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1.
Abstract The conflict between the cormorant, Phalacrocorax carbo sinensis Shaw, and commercial and recreational fisheries was investigated in the foraging area of a cormorant colony of 5000 breeding pairs in Horsens Fjord, Denmark. Depredation of commercial pound nets was studied by stocking a large net pen with hatchery-reared rainbow trout, Oncorhynchus mykiss (Walbaum). When avian predation was precluded with a cover net, background mortality was around 15% day-1. When the cover net was removed, mortality increased to 98% day-1. Direct observation revealed that a flock of cormorants emptied the pound net in about 30 min, consuming 110 fish weighing a total of approximately 50 kg. The cormorants were able to catch trout weighing more than 1 kg, i.e. almost 50% of their own body weight. The impact of the cormorant colony on recreational fishing in the area was studied by stocking Carlin-tagged sea trout, Salmo trutta L., smolts into the two rivers that drain into the fjord. The cormorant colony lies between the river outlets and the open sea. Tag recovery from a 3-year programme was only about 2%, compared with about 10% for smolts stocked in areas of low cormorant density.  相似文献   

2.
《水生生物资源》1999,12(1):1-10
We propose a simple method to quantify the morphology of 2–3-year-old carps (Cyprinus carpio) which is related to their fillet yield. This method is based on the automated image analysis of the lateral projection of the fish (mask). Seven morphological measurements specifically related to fillet yield of carps were defined. The comparison between this method and the conventional quantification offish shape, based on measurements of skeletal landmarks, increases the significance of this fitting. From the analysis of the morphometric data, we propose a profitable carp morphotype which is defined by four angles and two distances which quantify the shape of the head and the position of the caudal peduncle, respectively. The main characteristic of this morphotype is the absence of a large dorsal development, and the ventral position of the caudal peduncle.  相似文献   

3.
4.
Seasonal changes in the immune activities of common carp (Cyprinus carpio)   总被引:1,自引:1,他引:1  
Various endocrinological and immunological parameters involved with the seasonal changes of immunocompetence in common carp, Cyprinus carpio reared under natural conditions were investigated. Plasma concentrations of steroid hormones, IgM levels, IgM-secreting cell (IgMSC) numbers, and water temperature were considered as major parameters. Testosterone, 11-ketotestosterone in males and estradiol-17β in females detected by RIA, increased simultaneously with gonadal maturation, but no significant correlation was found with IgM production measured by ELISA. IgM levels were very high during the spawning season, but did not fluctuate much during the other seasons even at high water temperatures. These changes of IgM are certainly related to sexual maturation. In addition, IgMSC numbers were also high during the spawning season. This positive interaction between endocrine and immune parameters could contribute to the immune systems of common carp being more effective during spawning season. Interestingly, cortisol levels increased with the water temperature and were high during the spawning season, but had no suppressive effect on the IgM levels and IgMSC numbers.  相似文献   

5.
Abstract. Counts were made of cormorants, Phalacrocorax carbo (L.), feeding on the River Bush. County Antrim. Northern Ireland during the post-dawn period on three occasions. Two of the counts during May 1986 indicated that up to 264 birds may have been feeding at least once per day throughout the catchment during the salmon, Salmo salar L., smolt run. The number of feeding birds had dropped to an estimated 61 by the time of the third count on 1 July 1986. Stomach samples from shot birds showed that upstream feeding was concentrated on wild smolts and brown trout. Salmo trutta L. However, cormorant predalion downstream from the salmon hatchery at Bushmills was restricted solely to hatchery smolts. Estimates of the total daily predation rates were calculated at 653–1214 wild smolts. 107–231 hatchery smolts and 422–785 brown trout. The possible impact of this level of predation on the salmonid stocks of the river was assessed.  相似文献   

6.
In addition to direct predation, cormorants can affect carp pond fish stock through disturbance and wounding of the fish. Fish stress response was evaluated by catch per unit effort (CPUE) using lift‐net sampling. A significantly higher (P<0.001) CPUE was recorded in the littoral region of ponds affected by cormorant visits (43.6 ± 39.6) in comparison with a control pond (CP) without their occurrence (0.9 ± 1.1). Stress indices, spleen somatic index (SSI) and Fulton's condition coefficient (FCC) were evaluated for fish subject to two stress factors, hunting cormorants (HC) and pond harvesting (PH), and compared with levels in fish from the CP. Both SSI and FCC decreased significantly (P<0.05) in PH and HC fish in comparison with the control group, while non‐significant differences were observed in both SSI and FCC indices among the HC and PH groups. Plasma biochemical indices (cortisol, glucose and lactate concentrations) were significantly higher (P<0.01) in the PH group as compared with the HC and CP groups. Concentrations in the HC and CP groups did not differ significantly. Total plasma protein levels were significantly higher (P<0.01) in HC fish compared with CP fish, but did not differ significantly from PH fish.  相似文献   

7.
二、三倍体乌克兰鳞鲤染色体核型分析   总被引:2,自引:0,他引:2  
以二、三倍体乌克兰鳞鲤为材料,采用植物血球凝集素(PHA)体内注射,肾组织细胞短期培养,常规空气干燥法制备染色体.其核型分析结果:二倍体乌克兰鳞鲤染色体2n=100核型公式为:26m+30sm+30st+14t,染色体臂数NF=156;三倍体乌克兰鳞鲤染色体的核型公式为3n=150=39m+45sm+45st+21t,染色体臂数NF=234,二、三倍体染色体数之比为1:1.5.二倍体核型与已报道的鲤鱼染色体核型相似.未发现性染色体.  相似文献   

8.
去除内脏对冰藏鲤感官、化学和微生物变化的影响   总被引:1,自引:0,他引:1  
以感官、TVBN、菌落总数、假单胞菌为指标,探讨去除内脏对冰藏鲤(Cyprinus carpio)品质变化及货架期的影响。结果表明,去除内脏和未去除内脏冰藏鲤的高品质期分别为333h和330h,货架期分别为575h和654h;去除内脏鲤冰藏的货架期略短,但无显著性差异(P0.05)。在冰藏过程中二者假单胞菌数量占优势,高品质期终点,去除内脏和未去除内脏鲤的菌落总数(CFU/g)的对数值分别为6.33±0.02和6.07±0.03;假单胞菌数(CFU/g)的对数值分别为6.15±0.19和6.04±0.01;挥发性盐基氮值分别为(10.86±0.50)mg/(100g)和(10.15±0.01)mg/(100g)。货架期终点,二者细菌总数(CFU/g)的对数值分别为7.06±0.18和6.90±0.14;假单胞菌数(CFU/g)分别为6.89±0.13和6.31±0.05;挥发性盐基氮值分别为(19.03±0.90)mg/(100g)、(21.15±0.80)mg/(100g)。二者在高品质期终点和货架期终点的各指标均无显著性差异(P0.05)。与未去除内脏鲤相比,冰藏初期去除内脏鲤的挥发性盐基氮值略低,而其细菌增殖较快且直接进入对数增长期,这可能是由于去除内脏过程对鱼体造成破坏所致,而过了高品质期后,无论是挥发性盐基氮值还是感官评分都比未去除内脏的高,因此去除内脏鲤的货架期略短。  相似文献   

9.
鲤病毒病原的感染性测定   总被引:5,自引:1,他引:5       下载免费PDF全文
为查明养殖鲤(Cyprinus carpio)突然大批发病死亡的原因,对鲤病样品进行了细胞攻毒、空斑测定、电镜观察,以及鱼体感染等实验。先以患病鲤的组织匀浆液,经过滤后,分别接种到草鱼鳍条细胞(GCF)、鲤上皮瘤细胞(EPC)等14种培养细胞中。利用倒置显微镜观察显示,在1-2d内,该病鱼组织匀浆液可使其中9种细胞出现典型的细胞病变。收集出现病变的细胞液(即病毒悬液),进一步进行病毒滴度检测、空斑测定和鱼体感染实验。结果显示,在GCF细胞上的病毒滴度为10^7.3TCID50/mL;在FHM,TSB和GCO等细胞中可产生直径1~4mm的圆形空斑,空斑的大小与宿主细胞的种类和接种的病毒浓度有关。通过对感染细胞制备的超薄切片和病毒负染样品进行电镜观察,显示这是一类呈典型子弹头样的弹状病毒颗粒。感染了病毒悬液的鲫和鲤先后在第2天和第3天开始出现病症,间隔1~2d后发病的鱼开始死亡,至第14天,两种感染鱼的死亡率均达到83.3%。收集人工感染后濒死的鲫和鲤,分别制备组织匀浆液,回接感染鱼类培养细胞,24h内能使其出现与原发病鲤组织匀浆液所引起的类似的细胞病变。因此证实患病鲤是由病毒病原感染所致。[中国水产科学,2006,13(4):617—623]  相似文献   

10.
Fish that have escaped from a cormorant’s (Phalacrocorax carbo sinensis (L.)) grasp and/or which could not be swallowed due to their size suffer from various injuries resulting in consecutive infections and subsequent increased mortality. Computer-assisted image analysis was applied to describe the extent of such injuries. Two-year-old mirror carp, Cyprinus carpio L. (TL 200–300 mm, W 200–300 g) showed injuries ranging over approximately 10% of the total body surface. Immediately after wounding, the damaged epithelium (scars) cover 5–35%, and deeper subdermal wounds caused by the beak tip pervading into muscle tissue cover an area of 1–2% of the total body surface. On the side impacted by the cormorant’s lower mandible, extensive areas of epidermal contusions (scars) occur. As time progresses, these ratios change—deeper necroses represent up to 10% of the total body surface and healing epithelial scars comprise just 1–2%. In wounded silver carp, Hypophthalmichthys molitrix Val. (300–400 mm, W 500–700 g), the share of subdermal wounds usually does not exceed 0.5% due to their compact scaly cover. During pond draining due to fish harvesting, the size spectrum of wounded fish increases and may also often include bigger fish (e.g., European catfish, Silurus glanis L.) up to 2.2 kg.  相似文献   

11.
《水生生物资源》2003,16(5):399-407
The common carp is one of the main aquaculture species in the world. Despite this, most of the production is carried out using unselected strains. Selective breeding for fast growth has not proven to be effective in this species, but other traits (disease resistance, shape) could be successfully selected for. Most heritability estimates in the literature are unreliable due to environmental biases, but complementary results from population genetics and comparison of strains seem to indicate that there should be a potential for selective breeding in this species, including selection for growth rate, provided the base populations are variable enough (e.g. synthetic strains). New techniques such as parentage assignment with microsatellites and use of doubled haploid progenies may help describe much more accurately, without environmental bias, the genetic determination of traits of interest in the carp. This could be a new opportunity to design efficient breeding programs in this important species.  相似文献   

12.
应用荧光DDRT-PCR从鲤外周血白细胞克隆了鲤胸腺素β(thymosinβ,Tβ)基因cDNA全序列。序列分析表明,TβcDNA全长528bp,其完整的读码框架位于40~178bp,编码46个氨基酸,5'非编码区长39bp,3'非编码区长为348bp,且具有Poly(A)加尾信号(AATAAA),将该基因序列递呈GenBank,注册序列号为AY457946。氨基酸序列同源性分析显示,鲤Tβ氨基酸序列与鲤Tβa、斑马鱼Tβa及斑马鱼Tβ-2同源性均为84%。在系统发生树上,鲤Tβ与鲤、斑马鱼、白斑狗鱼和鲑Tβa及斑马鱼Tβ2聚类。  相似文献   

13.
ABSTRACT: Nucleoplasmin, first isolated from Xenopus laevis eggs, promotes nucleosome assembly. Hereby, we have purified a nucleoplasmin-like protein from carp ( Cyprinus carpio ) eggs using ion exchange and subsequent gel filtration columns. The protein was recognized by a polyclonal antiserum against Xenopus laevis nucleoplasmin and had an amino acid composition similar to other member of the nucleoplasmin family proteins. Partial amino acid sequences from the cyanogen bromide (CNBr)-cleaved fragments showed high homology with Xenopus nucleoplasmin. The protein was also found to form an oligomeric complex and to be phosphorylated. Moreover, this protein promoted sperm nuclear decondensation as well as that of nucleoplasmin from Xenopus laevis eggs. These results suggest that the fish protein isolated here is a member of nucleoplasmin family.  相似文献   

14.
Isolated carp hepatocytes cultured in serum-free, chemically defined medium were used to investigate within the same cell preparation characteristics of the binding of insulin as well as effects of insulin on cellular metabolism. The binding of human [125I]-insulin to carp hepatocytes was studied in kinetic, saturation and displacement experiments. A dependency of insulin binding on the collagenase used for cell isolation was demonstrated. Insulin binding decreased during the first 12h of culture but remained constant during the following 12h. The kinetic experiments revealed that [125I]-insulin binding reached a steady state within 20–30 min of incubation. The mathematical analysis of the saturation experiments demonstrated the existence of two populations of binding sites, one with high affinity (Kd1 = 5.5 pM) and low capacity (Bmax1 = 0.14 fmol/mg protein or 77 binding sites/cell) and one with low affinity (Kd2 = 2.4 nM) and high capacity (Bmax2 = 17.6 fmol/mg protein or 9623 binding sites/cell). In competition experiments, 312 pM [125I]-insulin was displaced by cold insulin, IGF-I and IGF-II with IC50 values of 2.2, 7.9 and 20.3 nM, respectively. Glucagon was without effect. Binding of insulin to carp hepatocytes resulted in a significant reduction of glucose release and a significant increase of protein synthesis as of de novo fatty acid synthesis. dedicated to Prof. Dr. W. Hanke on the occasion of his 65th birthday.  相似文献   

15.
16.
鲤脑组织cDNA文库的构建及脑室管膜素基因鉴定   总被引:1,自引:0,他引:1  
用Gubler-Hoffman法构建了低温下鲤(Cyprinus carpio Linnaeus)脑组织cDNA文库,经测定库容量为5.7×105 CFU/mL,文库的重组率接近95%,平均插入片段长度约为1.5 kb,符合文库保存和筛选实验的要求.同时,根据鲤与低温相关消减cDNA文库中低温下特异表达基因片段序列,设计PCR引物在此cDNA文库中进行PCR检测和序列测定,使用BLAST软件将测序的10个cDNA序列同GenBank等数据库进行比对,结果显示8个阳性克隆有相关同源性,2个克隆为功能未知的基因,全长率近75%;以上结果说明本实验所构建的cDNA文库质量较高,可作为筛选与鲤低温性状相关的功能基因的重要资源.同时对其中一个与低温相关的基因脑室管膜素基因构建了表达载体,为进一步验证该基因在鱼类低温适应中所发挥的作用及其作用机理奠定了基础.  相似文献   

17.
赵紫霞  张研  曹顶臣  孙昭宁  许建  徐鹏 《水产学报》2017,41(12):1829-1837
为发掘适用于基因工程抗病育种的鱼类启动子,通过实时荧光定量PCR实验对鲤Rab GTP酶(Ras-associated binding-GTPases 1a3,Rab1a3)基因的表达模式进行了分析,证实该基因在鳃、头肾等与机体免疫防御功能密切相关的组织内转录水平较高,且免疫激活后转录显著增强,符合基因工程抗病育种所需的外源免疫基因转录模式。从鲤细菌人工染色体文库中,使用Rab1a3基因特异引物筛选获得包含该基因区域的文库克隆,测序获得该基因完整序列,以及上下游调控序列。通过生物信息学手段,预测到长度为1014 bp的鲤Rab1a3基因启动子序列,该启动子不具有典型的TATA盒或CpG岛特征,存在多个免疫相关转录因子结合位点。在草鱼肾组织细胞系内验证该启动子活性,结果显示,绿色荧光蛋白基因和萤火虫荧光素酶基因都能够在该启动子驱动下表达,证实该片段具有启动子活性,且启动子活性在受到免疫诱导后增强,双荧光素酶报告基因检测结果显示,该启动子活性在免疫刺激后增强至免疫刺激前的8.67倍。研究表明,鲤Rab1a3基因启动子有望被开发成为免疫诱导型的基因工程元件,驱动外源免疫基因在鱼体内适时表达,抵御外界病原感染,同时避免非必要条件下的过度表达形成生长负担。  相似文献   

18.
洛美沙星在鲤鱼体内的药物动力学及残留   总被引:3,自引:0,他引:3  
用高效液相色谱 (HPLC)测定方法研究洛美沙星在鲤鱼 (Cyprinuscarpio)体内的药物动力学和残留。洛美沙星以 2 0mg/kg体重单剂量口灌鲤鱼后 ,测定其血浆药物浓度 ,最低检测限为 0 0 5 μg/mL ,动力学模型符合开放性有吸收二室模型 ,药物动力学参数 :表观分布容积 (Vd/F)、吸收半衰期 (tl/ 2kα)、分布半衰期 (t1/ 2α)以及消除半衰期 (t1/ 2 β)分别为 5 2 1L/kg、 0 31h、 1 0 2h、 2 0 0 3h ,其药时曲线下面积(AUC)为 110 92 μg·h/mL。以相同剂量单次口灌鲤鱼后 ,在不同的天数测定了鲤鱼皮肤、肌肉和肝胰脏中洛美沙星的残留 ,在给药 12天后 ,洛美沙星在各组织中均能检测到且残留均低于 0 0 8μg/g ,结果表明洛美沙星在鲤鱼体内消除缓慢、残留期较长 ,休药期不低于 12天。  相似文献   

19.
报道了孟家段水库饵料动物资源状况,并据此推算了以动物为主要食物的鳙鱼、鲤鱼、鲫鱼的鱼产力。指出该水库平均鱼产力;鳙鱼为82kg/hm~2,鲤鲫鱼为10.7kg/hm~2。  相似文献   

20.
在鲤(Cyprinus carpio)感染鲤疱疹病毒Ⅲ型(CyHV-3)不同时期,通过分析鲤疱疹病毒标志基因TK和ORF72与自噬标志基因Beclin-1、LC3、P62的差异表达情况,探讨在CyHV-3感染中自噬的发生情况。研究表明:(1)抗病选育组与未选育组鲤TK和ORF72基因以及自噬标志因子Beclin-1、LC3、P62基因相对表达量均呈现先升高后降低的趋势; TK和ORF72基因相对表达量选育组均极显著低于未选育组(P<0.01)且在感染144 h达到最高;(2)选育组鲤Beclin-1、LC3、P62基因相对表达量在感染48h达到最高,且Beclin-1、LC3基因表达量极显著高于未选育组(P<0.001),P62显著高于未选育组(P<0.05);(3)未选育组鲤Beclin-1、LC3、P62基因相对表达量在感染96h达到最高且极显著高于选育组(P<0.001),而P62基因相对表达量持续在感染144h、192h极显著高于选育组(P<0.01),说明P62基因表达发生了聚集;(4) LC3蛋白表达趋势与基因相对表达量趋势一致。以上结果表明C...  相似文献   

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