at 34.0, and all eggs floated on the surface when salinity above 36.0. 2. Eggs did not hatch out at salinity of below 10.0 or above 60.0 and the death time of egg gradually moved up with increase or decline of salinity. Eggs hatched out at salinity range of 15.0 and 50.0, including abnormal larva. There was indistinct difference in speed of embryonic development (about 36-40h) within the salinity of 15.0 and 50.0. However the salinity had a great effect on larval survival after hatching and abnormal rate. The relation between hatching rate and salinity variation showed parabola but abnormal rate showed inverted parabola. The hatching rate was 81%-86% and abnormal rate of yolk sac larva was 27%-30% in suitable salinities of 27.0-39.0. The hatching rate was 89%-91% and abnormal rate was 13%-16% in optimal salinities of 33.0-36.0. The oil ball of abnormal larva was located in the central or front position. With increased extent of salinity, spondyle of larva bended and number of larva with arrhythmia increased. 3. The optimal salinities were 30.0-35.0 based on SAI. The test with SAI showed that SAI of early larvae was 41.25-47.53 at salinities of 30.0-35.0, the yolk and oil ball of 7-8 days larva was completely absorbed with a survival rate of 88%. 相似文献
7.
蚤状溞对海水盐度的耐受力研究 总被引：10，自引：1，他引：9
The reproduction and survival of Daphnia
pulex Straus under salinities of 2,3,4,6,8,10 and 15℃,20℃,25℃ has been stu died.The
results show that the alternate effect of salinity and temperature is o utstanding.The
developmental rate of D.pulex goes up with the increa se of temperature under a certain
salinity,and the total life span reduces with the increase of salinity under a certain
temperature. The optimum salinity-tempe rature combination level is salinity 2 and temp.20℃.The
upper salinity limit of reproduction is 4.After short-term training between 15～25 ℃and
at 25℃,the up per salinity limit of reproduction and survival is 6. 相似文献
8.
鳗源嗜水气单胞菌主要外膜蛋白基因克隆及其表达 总被引：5，自引：0，他引：5
A pair of primers were designed according to the published nucleotide sequence of a putative outer membrane protein gene (omp) of Aeromonas hydrophila . With the specific primers, a target fragment about 1.1 kb was amplified from Aeromonas hydrophila ML316 via PCR .The target fragment was inserted into the linearized pGEM-T easy vector. After enzyme restriction and sequencing analysis,the nucleotide data had been further analyzed by DNAman and ClutalW software. The analysis results showed that the cloned DNA fragment had a longest open reading frame (ORF) of 1035 nt,it predicted to be encoded a 344 aa protein with the molecular weight of 36 kD. Hydrophobicity analysis suggested that the protein was highly hydrophilic, especialy at the first 24 aminoacid, this region could function as signal peptide. The homologious comparison proved the cloned gene had 96% homology to the sequence of the omp gene, and the alignment of the amino acid sequence was 98% . The recombinant plasmid was constructed with the target gene and the expressing vector pGEX-4T-1 and then was transformed into E. coli BL21（DE3）by BamH and Sal I .The fusion protein was expressed under the IPTG inducing condition,and exhibited about 62 kD in size,very close to the predicted molecular weight of GSTMOMP, furthermore,the fusion protein was specifically recognized by antiserum which raised against the major outer membrane protein of AHML316. Considering all these together, it proved that the cloned gene represented the major outer membrane protein gene of AHML316, and the expressed gene products shared identical antigenicity with the natural main outer membrane protein,and also provided technical support for developing an advanced gene engineering vaccine against Aeromonas hydrophila. 相似文献
9.
Concentrations of major seawater ions were monitored in six aquarium tanks at the New Jersey State Aquarium over a three-year
period. The ratios of these ions to chlorinity were compared to those in freshly prepared artificial seawater. The largest
aquarium tank (Ocean Tank) exhibits statistically significant (p<0.01) relative enrichment of potassium, calcium and strontium,
and relative depletion of magnesium and sulphate. The likely source of excess potassium is from potassium iodide added to
prevent goiter in sharks. Based on the excess potassium, a total amount of 650 μmol/kg iodide added over the years was calculated
for the Ocean Tank. The excess calcium observed in several tanks correlates with the presence of concrete or arbonaceous shells
in these tanks. In Ocean Tank, a calcium leaching rate of 6.7 kg/month was calculated. Continuous formation of white carbonaceous
precipitates serves as a sink for magnesium in Ocean Tank, and a magnesium removal rate of 5.1 kg/month was calculated. These
and other results show that concentrations of major ions in artificial seawater aquaria are affected by leaching, precipitation
and addition of food supplements, and these factors should be taken into account when preparing artificial seawater for aquarium
tanks with long water residence time.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
10.
江黄颡鱼卵细胞膜的结构特征 总被引：2，自引：0，他引：2
Using conventional histochemical methods and scanning electron microscope, the egg surface of mature oocyte of Pelteobagrus vachelli was observed. The micropyle is funnel-like and consists of micropylar vestibule and micropylar canal. The opening of micropylar vestibule is about 11.35μm in diameter while entrance of the micropyle to the oocyte is only about 2.6 μm. There are plenty of micropores on the surface near the micropyle. Micropyle might act as an apparatus leading spermatozoa to penetrating an oocyte. Regular cord-like structures between basal membrane (the outermost layer of egg surface) and plasmic membrane (the inner layer of egg surface) are found. These cord-like structures, each about 16.75 to 18.50μm in length, 5μm in diameter, comprised small balls whose diameters vary from 2.18 to 2.5μm and are arranged cornpactly under the basal membrane. These kinds of structures are zona radiata and act as special eggshell. After activation of the oocytes, the cord-like structures would partially transform into mucoprotein. To our best knowledge, this paper is the fast report on stereo view of the zona radiata of teleost oocyte. 相似文献
11.
为精确定位鲍疱疹病毒(HaHV-1)在宿主不同组织器官中的分布,明确HaHV-1的组织亲嗜性和侵染进程,实验基于环介导等温扩增技术(LAMP)和原位杂交技术建立了HaHV-1的原位LAMP检测方法。利用该方法研究了HaHV-1人工感染实验不同时间节点,病毒在杂色鲍主要器官的分布规律和组织亲嗜性。并对已报道的HaHV-1 LAMP扩增引物进行优化,实现对载玻片上原位固定靶组织内病毒DNA的稳定、特异扩增,筛选最佳显色时间等原位杂交反应条件,最后通过免疫酶标技术分析HaHV-1在组织样本内的分布情况。结果显示,HaHV-1原位LAMP检测方法最适显色时间为60 min。利用该方法对攻毒后24、36、48、60和72 h,HaHV-1在杂色鲍外套膜、鳃、肝胰腺和腹足神经节4种样本的组织分布情况进行检测和分析。病毒阳性信号最早于36 h出现在腹足神经节,48 h在部分外套膜样本中观察到病毒阳性信号,分布局限于外周神经中。在感染实验后期,病毒阳性信号出现在肝胰腺结缔组织中。病毒阳性信号出现的部位常有大量细胞渗出和浸润,渗出的细胞中可见被病毒感染的血淋巴细胞。本研究建立的HaHV-1原位LAMP检... 相似文献
12.
为探索鱼类转铁蛋白基因tf和转铁蛋白受体基因tfr1a的转录调控机制,本实验以团头鲂为研究对象,在其全基因组数据库中获取tf和tfr1a基因序列,对2个基因候选启动子区转录因子结合位点及CpG岛进行预测,通过PCR方法克隆得到tf和tfr1a基因近端启动子区不同长度片段,连接至pGL3-Basic/pEGFP-1载体,瞬时转染入Hela细胞,并采用双荧光素酶报告基因检测系统进行检测。结果发现,团头鲂tf基因启动子区无CpG岛位点,而tfr1a基因启动子区有2个CpG岛位点。成功构建9个tf和10个tfr1a不同长度启动子片段的重组质粒,经双荧光素酶报告基因系统检测发现,tf启动子核心区域为-268^+56 bp,且-1 308^-1 102 bp片段可能存在正调控该基因表达的转录因子结合位点;tfr1a启动子核心区域为-224^+48 bp,且+48^+92 bp可能存在抑制该基因转录的负调控元件,而-1 229^-1 219 bp区域可能存在促进tfr1a基因表达的正调控转录因子结合位点。 相似文献
13.
采用人工催产和干法授精技术,进行了以中华倒刺鲃、倒刺鲃为母本与其父本及黑脊倒刺鲃雄鱼的种间杂交实验,获得4个杂交组合和2个自交组合,在(27±0.5)℃温度条件下,对其F1卵膜径、受精率、孵化率、孵化时间、畸形率、子代早期形态特征与成活率进行了比较,同时,观察了胚胎发育及其异常现象,结果表明:以中华倒刺鲃为母本的F1卵膜径差异不显著;以倒刺鲃为母本的F1卵膜径,在多细胞期时差异不显著,在耳石期时,倒刺鲃♀×中华倒刺鲃♂F1卵膜径显著大于母本(P<0.05)。杂种F1的受精率、孵化时间与母本差异不显著,畸形率显著高于母本(P<0.05)。中华倒刺鲃杂种F1的孵化率较高,与母本差异不显著(P<0.05)。倒刺鲃♀×中华倒刺鲃♂F1的孵化率与母本之间差异不显著,倒刺鲃♀×黑脊倒刺鲃♂F1的孵化率显著低于母本(P<0.05)。中华倒刺鲃杂种F1仔鱼早期发育阶段存在死亡高峰期,成活率显著低于母本(P<0.05)。中华倒刺鲃种间杂交和倒刺鲃♀×黑脊倒刺鲃♂杂种F1既具有父本特征,同时又具有母本特征,初步证明倒刺鲃属种间杂交是可行的。 相似文献
14.
为研究大菱鲆高温胁迫下相关应激基因的表达影响,采用Real-time PCR对本课题组已定位到的大菱鲆高温胁迫应答主效QTL中的4个候选基因(p53、UBE2H、ZNF469和MAGI2基因)在不同温度胁迫下的肝脏、鳃、脾脏、皮肤4个组织中的表达量进行检测。以大菱鲆正常生活水温14°C为对照组,20°C、23°C、25°C和28°C为实验组,进行数据分析。结果显示,4个基因在各个组织中均有表达,且表达量具有组织和温度特异性。其中UBE2H的表达量在4个组织中均呈现出先上升后下降的趋势,在肝脏、脾脏、皮肤组织中20°C时急剧上升并达到峰值且差异显著;在鳃组织中23°C时达峰值,差异显著。p53在4个组织中的表达量均有先上升后下降的趋势,但在鳃和皮肤组织中28°C时表达量急剧升高达到峰值且差异显著。ZNF469和MAGI2在4个组织中均在20°C时大量表达,并远高于其他温度。研究表明,在大菱鲆高温胁迫应答过程中p53基因与DNA修复和细胞凋亡密切相关,而UBE2H基因参与的泛素-蛋白酶体途径对p53基因具有反馈调节作用,是维持细胞稳态的关键基因;ZNF469和MAGI2在作为鱼类应答高温胁迫的生物标志物方面具有重要研究价值。 相似文献
15.
报道了患短钩拟指环虫病欧洲鳗的症状、流行状况和鳃显微组织病理.游动和呼吸频率异常、鳃丝浮肿和鳃上粘液增多为该病的主要症状.该病尽管在冬季也有发生,但水温在26℃以上的春末、夏季和秋初是最易发病的流行季节,流行出现明显的季节性变化.患病欧洲鳗鳃的组织病理变化主要表现出5种类型,其一是鳃小片上皮细胞增生,使邻近的鳃小片相连;其二是鳃小片粘液细胞增生,同样使鳃小片连成一片,增生的粘液细胞经阿利新蓝(Alclan blue)和过碘酸雪夫氏(Periodic acid schiff)二者联合染色后呈蓝紫色的染色反应,属于Ⅳ型的粘液细胞;其三是鳃小片肿大,但单层扁平上皮细胞无肿大现象,上皮细胞层与毛细血管相分离,鳃小片上皮细胞坏死,上皮细胞层破裂,血细胞外溢,鳃小片上皮细胞坏死脱落后,失去鳃小片原有的结构;其四是鳃小片肿大同时伴随单层扁平上皮细胞肿大,进一步发展,鳃小片上皮细胞坏死脱落后,鳃小片同样失去原有的结构;其五是鳃小片毛细血管严重充血扩张,比原毛细血管扩张几倍到十几倍,形成充满红细胞的棒状到球状的动脉瘤.结果表明鳃上皮细胞增生、粘液细胞增生、鳃小片肿大、上皮细胞坏死脱落和严重充血成动脉瘤等病理变化都可导致患病欧洲鳗呼吸困难,轻者影响其生长,重者最终因呼吸衰竭而死亡. 相似文献
16.
Deformities of skeletal structures, the heart, and other organs are a recurrent problem in species used in intensive aquaculture.
Elevated egg incubation temperature appears to be a high risk factor in the development of these malformations, but the causal
relation has not been established. Our aim was to identify candidate genes involved in the development of heat induced deformities
in Atlantic salmon (Salmo salar). Temperature sensitive genes were isolated by RNA Arbitrarily Primed (RAP)-PCR. A total of 33 RAP-PCR products were successfully
sequenced, and the expression of eight identified genes was further examined by RT-PCR from pooled samples of heat exposed
embryos. Five of these genes were demonstrated to be temperature sensitive, of which four were shown to be up-regulated and
one was down-regulated at elevated water temperatures. The atrial natriuretic peptide (ANP) gene, which is a promising candidate for heart deformities, showed the highest level of heat induction. Three additional
RAP-PCR products identified as heterogeneous nuclear ribonucleprotein (hnRNP) A0, acyl CoA binding protein (ACBP) and mitochondrial (mt)-HSP70 showed up-regulated mRNA expression in response to elevated water temperature. The single down-regulated gene was identified
as an Atlantic salmon (Salmo salar) homolog of the cysteine and tyrosine-rich 1 (CYYR1) gene. This study demonstrated that a temperature elevation of only 4 °C during the early stages of the organogenesis in
Atlantic salmon induce altered expression of a number of genes, which are candidates for the development of heat induced deformities. 相似文献
17.
为探讨养殖水体底栖鱼类肠道排泄物对铜绿微囊藻休眠体复苏的影响,将青鱼和鲇肠道排泄物与铜绿微囊藻休眠体用野外养殖水域沉积物(底泥)混匀包埋,在10、15和20°C梯度温度下进行休眠体复苏实验。结果显示,铜绿微囊藻休眠体主要复苏期为第3～15天,在10和15°C条件下,青鱼排泄物组(MP)、鲇排泄物组(SA)和青鱼-鲇排泄物混合组(MP-SA)铜绿微囊藻休眠体复苏率均显著高于对照组(CK),且MP组也显著高于SA组和MP-SA组;在20°C条件下,MP组铜绿微囊藻休眠体复苏率显著高于SA组、MP-SA混合组和CK组,但SA组和MP-SA组与CK组复苏率并无显著性差异。实验过程中MP组沉积物中优势菌群以假单胞菌为主,SA组和MP-SA组优势菌群分别以芽孢杆菌和厚壁菌为主,第0～12天为菌群增殖期,且此期间沉积物-水体界面(SWI)实验MP组、SA组和MP-SA组溶解氧含量(DO)和氮磷比(N/P)均显著低于对照组。研究表明,青鱼和鲇肠道排泄物能促进铜绿微囊藻休眠体复苏,且这种促复苏效果在低温区间(10～15°C)更显著,可能是排泄物中菌群在生长增殖期降低了沉积物-水体界面N/P和DO的结果。研究结果对养殖水体底泥清淤和春季铜绿微囊藻水华防控具有一定的理论意义。 相似文献
18.
Using mark-recapture methods, the movements of the fluvial form of masu salmon (Oncorhynchus masou masou) in a mountain stream on the island of Kyushu, Japan, were studied. Most (78%) of the masu salmon were recaptured in the
pool in which they had been originally caught and tagged. Of those that moved between pools, the proportion of individuals
that moved during the breeding period was not significantly higher than the proportion that moved during the non-breeding
period. However, during the breeding period, a higher proportion of larger salmon moved than did smaller fish. The proportion
of mobile large males during breeding period was higher than that for small males. Also, it was found that a few individuals
showed long-range movement in the autumn. As a long-term movement, 78 individual fish (65%) that were recaptured more than
three times showed high sedentary tendencies. Sixteen individual mobile fish (13%) moved and returned to the original pool.
Fluvial form of masu salmon in Kyushu show a high sedentary nature; however, large mature males seem to actively move in search
of female during breeding period. 相似文献
19.
利用RACE技术从日本沼虾肝胰腺中克隆了cytMnSOD和mtMnSOD基因cDNA全长序列。cytMnSOD基因cDNA全长1 233 bp,开放阅读框为858 bp,编码286个氨基酸,N端含有60个氨基酸残基组成的延伸区;mtMnSOD基因cDNA全长1 113 bp,开放阅读框为654 bp,编码218个氨基酸,N端含有20个氨基酸残基组成的信号肽;cytMnSOD和mtMnSOD预测蛋白分子量及等电点分别为31.33、24.05 ku和5.62、7.12。日本沼虾cytMnSOD推导的氨基酸序列与其mtMnSOD的相似性为40%,二者均含有MnSOD的特征肽段(DVWEHAYY)、4个Mn2+结合位点和2个N-糖基化位点。Real-time PCR结果表明,cytMnSOD和mtMnSOD在日本沼虾肝胰腺、肌肉、血细胞、大颚器官、卵巢和鳃等组织均有表达,其中肝胰腺表达量最高;肝胰腺cytMnSOD和mtMnSOD基因的表达量在蜕皮间期最高,蜕皮后期和蜕皮前期较低。嗜水气单胞菌刺激后3 h,肝胰腺cytMnSOD和mtMnSOD的表达量显著增加,推测MnSOD是参与机体免疫防御反应的一种重要分子。 相似文献
20.
为探究sox9基因在大黄鱼性别决定与分化过程中的作用,利用RACE方法克隆得到大黄鱼sox9a和sox9b 2个基因,采用实时荧光定量PCR (qRT-PCR)分析其在雌雄个体不同组织和不同发育阶段的表达规律,并检测了其在17β-雌二醇处理后的遗传雄性和17α-甲基睾酮诱导处理后遗传雌性幼鱼中的表达变化。结果显示,大黄鱼sox9a c DNA全长2 442 bp(NCBI登录号:MH996431),包含476 bp 5′UTR、466 bp 3′UTR、1 500 bp ORF,编码499个氨基酸。大黄鱼sox9b cDNA全长为2 199 bp (NCBI登录号:MH996432),包含335 bp5′UTR、415 bp 3′UTR、1 449 bp ORF,编码482个氨基酸。qRT-PCR分析显示,sox9a基因主要在性腺、眼、脑、肝脏中表达,精巢中的表达量显著高于卵巢;sox9b在大黄鱼各组织中广泛表达,但以精巢中表达量最高,而卵巢中只有痕量表达。在鱼苗性腺发育初期,sox9a/b的表达量都维持在较低水平;随着鱼苗长大,sox9a/b的表达量在84 dph、123 dph 2次达到高峰,随后开始下降,10 mph后又逐渐上升。17β-雌二醇处理能够显著下调遗传雄性大黄鱼sox9a和sox9b基因在性腺中的表达,17α-甲基睾酮处理则显著上调遗传雌性大黄鱼sox9a和sox9b基因在性腺中的表达。研究表明,sox9a/b基因与大黄鱼性别发育和分化过程密切相关,对大黄鱼精巢的发育与维持起重要的调控作用,而且两个基因的功能可能具有一定程度的分化。 相似文献