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1.
<正> 近几年,名优品种养殖迅猛发展,市场需求增加。尤其罗氏沼虾需求日趋增大。1998年,邯郸市水产技术推广站进行了鱼种池套养罗氏沼虾试验,收效甚佳。试验池面积0.67hm~2,养殖周期120d收获草、鲢鱼种2861kg(其中,草鱼种2142kg,鲢719kg),平均规格50g,罗氏沼虾525kg,平均规格38g,总产值达88720元,经济效益十分显著。现将试验情况介绍如下:  相似文献   

2.
为查明运动过程中罗氏沼虾的行为特征及其与肌肉能量代谢的关系,实验设置了对照、低、中、高4种不同强度的游泳和弹跳实验,研究了运动后罗氏沼虾的行为、能量来源和相关代谢酶活性。游泳强度通过在特定时间内设置不同的水流速度来确定,对照、低、中、高强度的水流速度分别为0 (自由运动)、5 (200 min)、10 (200 min)和15 cm/s (游泳至疲劳)。弹跳强度通过在特定时间内设置不同触碰频率来确定,对照、低、中、高强度的触碰频率分别为0 (自由运动)、0.033 (5 min)、0.050 (5 min)和0.067 Hz (弹跳至疲劳)。结果显示,罗氏沼虾各运动组游泳足和尾肢的最大摆动频率和最大摆动幅度均显著高于对照组。各运动强度组肌肉蛋白质含量与对照组之间无显著差异,肌肉糖原含量均显著小于对照组,低强度游泳组肌肉甘油三酯含量小于对照组。中、高强度游泳组游泳足肌肉乳酸脱氢酶(LDH)活性和乳酸含量显著高于对照组,低强度游泳组游泳足肌肉丙酮酸脱氢酶、苹果酸脱氢酶和脂肪酶活性显著高于对照组。无论弹跳强度高低,罗氏沼虾腹部肌肉LDH酶活性和乳酸含量均显著高于对照组。研究表明,罗氏沼虾通过...  相似文献   

3.
通过对常见甲壳类水产品中呋喃西林代谢物氨基脲本底含量的调查及来源分析,为水产品质量安全监管提供依据。本研究运用液相色谱-串联质谱法,对常见的4种甲壳类水产品中本底氨基脲的含量进行测定。结果表明,在4种甲壳类水产品中,日本沼虾和罗氏沼虾中氨基脲检出率达100%,日本沼虾中氨基脲平均检出值为6.92μg/kg,罗氏沼虾中氨基脲平均检出值为2.52μg/kg,均超过现行残留限量,而凡纳滨对虾和中华绒螯蟹中的氨基脲含量较低。本研究的结果为甲壳类水产品中氨基脲残留限量的制定提供了数据支持。  相似文献   

4.
为探究不同生长时期养殖日本沼虾(Macrobrachium nipponense)体内氨基脲(Semicarbazide,SEM)的存在特征与变化规律,从养殖池塘采集不同生长时期日本沼虾样品,对各组织中SEM含量进行测定。结果表明:不同生长阶段日本沼虾样品中均有SEM检出,肌肉、甲壳、附肢、眼柄、鳃、肝胰腺中总SEM含量分别为(6.88±0.15)17.11±0.62、(107.30±1.10)306.09±8.69、(243.90±8.55)532.31±26.27、(85.27±3.19)122.82±2.60、(48.43±2.13)85.60±1.33、(13.51±1.15)25.94±1.78μg/kg,呈现:附肢>甲壳>眼柄>鳃>肝胰腺>肌肉的含量分布特征。SEM在肌肉和肝胰腺中主要以游离态形式存在,游离态SEM所占平均比例分别为67.35%和72.4%,在甲壳、眼柄、附肢、头胸部和鳃中主要以结合态形式存在,结合态SEM所占平均比例分别为89.50%、87.16%、85.68%、80.48%和73.30%。随着养殖过程进行,肌肉中总SEM含量总体逐渐降低,甲壳和附肢中总SEM含量呈现总体上升的变化趋势。研究结果可为甲壳类水产品中SEM残留限量标准的修订和采样技术规范的制订提供基础数据。  相似文献   

5.
选取初始体重为(0.32±0.02) g的罗氏沼虾450尾,随机分为5组,每组设3个重复,每个重复30尾虾。以基础饲料为对照组,分别于基础饲料中添加10 mg/kg、20 mg/kg、40 mg/kg、400 mg/kg植物甾醇,饲养试验为期70天。试验结果表明:①与对照组相比,添加20 mg/kg、40 mg/kg和400 mk/kg植物甾醇组罗氏沼虾的终末体重、增重率和特定生长率显著高于对照组(P 0.05),添加40 mk/kg组的饲料系数显著低于对照组和添加10 mg/kg和400 mg/kg组(P 0.05),添加40 mk/kg组的肥满度显著高于对照组和添加10 mg/kg和400 mg/kg组(P 0.05)。②添加20 mg/kg和40 mg/kg植物甾醇其肝脏脂肪酶活性显著高于对照组(P 0.05),对肝脏蛋白酶和淀粉酶活性则没有显著影响(P 0.05)。③添加20 mg/kg、40 mg/kg和400 mg/kg植物甾醇组罗氏沼虾的含肉率显著高于对照组(P 0.05),添加40 mg/kg和400 mg/kg植物甾醇显著降低了滴水损失(P0.05)。④添加20 mg/kg、40 mg/kg和400 mg/kg植物甾醇显著提高了罗氏沼虾肌肉粗蛋白质含量(P 0.05),添加40 mg/kg和400 mg/kg植物甾醇显著提高了罗氏沼虾肌肉谷氨酸和甘氨酸含量(P 0.05)。在本试验条件下,在罗氏沼虾基础饲料中添加40 mg/kg植物甾醇可获得最佳生长性能和肌肉品质。  相似文献   

6.
利用稻田养殖罗氏沼虾，放养体长2．5cm的虾苗，经4个月养殖，平均规格达18．2g，亩产25．2kg，成活率40．72％。水稻亩产476．5kg。每亩纯收入1822元。试验表明，稻田养殖罗氏沼虾是增产增收的好途径。  相似文献   

7.
上海郊区养殖的罗氏沼虾出现了头部“白点病”,造成大量沼虾死亡。患病罗氏沼虾的明显临床症状是位于额角基部的造血组织呈白色不透明状。组织病理学检查表明,病虾造血组织细胞出现异常的嗜碱性包涵体。超微病理研究发现,其造血细胞的细胞质被大量病毒颗粒侵染,该病毒颗粒呈二十面体结构,直径大小为(153±8)nm。聚合酶链式反应(PCR)检测表明,该病毒三磷酸腺苷(ATP)酶基因与十足目虹彩病毒(DIV1)基因序列一致性达100%。根据综合病理和分子检测结果,确认此次上海地区养殖罗氏沼虾“白点病”是由十足目虹彩病毒(DIV1)导致的。文章可为罗氏沼虾“白点病”的诊断和病害防控提供理论依据。  相似文献   

8.
不同脂肪源对罗氏沼虾生长及体组织常见组分的影响   总被引：4，自引：0，他引：4  
用5种不同脂肪源组合的饲料(Ⅰ.鱼油0.5%+豆油2.5%;Ⅱ.鱼油0.5%+菜籽油2.5%;Ⅲ.鱼油0.5%+花生油2.5%;Ⅳ.鱼油0.5%+亚麻油2.5%;Ⅴ.豆油1.5%+亚麻油1.5%)投喂体重为(2.22±0.04)g的罗氏沼虾(Macrobrachium rosenbergii)40 d,研究不同脂肪源对其生长及全虾和肌肉中水分、粗蛋白、粗脂肪含量的影响。结果显示:在生长方面,第Ⅴ组的罗氏沼虾增重显著高于Ⅱ组和Ⅲ组(P<0.05),Ⅰ组和Ⅳ组增重也显著大于Ⅱ组(P<0.05)。在体成分方面,Ⅰ组全虾总水分含量最低,显著低于Ⅲ组和Ⅳ组(P<0.05),其他各组间无显著差异(P>0.05);Ⅴ组全虾粗脂肪含量最高,显著高于其他各试验组(P<0.05);Ⅲ组全虾粗蛋白含量显著低于Ⅰ组、Ⅱ组及Ⅴ组(P<0.05);Ⅳ组肌肉总水分含量显著高于其他各组;肌肉粗脂肪和粗蛋白含量各试验组之间差异不显著(P>0.05)。  相似文献   

9.
以0(对照)、50、100和150 mg/kg饲料的剂量将左旋咪唑(LMS)添加于基础饲料中制成颗粒饲料投喂罗氏沼虾(Macrobrachium rosenbergii)14 d,采样测定了罗氏沼虾血细胞吞噬活性、血清酚氧化酶(PO)、溶菌酶(LSZ)及超氧化物岐化酶(SOD)活性,并以6×105cells/mL浓度的致病性嗜水气单胞菌(Aerom onas hydrophila)对罗氏沼虾进行肌肉注射(20μL/尾),记录接种7 d后罗氏沼虾的累积死亡率。结果表明,3个LMS处理组的罗氏沼虾血细胞吞噬百分比和吞噬指数、血清PO、LSZ及SOD活性均显著地高于对照组(P<0.05);LMS处理组的罗氏沼虾对嗜水气单胞菌的抵抗力明显增强。因此,饲喂适量的LMS能促进罗氏沼虾的免疫力和抗病力;在本试验条件下,100 mg/kg饲料的剂量为最适添加剂量。  相似文献   

10.
盐度对罗氏沼虾能量代谢和运动能力的影响   总被引：2，自引：0，他引：2  
为研究盐度对罗氏沼虾(Macrobrachium rosenbergii)能量代谢和运动能力的影响, 设置了 0 (对照)、4、8 和 12 共 4 个盐度胁迫水平, 研究了罗氏沼虾在胁迫 48 h 后的耗氧率、鳃丝和肌肉能量代谢酶活性及其游泳和弹跳能力。结果显示, 耗氧率在盐度升至 4 时并无显著变化(P＞0.05), 但 8 和 12 盐度组的耗氧率显著高于对照组(P＜0.05)。 鳃丝己糖激酶(HK)、磷酸果糖激酶(PFK)和乳酸脱氢酶(LDH)活性在不同盐度条件下并无显著变化(P＞0.05), 但鳃丝丙酮酸脱氢酶(PDH)和细胞色素 C 氧化酶(COX)活性在盐度为 8 时显著升高(P＜0.05), 并且鳃丝 PDH 和 COX 活性均与耗氧率呈显著线性正相关(P＜0.05)。盐度在 8 时罗氏沼虾的游泳足肌肉和腹部肌肉 HK、PFK 和 LDH 活性并无显著变化(P＞0.05), 但游泳足肌肉和腹部肌肉 PDH 和 COX 活性显著下降(P＜0.05); 盐度升至 12 时游泳足肌肉和腹部肌肉 HK、PFK、LDH、PDH 和 COX 活性均显著下降(P＜0.05)。运动能力结果显示, 盐度升至 8 时游泳能力显著下降(P＜0.05), 盐度升至 12 时弹跳能力显著下降(P＜0.05)。游泳能力与游泳足肌肉 PDH 和 COX 活性呈显著线性正相关(P＜0.05); 弹跳能力与腹部肌肉 HK、PFK 和 LDH 活性呈显著线性正相关(P＜0.05)。研究表明, 罗氏沼虾通过增加氧气摄取用于鳃丝有氧代谢以应对盐度胁迫, 但这些生理调节导致肌肉能量代谢酶活性下降, 造成罗氏沼虾的游泳和弹跳能力减弱。  相似文献   

11.
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12.
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   

13.
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   

14.
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15.
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   

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   

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