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1.
为评估池塘养殖日本鳗鲡(Anguilla japonica)对水质的影响,2007年12月～2009年2月对福建省南部某日本鳗鲡养殖场的6口池塘主要水质因子进行周年调查。结果表明,水温变化在20.73～31.97℃,季节性变化小,适宜日本鳗鲡生长的时间长;水体透明度较低,一般在15～30cm,浮游植物数量及抑藻剂的使用对透明度影响较大;溶解氧、pH值等全年均符合渔业水质标准;氨氮是主要的无机氮形式,全年最高值出现在夏季,其含量变化与水温变化趋势一致;亚硝酸氮含量大部分季节较低(<0.06mg/L);硝酸盐含量全年最高不超过0.2mg/L,其含量变化与叶绿素a含量变化规律基本一致;活性磷浓度仅冬季较低,其他季节均较高,可能是池塘中藻类常年旺盛生长的原因;高锰酸钾指数较高且季节变化不明显。控制养殖密度及合理使用水质处理剂对于池塘水质保证十分重要。 相似文献
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通过对黄颡鱼养殖池塘水体主要水质因子周年变化的测定与比较,探讨黄颡鱼养殖对水体环境的影响。研究主要测定了水体总磷(TP)、磷酸盐(PO4-P)、硝酸盐氮(NO3-N)、亚硝酸盐氮(NO2-N)和氨氮(NH4-N)含量。结果表明:养殖水体TP全年变化范围为0.08~1.17mg/L,5月份TP含量最低。PO4-P全年变化范围为0.02~0.27mg/L,10-12月份PO4-P含量较高为0.24~0.27mg/L。NO3-N全年变化范围为0.02~11.67mg/L,8月和11月份形成2个峰值;NO2-N全年变化范围为0.02~0.48mg/L,10月份呈现最高值0.48±0.01mg/L。NH4-N全年变化范围为0.06~2.02mg/L,5月份呈现峰值。溶解态无机氮(DIN)全年含量为0.43~11.76mg/L,且从全年氮平均含量进行考察,NO3-N、NH4-N和NO2-N分别占DIN的78.16%、16.72%和5.12%,N/P比值在5月和11月份出现2个峰值。黄颡鱼养殖池塘的水体氮和磷营养含量受光照、水温和鱼体活动等因素影响。 相似文献
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调查了两口海参养殖池塘的水质变化情况,对水温进行了全年监测,在4-9月份对pH、NH4+-N、NO2--N、TN、TP和COD进行定期监测。结果表明:池塘底层水温全年在-0.8~30.9℃之间变化,最低温出现在1月份,温度为-0.8℃,最高温出现在7月末,温度为30.9℃。pH在8.13~8.57之间变化,波动较小,池塘间差异不明显(P0.05);NH4+-N在0.090~0.309 mg/L之间变化,NO2--N变化范围为0.017~0.049mg/L,两池塘差异显著(P0.05);TN变化范围为2.749~5.880mg/L,TP为0.049~0.129mg/L,两池塘间差异不显著(P0.05);COD变化范围为7.28~8.40mg/L,非常稳定,池塘间差异不显著(P0.05)。监测期间水温有明显的季节变化,其他水质指标有波动,但没有明显的季节变化,水质整体保持在比较适宜的范围,海参生长良好。 相似文献
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南美白对虾池塘温室二茬养殖水质动态对比 总被引：1，自引：0，他引：1
通过监测两茬南美白对虾池塘温室的水质指标,研究了两茬养虾水质变化进程和动态对比。监测结果显示,第一茬养殖水体的水温在25.00~29.95℃,盐度在1.30~18.50,pH在8.30~10.98,溶氧量在7.34~16.09 mg/L,COD在6.63~16.73 mg/L,氨氮在0.32~4.07 mg/L,亚硝酸盐氮在0.01~0.78 mg/L,硝酸盐氮在0.05~1.87 mg/L,悬浮物在0.0047~0.393 8 mg/L;第二茬养殖水体的水温在24.70~31.80℃,盐度在1.15~16.25,pH在7.89~9.06,溶氧量在5.68~11.06 mg/L,COD在6.28~21.55 mg/L,氨氮在0.16~0.76 mg/L,亚硝酸盐氮在0.00~0.96 mg/L,硝酸盐氮在0.07~2.11 mg/L,悬浮物在0.0105~0.1984 mg/L。研究表明,池塘温室南美白对虾养殖水体的水质条件能满足南美白对虾生长的需求,同时第二茬养殖水质条件较第一茬差,建议在养殖过程中保持较高的溶氧量以降低氨氮和亚硝酸盐氮的含量,同时及时开展轮捕,降低池塘的承载量,可降低对虾病毒病暴发的风险。 相似文献
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《中国渔业质量与标准》2016,(4)
为摸清河南中牟县万滩镇地区养殖水体区域性问题,降低养殖风险,于2014年3—11月对实验池塘18项水质指标进行跟踪,并利用变异系数法进行分析、评价,从而为池塘水质评价和水质过程管理提供科学量化的依据。结果表明,亚硝酸盐氮、氨氮、硝酸盐氮、透明度、活性磷、浊度、溶氧、氧化还原电位等8项指标权重之和达到了80%,综合考虑监测指标间的关联关系和实际情况,最终确定以亚硝酸盐氮、氨氮、硝酸盐氮、透明度、活性磷、溶氧、温度、p H等8项指标为池塘日常管理监控因子。该地区主要指标变化范围为:氨氮0~1.0 mg/L,亚硝酸盐氮0~0.5 mg/L,硝酸盐氮0~3.5 mg/L,透明度10~40cm,活性磷0.1~0.8 mg/L,溶解氧3~9mg/L,水温16.9~29.2℃和p H7.22~8.85。该地区池塘在养殖前期出现高p H的现象,是各项因素叠加的综合结果;养殖中后期应重点关注水体的脱氮处理,预防长期高浓度氨氮、亚硝酸盐氮等毒性指标累积带来的风险。本研究为开展针对性的池塘水质调节和养殖过程管理提供参考依据。 相似文献
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刺参养殖池塘主要生态因子周年变化特征 总被引：1，自引：0，他引：1
《渔业现代化》2015,(5)
研究了刺参养殖池塘主要生态因子周年变化规律及养殖关键期重要生态因子的时空变化特点,以期明确参池基础生态学特征,为刺参养殖生产和管理提供科学支持。通过相应的国家标准和规范方法对养殖池塘水温、盐度、p H、溶氧量、透明度、氨氮浓度和化学需氧量等参数进行了全年监测。结果表明:刺参养殖池塘年平均水温为13.69±9.84℃,波动范围为-1.80~26.63℃,水温与初级生产力呈显著正相关性(P0.05)。融冰期水温呈由表层至底层逐渐升高的趋势;盐度年平均值为30.95±2.96,冬季较高,夏季较低。融冰期盐度随水深的增加而升高;年平均p H为7.94±0.17,高温期存在昼夜变化现象;氨氮浓度年平均值为47.42±34.87μg/L,高温期存在明显的垂直和昼夜变化现象;透明度、溶氧量和化学需氧量的年平均值分别为1.03±0.48 m、8.40±1.34 mg/L和17.46±1.75 mg/L。所调查池塘刺参养殖环境条件总体较好,这为高产养殖奠定了基础。 相似文献
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上海市淡水养殖水体中氮、磷的分布研究 总被引：2，自引：0，他引：2
为查明上海市淡水养殖水体中氮、磷分布现状,选取上海市典型的淡水养殖场进行引水和池塘水质监测。结果表明,上海市淡水养殖水体中总氮、总磷年均质量浓度分别为2.53 mg/L和0.294mg/L;引水和池塘水体中总氮平均质量浓度无显著差异(P0.05),池塘水中总磷平均质量浓度为0.370mg/L,显著高于引水;不同养殖品种池塘中氮、磷年均质量浓度有所差异,淡水鱼塘中总氮、总磷平均质量浓度最高,凡纳滨对虾塘次之,中华绒螯蟹塘最低;养殖生产使池塘水体中有机态氮、磷在总氮和总磷中的占比以及氨氮在无机氮中的占比较引水均有所增加;引水中总氮在春、冬季含量相对较高,总磷在夏、冬季含量较高。养殖过程中淡水鱼塘中氮、磷含量因有机质的累积在秋季养殖后期较高;凡纳滨对虾塘中氮、磷含量在5月养殖初期相对较高;中华绒螯蟹塘内氮含量因水草的净化作用随养殖进程逐渐降低;70%以上的引水样品水质综合污染指数高于1.0,淡水养殖的引水质量不容乐观。整体上,淡水鱼的养殖显著增加了水体的综合污染程度(P0.05),凡纳滨对虾和中华绒螯蟹的养殖对水体综合污染程度影响不显著(P0.05)。 相似文献
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通过使用改造后的推水养殖系统养殖草鱼的跟踪养殖实验来验证改造后的推水养殖系统的养殖效果。经过8个月的养殖得到推水养殖养殖槽养殖草鱼成活率为66.64%,规格为225.45g/尾，养殖槽产量为7.25kg/m3。养殖槽中的水温高于大池塘水温，推水养殖系统水体氨氮、总氮和总磷会随着养殖进程而升高，而且均是养殖槽高于尾水处理区出口处，高于大池塘。最高时养殖槽总氮、氨氮和总磷分别达到了7.10mg/L、3.65mg/L、0.58mg/L,大池塘总氮、氨氮和总磷分别达到了3.45mg/L、1.08mg/L、0.21mg/L,尾水处理区出水口总氮、氨氮和总磷分别达到了5.72mg/L、2.11mg/L、0.42mg/L。结果表明改造后推水养殖系统养殖草鱼生长速度没有明显变化，养殖槽内水质仍然难以控制。 相似文献
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适宜的水质对鳗鲡的生存和生长是十分必要的。养鳗池水中的溶解氧、pH、水温、氨氮、透明度、悬浮物含量、浮游生物种类组成及生物量等生态因子的变化都直接或间接影响着鳗姻的摄食、生长和抗病能力。目前,我国的成鳗养殖较多地采用露天自然水温养殖池,池水受自然气候的影响很大,水质变化剧烈,必须严格控制。因而养鳗池水质调控管理是养鳗的关键措施之一,同时也是养鳗高产、稳产的可靠保证。滩涂土池养鳗从80年代中期兴起,是开发我国广阔滩涂的一项良好举措。由于滩涂池塘上质特点及采用的水源多为河口水,水中悬浮物含量较高,水质… 相似文献
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为了解斜带石斑鱼(Epinephelus coiodes)池塘育苗过程中育苗水体水环境理化因子的动态变化规律,采用定点取样的方法对水质指标进行连续监测。结果显示:斜带石斑鱼育苗池塘的水温变化范围为29.5～34.7℃,盐度变化范围在28～32,溶解氧变化范围在4.32～11.56 mg/L,pH的变化范围在7.93～8.78,氨氮的变化范围在0.04～0.38 mg/L,硝酸盐氮的变化范围在0.30～1.00 mg/L,亚硝酸盐氮的变化范围在0.001～0.003 mg/L,总氮的变化范围在0.30～1.50 mg/L,活性磷酸盐的变化范围在0.03～0.11mg/L,总磷的变化范围在0.12～0.52 mg/L,COD变化范围在2.1～3.8 mg/L。试验表明,在斜带石斑鱼池塘育苗周期内保持育苗水体水质指标稳定对提高育苗成活率至关重要。 相似文献
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Association between the interannual variation in the oceanic environment and catch rates of bigeye tuna (Thunnus obesus) in the Atlantic Ocean 
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下载免费PDF全文 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
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Liping Li Rui Wang Wanwen Liang Xi Gan Ting Huang Yan Huang Jian Li Yunliang Shi Honglin Luo Ming Chen 《广西水产科技》2014,(1)
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
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Iciar Martinez Amaya Velasco Ricardo Pérez-Martín Eskil Forås Michiaki Yamashita Carmen G. Sotelo 《Journal Of Aquatic Food Product Technology》2013,22(4):289-297
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
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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
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Growth hormone (GH) and reproduction: a review 总被引：5，自引：0，他引：5
Florence Le Gac Odile Blaise Alex Fostier Pierre-Yves Le Bail Maurice Loir Brigitte Mourot Claudine Weil 《Fish physiology and biochemistry》1993,11(1-6):219-232
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
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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
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Controlled infection of Poecilia reticulata Peters (guppy) with Tetrahymena by immersion and intraperitoneal injection 下载免费PDF全文
下载免费PDF全文 G Sharon M Pimenta‐Leibowitz M C L Vilchis N Isakov D Zilberg 《Journal of fish diseases》2015,38(1):67-74
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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