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1.
《齐鲁渔业》2014,(11):I0001-I0001
Added bagasse and Bacillus sp. to Litopenaeus vannamei intensive culture tank, the treatment groups were treatment A（added Bacillus sp.）, treatment B（added Bacillus sp. with crushing bagasse） and treatment C（added Bacillus sp. with crushing-steaming bagasse） respectively. To estimate the effect of addition of bagasse with Bacillus sp. on the culture environment and shrimp growth, the level of total ammonia nitrogen（TAN）, nitrite nitrogen and nitrate nitrogen, total amount of bacteria in the water and shrimp growth were determined. The result suggested that the TAN concentration in treatment B and C were significantly lower than that in treatment A during the early stage of the culture（P〈0.05）. The addition of bagasse with Bacillus sp. was contribute to the formation of bio-floccules. The concentration of bio-floccules in treatment B and Cwere 6.3-20 ml/L and 8.3-30 ml/L respectively, which were significantly higher than that in treatment A（2.7-8.3 ml/L） during the culture（P〈0.05）.The average weight of shrimp in treatment B and C were 8.56±0.21g and 8.84±0.26g respectively, which were significantly bigger than that in treatment A（7.66±0.40g） when harvest（P〈0.05）. 相似文献
2.
The biological cleaning agent Pondplus was dowsed each ten days at different dosage into breeding ponds for Chinese mitten crab with stocking rate at 12 000 ind./ha, to evaluate its purification effects on water environment in breeding ponds and its effects on Chinese mitten crab growth. The results showed that dousing treatment improved the water quality significantly as evaluated according to the parameters of DO, CODMn, NH4 ＋ - N and NO2 - -N. Particularly, when the air temperature was higher than 35℃, the diurnal observation on DO values at the bottom of ponds showed that dousing at 450 g/（ ha•m） gave a DO value higher than 4 mg/L all day long, which was 2 mg/L higher than that of control. The observed increase of Chinese mitten crab were 14. 9% , 27.8% , 27.8% by average weight, when dousing at 150, 300, 450 g/（ha • m） , respectively. Accordingly, the production increased by 8.5%, 11.9%, 18.6% through its promotion of Chinese mitten crab growth, and the economic efficiency were enhanced by 96.2% , 159.8% , 180.9%. 相似文献
3.
Four primary zooplankton species in Taolinkou reservoir located at Qinglong fiver in Qinglong Manchu county in Hebei province were investigated from April 2007 to March 2008, and the zooplankton species and anniversary distribution were concluded. The results showed that in the investigating period 57 kinds of zooplankton were totally found with protozoa 16, rotifera 22, cladocera 12 and copepoda 7, the forms and the preponderant species were different in different months. The average quantity of zooplankton in each month was 185.90 ind./L. The maximum quantity appeared at the earlier autumn. The average quantity （513.60 ind./L） of all sampling stations raised to its peak in August. The quantity was increasing with the temperature in spring and summer, decreasing after September, and lowest in winter. The average biomass was 1.68 mg/L which was the same diversification as the average quantity. 相似文献
4.
3种沉水植物对水华藻类生长的影响 总被引：11，自引：0，他引：11
Effects of three submerged macrophytes, Potamogeton crispus, Myriophyllum sp. and Ceratophyllum demersum on the growth of bloom algae were investigated. The results of the coexistence assay indicated that, Potamogeton crispus, Myriophyllum sp. and Ceratophyllum demersum inhibited significantly excessive growth of bloom algae. Of the three submerged macrophytes, Potamogeton crispus and Myriophyllum sp. have the stronger inhibition on bloom algae; at the relatively higher concentrations （Potamogeton crispus, Myriophyllum sp. and Ceratophyllum demersum fresh weight 80,80 and 160 g/L）, the aqueous extracts of fresh tissue of three submerged macrophytes can inhibit growth of bloom algae ; the growth of bloom algae was strongly inhibited by using dry powder; at the concentration of dry weight 20 g/L, the inhibitory effect by aqueous extracts of the dry powder of the three submerged macrophytes was beyond 50% ; the methanol extracts of the dry powder of three submerged macrophytes can inhibit growth of bloom algae at the relatively higher concentration. 相似文献
5.
《齐鲁渔业》2014,(9):I0001-I0001
Induction of Settlement and Metamorphosis of Sea Cucumber Apostichopus japonicus larvae by 5-HT Yang Ding-long et al. （ 1 ）
Abstract The larva Apostichopus japonicus individuals were exposed to solutions of 5-HT at different concentration. After induction, the rates of metamorphosis were then estimated. The results showed that 5-HT at the concentration 0.001, 0.01, 0.1, 1 mmol/L could increase the metamorphosis rate of sea cucumber larva after 12 h and 24 h induction. The optimum inductive effect of 5-HT was archived when the larva individuals were exposed in 0.1 mmol/L for 24 h, with the metamorphosis rate increment of 12.8 percentage. Key words 5-HT; sea cucumber larvae; metamorphosis; settlement 相似文献
Abstract The larva Apostichopus japonicus individuals were exposed to solutions of 5-HT at different concentration. After induction, the rates of metamorphosis were then estimated. The results showed that 5-HT at the concentration 0.001, 0.01, 0.1, 1 mmol/L could increase the metamorphosis rate of sea cucumber larva after 12 h and 24 h induction. The optimum inductive effect of 5-HT was archived when the larva individuals were exposed in 0.1 mmol/L for 24 h, with the metamorphosis rate increment of 12.8 percentage. Key words 5-HT; sea cucumber larvae; metamorphosis; settlement 相似文献
6.
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
7.
草鱼加热过程中肌肉蛋白质的热变性 总被引：7，自引：0，他引：7
The variations of muscle tissus, peroxidase and Ca2^2 -ATPase activities and Vp (pasteurization value) were investigated with the fresh samples of grass carp ( Ctenopharyngodon idellus ) heated at different temperatures, thus revealing the mechanism of denaturation of muscle protein by heating. The experimental results showed the great difference in muscle tissue structure before and after the samples heated. In the initial stage of heating the water loss accounted for 50% of the total. When the samples were separately heated at 75, 85, and 95℃, fk values (dehydration curve slope) were 5, 4.1 and 1.7, respectively, while Vp reaching 40 minutes were 22, 8 and 5 min, respectively. As to the time for deactivation of peroxidase in the heated samples at the various temperatures, it varied from 38, 10 and to less than 6 min, respectively and the deactivation rates of Ca^2 -ATPase in 1 min were 50%, 88% and 100%, respectively. Consequently, the higher temperature the sample was heated, the faster rate of thermocon ductivity, the lower rate of water loss, and the faster rate of peroxidase deactivation it was. Also, the Vp for the least requirement of pasteurization ( Vp≥40min) was obtained. 相似文献
8.
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
9.
大菱鲆胚胎的玻璃化冷冻保存 总被引：3，自引：0，他引：3
Vitrification solutions were examined for their suitability of cryopreservation of turbot (Seophthulnms maximus) embryos. PMPI gave higher survival rate (75.68%) than other vitrification solutions and was considered to be suitable liar the cryopreservation of turbot embryos. The freezing point of the vitrification solutions consisted of PG and MeOH in the proportion of 3:2 was measured when the vitrification solutions were cryopreserved. It showed that the vitrification solutions with a cryoprotectant concentration of over 41% have no freezing point and the freezing points of vitrification solutions containing 33.33%-40% cryprotectants were between -32.4℃ and -65.4℃, The freezing point decreased with the increase of cryoprotectant concentration. The resistance of turbot embryos at different stages to the cryoprotectants was studied, It was found that the turbot embryos from 4-5 pairs somite to tail bud were more resistant to cryoprotectants and suitable to vitrify. A live embryo was obtained after cryopreservation in liquid nitrogen for 14h and was hatched out。 相似文献
10.
The purpose of this paper is to evaluate the effect of Zhiqi Fungal Substance on their performance, immunity , and meat quality in Macrobrachium rosenbergii. Macrobrachium rosenbergii were allotted into four groups randomly. The control group were fed with basal diet, the others were the treated groups fed with basal diet supplemented with 0.25% ,0.5% ,1% Zhiqi Fungal Substance for 35 days, respectively. The results showed Zhiqi Fungal Substance can imporve the production of shrimpand and the survival rate. Zhiqi Fungal Substance increased the LSZ and SOD level（P 〈 0. 05） compared to control. Addition of 0.5% and 1% Zhiqi Fungal Substance increased the AKP and the ACP level（P 〈 0. 05）. It is indicated that dietary Zhiqi Fungal Substance can improve the flavor of cultured shrimp. 相似文献
11.
氮磷浓度对雨生红球藻叶绿素荧光参数的影响 总被引：1，自引：1，他引：0
在一次性培养过程中,利用水样叶绿素荧光仪(Water-PAM)研究了2个单因子(不同氮浓度、不同磷浓度)对雨生红球藻(Haematococcus pluvialis)叶绿素荧光参数(PSⅡ的最大光能转化效率Fv/Fm、光合电子传递效率ETR)、叶绿素相对含量及细胞密度的影响。单因子方差分析结果表明,氮磷浓度对雨生红球藻的叶绿素荧光参数及生长均有显著的影响(P<0.05)。多重比较结果表明,雨生红球藻进行光合作用和生长最适氮浓度为1760μmol/L;最适磷浓度为18.16μmol/L。相关性分析结果表明:在整个培养周期中,叶绿素相对含量均与细胞密度呈显著的正相关关系。 相似文献
12.
A 68‐day growth trial was conducted in a flow‐through system to determine the effect of dietary manganese levels on growth and tissue manganese concentration of juvenile gibel carp (Carassius auratus gibelio). Seven purified diets containing 7.21, 8.46, 9.50, 10.50, 13.03, 19.72 and 22.17 mg manganese (as manganic sulfate) per kilogram diet were fed to triplicate groups of fish (initial weight 3.21 ± 0.01 g). The results showed that dietary manganese levels did not significantly affect feed intake of the fish. Specific growth rate, feed efficiency, total hepatic superoxide dismutase activity, carcass and skeletal manganese concentration increased significantly with increased dietary manganese(P < 0.05) while condition factor decreased significantly(P < 0.05). It was concluded that dietary requirement of manganese was 13.77 mg Mn per kilogram diet. Carcass and skeletal manganese concentration could also be used to evaluate the manganese requirement. Total hepatic superoxide dismulase activity was not a sensitive indicator for dietary requirement. 相似文献
13.
- 1. Under the Endangered Species Act, the National Marine Fisheries Service has authority to protect listed species from any adverse actions that may jeopardize the population's ability to recover and increase to sustainable levels. Listed salmon species in the northwest United States are known to travel through urban areas in their migration from river to ocean. Species such as the chinook salmon (Oncorhynchus tshawytscha) often spend several weeks in these urban estuaries where they can be highly exposed to urban‐related contaminants that reside in the sediments and accumulate in their prey species. The concern is that these contaminants are bioaccumulated to levels that may impact the ability of individual salmon to grow and mature normally. This paper provides a framework for determining the tissue and sediment concentrations of polychlorinated biphenyls (PCBs) that are likely protective against adverse effects in listed salmonid species.
- 2. The relevant ecotoxicological literature was examined and 15 studies were selected that met the pre‐established criteria outlined here. For each study, the lowest tissue concentration (residue) of total PCBs associated with a biological response was selected. The tissue concentration associated with the 10th percentile of these 15 studies was chosen to represent the residue effect threshold (RET) above which wild juvenile salmonids would be expected to exhibit adverse sublethal effects from accumulated PCBs. This value (2.4 μg PCBs g?1 lipid) is expressed in terms of the lipid‐normalized concentration because of the large effect lipid can have on the expressed toxicity and the substantial variability in lipid content observed in salmonids over their life cycle.
- 3. A sediment concentration that is expected to produce the RET was then determined using the biota‐sediment accumulation factor approach. The sediment effect threshold, which varies with the total organic carbon content in sediment, is the level above which adverse effects may be expected in juvenile salmonids due to accumulation of PCBs from environmental exposure. Bioaccumulation of PCBs was examined in one river system as a model for determining an appropriate bioaccumulation factor for wild juvenile chinook salmon.
- 4. Evaluation of exposure to potentially deleterious concentrations of PCBs based on tissue residues is the preferred approach; however, the sediment effect threshold may also be used in cases where bioaccumulation has been characterized in an estuary. The threshold values presented here are intended as interim guidelines that should be modified as more data become available. Additionally, because of the uncertainty around many of the factors and assumptions that comprise the single threshold effect values, it is recommended that future studies be employed to help determine a range of acceptable values that would afford protection under various environmental and biological conditions.
14.
不同温度与饵料浓度下菲律宾蛤仔的能量收支 总被引：8，自引：1，他引：8
在静水系统中测定了实验条件下菲律宾蛤仔(Ruditapes philippinarum)的摄食率、吸收率、耗氧率和排泄率等生理指标;研究了软体部干重、温度和饵料浓度对菲律宾蛤仔最小碳需求量(WMCR)和能量收支的影响;建立了不同温度及饵料浓度下菲律宾蛤仔的能量收支方程。结果表明：最小碳需求量随个体软体部干重的增加而增加,温度越高其增加速率越快;软体部干重对生长效率没有显著的影响。温度通过影响耗氧率而显著影响单位软体部干重的最小碳需求量。在9—22℃范围内,菲律宾蛤仔的生长余力(SFG)随温度和饵料浓度的升高而增加,在较低温度和饵料浓度下蛤仔的SFG均出现负值。在能量收支方程中摄食能随温度变化显著,而呼吸耗能随温度的变化不明显。 相似文献
15.
硫酸铜和高锰酸钾对似刺鳊鮈幼鱼的急性毒性试验 总被引：3，自引：0，他引：3
室温条件下,用静水生物测试法,分别用硫酸铜和高锰酸钾对似刺鳊鮈幼鱼的进行急性毒性试验。结果显示,硫酸铜和高锰酸钾对似刺鳊鮈幼鱼24h的LC50值分别为0.6148mg/L和1.5987mg/L;48h的LC50值分别为0.5517mg/L和1.1637mg/L;72h的LC50值分别为0.4950mg/L和0.9906mg/L;96h的LC50值分别为0.4698mg/L和0.9828mg/L。硫酸铜和高锰酸钾对似刺鳊鮈幼鱼的安全浓度分别为0.04698mg/L和0.09828mg/L。似刺鳊鮈幼鱼对硫酸铜和高锰酸钾的耐受力:高锰酸钾>硫酸铜。似刺鳊鮈人工养殖疾病防治过程中,硫酸铜和高锰酸钾消毒药液须慎用。 相似文献
16.
Rui‐Bing Peng Peng‐Shuai Wang Ke‐Xin Le Yuan Wang Qing‐Xi Han Xia‐Min Jiang 《Journal of the World Aquaculture Society》2017,48(4):602-610
The aim of this study was to provide a reference value for the safe regulation and control of ammonia nitrogen in the aquaculture of Sepia pharaonis. The effects of acute and chronic toxicity of ammonia on the cuttlefish, S. pharaonis, were tested experimentally using juvenile S. pharaonis. The results showed that the half‐lethal concentration (LC50 ) values of ammonia nitrogen in juvenile S. pharaonis with a body weight of 6.52 ± 0. 23 g at 24, 48, 72, and 96 h were 31.72, 25.77, 23.33, and 18.33 mg/L, respectively, and the corresponding un‐ionized ammonia nitrogen (UIA‐N) concentrations were 1.66, 1.35, 1.22, and 0.96 mg/L, respectively. Compared with the control, the survival rate, specific growth rate, and feed intake of juvenile S. pharaonis declined significantly, and the feed conversion ratio and hepatosomatic index increased significantly at 56 d after exposure to >1 mg/L ammonia nitrogen. Juvenile S. pharaonis should be maintained at a concentration of ammonia nitrogen of no more than 1 mg/L (UIA‐N is 0.056 mg/L) in culture, and removing harmful nitrogenous wastes from the seawater is critical in maintaining cuttlefish culture. 相似文献
17.
The minimum inhibitory concentrations (MICs) of 15 chemotherapeutic agents were tested against 146 Lactococcus garvieae strains isolated from 1999 to 2006 in Japan. The agents used included chloramphenicol, ciprofloxacin, erythromycin (EM), enoxacin, fleroxacin, florfenicol, kanamycin, lincomycin (LCM), norfloxacin, oxolinic acid, orbifloxacin, ofloxacin, benzylpenicillin, streptomycin and tetracycline (TC). Of the tested strains, 46 showed high levels of resistance to EM, LCM and TC. Twelve of these strains were detected to be carrying transferable R-plasmids using a conjugation experiment and, using Southern hybridization, were shown to have the same structure as the R-plasmid. The remaining 34 resistant strains had a similar DNA structure to that of the R-plasmid as confirmed by polymerase chain reaction (PCR) using primers designed from sites in the transferable R-plasmid. The EM and TC resistance genes were classified into the ermB and tetS groups using PCR. We also detected gyrA and/or parC mutants that are highly resistant to old and new generation quinolones. This study revealed that transferable R-plasmids encoding EM, LCM and TC are widely distributed and are conserved regardless of the area and/or time of collection. 相似文献
18.
The ecosystem carrying capacity for aquaculture cage farming in South Australia is based on guidelines that the maximum feed rates (and farmed fish biomass) be determined such that the concentration c of a given dissolved nutrient does not exceed a prescribed value (say cP). The problem then is one of relating the nutrient flux F, due to feeding, to the tracer concentration c. To this end the evolution of concentration is modelled using the depth-averaged advection–diffusion equation for a constant source flux F over a finite area cage (or lease) and for both constant and time dependent (tidal) velocities. The divergence theorem is applied to this equation to obtain a new scale estimate of the relation between the flux F and the maximum concentration cmax of a nutrient in the cage region: cmax ≈ F·T*, where T* is a time scale of cage “flushing” that involves both advection and diffusion. The maximum allowed nutrient flux F (and carrying capacity of fish biomass) can then be simply estimated from: F ≈ cP/T*. New semi-analytic solutions of the advection–diffusion equation for a finite (cage) source are then derived to explore the physics of concentration evolution for constant and tidally varying currents, and to show that the estimate cmax ≈ F·T* is surprisingly robust and generally within 40% of the exact values for a wide set of advective/diffusive parameters. The results generally should find application in other finite source flux problems in the coastal oceans including desalination plants and waste water outfalls. 相似文献
19.