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1.
采用19对大口鲇(Silurus meriaionalis)微卫星引物对兰州鲇(Silurus lanzhouensis)野生和人工繁育2个不同群体进行微卫星标记的遗传结构分析,结果显示:(1)2个不同种群检测出11个有效微卫星位点,共94个等位基因;各基因座位间除DQ223153与DQ223150,DQ223177与DQ223182,DQ223164与DQ223176存在一定程度连锁(P<0.05),其余连锁关系不显著。(2)2个种群平均有效等位基因数为7.28,平均观测杂合度为0.8873,平均期望杂合度为0.7732,PIC值0.7055,均为高度多态,但人工繁育群体的总扩增位点数和遗传多样性均低于野生群体;(3)两群体间的遗传相似性指数(I)为0.9915,遗传距离(D)为0.0086;各位点F-统计量分析结果表明,群体遗传分化系数(FST)为-0.0392~0.0754,平均值为0.0205;基因流(Nm)为1.6625。综合结果说明,虽然兰州鲇人工繁育群体的遗传多样性降低,但两群体遗传多样性丰富,亲缘关系较近,遗传分化较低,属于同一个种内水平遗传变异。  相似文献   

2.
利用10个微卫星标记,对2代群体选育的建鲤(Cyprinus carpio var.Jian)和封闭水体的广西野生鲤鱼进行遗传多样性分析,共检测到53个等位基因,等位基因位点数在4~7个之间,平均等位基因数5.3个,片段长度在118~284 bp之间,有效等位基因在1.167 5~1.520 3,平均为1.360 2,广西野生鲤群体的有效等位基因数1.562,大于建鲤的1.388;位点观测杂合度在0.397~0.762之间,平均为0.562 6,期望杂合度0.301~0.629之间,平均0.463 3,广西野生鲤群体的期望杂合度0.581,大于建鲤的0.473;微卫星位点多态性信息含量(PIC)在0.289 7~0.685 0之间,平均多态信息含量0.438 8,为中度多态性,广西野生鲤群体多态信息含量0.685,大于建鲤的0.424,两个群体平均基因分化系数为0.106 9,广西本地野生鲤与建鲤的遗传距离为0.1463,相似性系数为0.828 4,表明广西野生鲤与建鲤之间存在明显的遗传异质性。  相似文献   

3.
采用垂直聚丙烯酰胺凝胶电泳技术对西施舌(Coelomactra antiquata)闭壳肌、鳃、外套膜、消化腺和足肌5种组织的18种同工酶进行组织特异性分析,并对其中11种同工酶进行了多态性的筛选。结果表明,西施舌同工酶的表达具有明显的组织特异性。消化腺与肌肉组织中的11种酶(ADH、AK、DIA、EST、GPI、IDH、MDH、PGM、SDH、SOD和XDH)可以得到稳定而清晰的酶谱。在11种酶的17个基因位点中有6个位点(aDH、EST-1、MDH-1、PGM,SOD.J和XDI-1)为多态位点,多态位点比例为35.3%。平均观测杂合度(风)和预期杂合度(见)分别为0.360和0.519,平均等位基因数目(M)为4.40。  相似文献   

4.
采用聚丙烯酰胺不连续凝胶垂直电泳技术对黄、渤海沿岸4个野生菲律宾蛤仔群体的同工酶进行了检测,8种同工酶共记录了18个基因座位,其中Est-1、Est-2、Sod-1、Sod-2、Ldh-1和Ldh-2共6个位点是多态的,多态座位百分数为33.33%。测得4群体平均等位基因数目为1.4412,平均有效等位基因数目1.1260,平均实际杂合度0.0570,平均期望杂合度0.0825,Hardy-Weinberg遗传偏离指数-0.2358,表明菲律宾蛤仔4个野生群体的遗传多样性属偏低水平。  相似文献   

5.
美国金鳟的同工酶分析   总被引:2,自引:1,他引:2  
本实验运用聚丙烯酰胺凝胶电泳法对养殖型美国金鳟眼(E)、心(H)、肾(K)、肝(L)、肌肉(M)五种组织的乙醇脱氢酶(ADH)、酯酶(EST)、葡萄糖-6-磷酸脱氢酶(G-6- PDH)、谷氨酸脱氢酶(GDH)、乳酸脱氢酶(LDH)、苹果酸脱氢酶(MDH)和过氧化物酶(POD)等7种同工酶进行电泳研究。结果显示:美国金鳟中ADH、EST、G-6-PDH、GDH、LDH、MDH、POD、SOD 7种同工酶都有不同程度的组织特异性;美国金鳟群体同工酶分析共记录18个基因座位,其中有8个基因座位为多态,等位基因总数为26个,从而得出多态座位百分数P为44.44%,位点有效等位基因数Ne=1.4444,表明美国金鳟群体遗传多样性偏高。  相似文献   

6.
企鹅珍珠贝同工酶酶谱特征及其遗传分析   总被引:8,自引:1,他引:8  
余祥勇 《水产学报》2004,28(4):375-383
采用垂直板状聚丙烯酰胺梯度凝胶电泳分离技术,对企鹅珍珠贝闭壳肌、外套膜、鳃、消化盲囊、足组织的SOD、EST、LDH、G6PDH、MDH、ME 6种同工酶酶谱特征及其遗传控制进行了研究。6种同工酶在不同组织中的表达有明显的差异,同工酶分析共检测到18个位点,其中有16个位点具多态性,群体中,多态位点比例为88.8%,平均杂合度为0.396±0.029。有13个多态位点上的基因型频率与Hardy-Weinberg定律相符(P>0.05),位点Ldh-1、Ldh-2、Sod-2极显著偏离该平衡(P<0.01)。在G6pdh-1位点发现较高频率的无效等位基因。  相似文献   

7.
红鳍东方纯养殖群体生化遗传变异初步研究   总被引:2,自引:0,他引:2  
采用水平凝胶电泳技术对红鳍东方纯养殖群体进行了同工酶分析.本实验采用肌肉和肝脏两种组织,分析了8种酶,检测到9个位点,在0.99水平上,PGM*和IDHP*表现为多态,MPI*、LDH*、AAT*、SOD*、MDH-1*、MDH-2*和G3PDH*均为单态,多态位点比例为0.222 2,平均预期杂合度为0.099 8,实际观测杂合度为0.046 7,平均有效等位基因数目为1.184 0,PGM*位点的遗传偏离指数为-0.070 7,杂合子缺失,IDHP*位点无杂合子,遗传偏离指数为-1.  相似文献   

8.
利用在生长激素(GH)、生长激素释放激素(GHRH)和垂体腺苷酸环化酶激活多肽(PACAP)基因中发现的7个微卫星位点,分析了半滑舌鳎两个野生群体(渤海群体和黄海群体)和1个养殖群体间以及各群体内雌雄个体间的遗传多态性差异。结果表明,7个位点中有4个位点表现出多态性,在3个群体中的等位基因数的分布范围为2~37,平均为9.5;有效等位基因数分布范围为2~28.9,平均为8.4。各位点的平均观测杂合度、平均期望杂合度和平均多态信息含量分布范围分别为0.5145~0.7738、0.5690~0.8671和0.4829~0.8314。群体间的成对FST值及个体分配分析的结果表明,半滑舌鳎野生群体和养殖群体之间存在显著性遗传差异,而在两个野生群体之间差异不显著。此外,等位基因分布和双倍体基因型分布的差异性检测结果表明,这4个多态性位点在3个群体的雌、雄性别间均不存在显著性差异。  相似文献   

9.
选用实验室克隆的23个圆口铜鱼(Coreius guichenoti Sauvageet Dabry)微卫星标记分析了长江宜宾江段的圆口铜鱼群体遗传多样性,统计分析了有效等位基因数、观测杂合度Ho、期望杂合度He、多态信息含量(PIC)等遗传学指标。结果表明:23个位点有14个微卫星位点呈单态,9个位点出现多态,在这9个位点中共检测到48个等位基因,其平均有效等位基因数为5.3,多态信息含量在0.440~0.839之间变动,平均为0.670,除YT17和YT22位点属于中度多态外,其余7个位点均属于高度多态。平均观测杂合度为0.753,平均期望杂合度为0.728,表明该群体的遗传多样性较为丰富。  相似文献   

10.
采用聚丙烯酰胺凝胶垂直板电泳法对蓝色鳞鲤(Cyprinus carpio blue var)进行同工酶分析。结果表明:在蓝色鳞鲤的眼睛、肌肉、肝脏、心脏、肾脏5种组织中,14种酶(LDH、ADH、GDH、MDH、G-6-PDH、EST、POD、SDH、FDH、SOD、α-AMY、CAT、COX、ME)的同工酶谱均存在明显的组织特异性。14种酶共记录出33个基因位点,其中α-Amy-2、Cox-2、Est-1、Ldh-1、Mdh-1、Mdh-2和Sod-1为多态位点。蓝色鳞鲤群体的多态位点百分数为21.21%(P0.99),平均预期杂合度和平均实际杂合度分别为0.1079和0.2121,遗传偏离指数(d)值为正。平均有效等位基因数(Ne)为1.24。实验表明,目前蓝色鳞鲤群体的种质资源状况尚好,表现出明显的杂交优势。  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.
13.
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   

14.
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   

15.
16.
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   

17.
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   

18.
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   

19.
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   

20.
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