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1.
Monoculture of sea cucumber (pond S) and polyculture of shrimp with sea cucumber (pond SS) were established to evaluate the effect of shrimp on the environmental conditions of sea cucumber farming pond. Contributions of sediment organic matter (SOM2) resuspended from benthic sediment and the suspended particulate organic matter (SPOM) deposited from the water column to the precipitated organic matter (SOM1) collected with sediment traps were estimated with carbon stable isotope analysis. The results showed that the levels of SPOM and SOM2 in pond SS significantly decreased in comparison with those in pond S at the end of experiment (P < 0.05), indicating that co-culturing shrimp in sea cucumber farming pond could purify the farming water. Carbon stable isotope analysis showed that the proportion of SOM2 in SOM1 in pond SS (84.97% ± 0.38%) was significantly lower than that in pond S (95.20% ± 0.30%) (P < 0.05), suggesting that the resuspension of organic matter from benthic sediment into overlying water was reduced in polyculture pond. In contrast, the proportion of SPOM in SOM1 in pond SS (15.03% ± 0.38%) was significantly higher than that in pond S (4.80% ± 0.30%) (P < 0.05), indicating that the sedimentation of SPOM from water column was enhanced in pond SS owing to the biodeposition effect of shrimp.  相似文献   

2.
In this study we assessed the current status of coral reefs along the Saudi Arabian coast of the Red Sea. Among the three growth forms of Acroporid corals, the branching forms were found to dominate in the Farassan Islands(44.55%±11.10% cover) followed by tabular forms in the Doga Islands(ranging between 18%±6.47% and 18.30%±9.47% cover). Digitate forms were rarely found along the coast except at Maqna. Among the five growth forms of non-Acroporid corals, we observed maximum cover of branching forms in the Yanbu offshore area(58.89%±15.11% cover) followed by the Jeddah coast(24.76%±14.04% cover). The Millepora spp., a non-Scleractinian coral, was abundant at all the near-shore sites, such as Jeddah(10.70%±8.21%) and Al-Wajh(9.81%±6.69%). The live coral cover(including both Scleractinian and non-Scleractinian corals) of Saudi Red Sea coast was seen to be higher in the north and gradually decrease towards the south. Principal Component analysis showed that the contribution of Acroporid corals was greater in the southern region than in the northern and middle regions, but vice-versa in the case of non-Acroporid corals. Bray-Curtis cluster analysis categorized all the study sites into two major clusters with 60% similarity. Among them, one cluster-forming sites from Maqna to Masturah(Northern region) and the second one comprised the middle and southern regions(Jeddah to Farassan Islands), and one outlier Rabigh.  相似文献   

3.
This study investigated the difference of nutrient composition in Caulerpa lentillifera collected from different regions.The nutrient compositions of C.lentillifera from China's Hainan and Shandong provinces were determined and compared with those from Semporna(Malaysia),Sabah(Malaysia),Petchburi(Thailand),and two other species of seaweeds(Malaysia).The results showed that the polysaccharide and protein contents of C.lentillifera from Hainan(44.82%±0.98%and 12.5%±0.70%),Shandong(43.22%±1.42%and 14.7%±0.72%),Petchburi(59.27%±2.31%and 12.49%±0.30%),and Sabah(44.02%±2.01%and 19.38%±1.48%)were higher than those of Eucheuma cottonii(26.49%±3.01%and 9.76%±1.33%)and Sargassum polycystum(33.49%±1.70%and 5.40%±0.07%),respectively.The polyunsaturated fatty acid contents in C.lentillifera from Hainan(29.98%)and Shandong(22.11%)were higher than that in Semporna(16.76%±0.27%),Sabah(9.49%),and S.polycystum(20.34%±0.43%),but lower than that in E.cottonii(51.55%±0.57%).In Caulerpa lentillifera of Hainan and Shandong provinces,the essential amino acid(EAA)/total amino acid(TAA)ratios were 35.22%and 38.78%,respectively;and the EAA/ETAA ratios were 54.36%and 63.35%,respectively.The EAA composition of C.lentillifera was close to the ideal model of Food and Agriculture Organization/World Health Organization.C.lentillifera was rich in mineral elements,including calcium((3315.85±127.55)mg(100 g)^-1 and(3728.35±92.38)mg(100 g)^-1),magnesium((6715.74±82.58)mg(100 g)^-1 and(8128.59±242.72)mg(100 g)^-1),and trace elements,including iron((510.65±5.47)mg(100 g)^-1 and(1972.97±183.35)mg(100 g)^-1),selenium((1.04±0.08)mg(100 g)^-1 and(0.83±0.15)mg(100 g)^-1),and zinc((33.90±0.13)mg(100 g)^-1 and(11.75±2.05)mg(100 g)^-1).These results showed that C.lentillifera was more nutritious than S.polycystum or E.cottonii in terms of polysaccharide,protein,and fatty acid contents.Furthermore,both C.lentillifera species collected from Hainan and Shandong provinces show more basic nutrients.Therefore,C.lentillifera has important development and application prospects.  相似文献   

4.
The effects of different NaCl concentrations, nitrogen sources, carbon sources, and carbon to nitrogen molar ratios on biomass accumulation and polyhydroxybutyrate (PHB) production were studied in batch cultures of the marine photosynthetic bacterium Rhodovulum sulfidophilum P5 under aerobic-dark conditions. The results show that the accumulation of PHB in strain P5 is a growth-associated process. Strain P5 had maximum biomass and PHB accumulation at 2%-3% NaCl, suggesting that the bacterium can maintain growth and potentially produce PHB at natural seawater salinity. In the nitrogen source test, the maximum biomass accumulation (8.10±0.09 g/L) and PHB production (1.11±0.13 g/L and 14.62%±2.25% of the cell dry weight) were observed when peptone and ammonium chloride were used as the sole nitrogen source. NH 4 + -N was better for PHB production than other nitrogen sources. In the carbon source test, the maximum biomass concentration (7.65±0.05 g/L) was obtained with malic acid as the sole carbon source, whereas the maximum yield of PHB (5.03±0.18 g/L and 66.93%±1.69% of the cell dry weight) was obtained with sodium pyruvate as the sole carbon source. In the carbon to nitrogen ratios test, sodium pyruvate and ammonium chloride were selected as the carbon and nitrogen sources, respectively. The best carbon to nitrogen molar ratio for biomass accumulation (8.77±0.58 g/L) and PHB production (6.07±0.25 g/L and 69.25%±2.05% of the cell dry weight) was 25. The results provide valuable data on the production of PHB by R. sulfidophilum P5 and further studies are on-going for best cell growth and PHB yield.  相似文献   

5.
The major population of the veined rapa whelk Rapana venosa(Valenciennes, 1846), which is an important fishery resource, is facing a large decline in China. We studied the effects of incubation temperature(16–34℃ at salinity 30) and salinity(5–45 at 25℃) on the incubation period and subsequent larval development. In the temperature experiment, the shortest incubation period was 12 days at 34℃, the lower temperature limit was 16℃, the longest mean shell length(1 193±17 μm) occurred at 25℃ and the highest survival rate 72.28%±5.62% was observed at 28℃. In the salinity experiment, the shortest incubation period was 15 days at 25. The salinity tolerance range was 15–40, the longest mean shell length(855±9 μm) and the highest survival rate 72.93%±4.85% were both observed at 35. This study demonstrated that, during the egg–mass stage, temperature and salinity regimes infl uence later growth and survival of larvae. These observations deepen our understanding of the ecology and conservation of natural populations of Rapana venosa.  相似文献   

6.
以全鱼粉作为唯一蛋白源(D1),用豆粕替代10%、20%鱼粉(D2、D3),玉米蛋白粉替代10%鱼粉(D4),啤酒酵母替代10%鱼粉(D5),配制5组等氮等能饲料,每种饲料设置3个实验组,进行56 d的养殖实验。通过血液和组织涂(印)片、细胞染色和显微观察,研究人工培育的褐点石斑鱼幼鱼外周血液白细胞的分类组成,头肾、脾脏、体肾和肝脏等4种组织中各类血细胞的发生情况,以及不同蛋白源饲料对褐点石斑鱼血细胞发生的影响。结果表明:褐点石斑鱼外周血液中的白细胞由淋巴细胞(53.30%±4.66%)、血栓细胞(35.69%±3.85%)、嗜中性粒细胞(10.34%±3.14%)、单核细胞(0.28%±0.36%)、浆细胞(0.24%±0.34%)和嗜酸性粒细胞(0.15%±0.27%)组成;组织印迹片中,未成熟的红细胞、淋巴细胞和粒细胞主要在头肾印迹片中出现,未成熟的单核细胞主要在头肾和脾脏印迹片中出现,血栓细胞在肝脏印迹片中数量最多,推断褐点石斑鱼幼鱼主要的造血组织是头肾,其次是脾脏;在4种组织中均观察到浆细胞,在体肾印迹片中观察到嗜碱性粒细胞,在肝脏印迹片中观察到巨噬细胞,在头肾印迹片中还观察到巨大原红细胞。显微观察和数据统计分析的结果都表明,投喂5种蛋白源不同的配合饲料,未对褐点石斑鱼4种组织中血细胞的发生情况造成显著影响。  相似文献   

7.
This study deals with contribution of artificial food pellet and natural food to Chinese prawn (Penaeus orientalis) growth in a semiintensive culture pond. The prawn carbon consumption, budget, and the effects of some factors on the budget were investigated. The results showed that 26.2% of P. orientalis growth carbon came from formulated feed at the initial culture stage (when the prawns were 0.06±0.01 g in wet weight), and was 62.5% when the prawns were 9.56±1.04 g. The remaining part of the growth carbon was derived from organic fertilizer and natural food. The highest growth rate occurred at 20×10-3 salinity. Suitable salinity for culturing Chinese prawn was (20-28)×10-3.  相似文献   

8.
Information of the difference in quality between farmed and wild fish is central to better ensuring fish products produced in aquaculture meet regulatory and consumer requirements.Proximate composition,amino acid and fatty acid profiles,and toxic elements contents of farmed and wild Chanodichthys mongolicus were established and compared.Significantly higher crude protein content while lower moisture content in farmed fish compared to wild fish were observed(P0.05).The percentages of total amino acids(TAA),total essential amino acids(TEAA),total non-essential amino acids(TNEAA)and total delicious amino acids(TDAA) in farmed fish were all significantly higher than those in the wild equivalent(PO.05).Compared to the FAO/WHO recommended reference values,the ratios of TEAA/TAA(39.84%-40.33%) were comparable to 40%and TEAA/TNEAA(66.22%-67.60%) were above 60%.Fatty acid profiles in both fanned and wild C.mongolicus were dominated by monounsaturated fatty acid(MUFA),with farmed fish contained much more MUFA content compared to wild counterpart(P0.05).Notably,wild fish exhibited significantly higher levels of total polyunsaturated fatty acid(PUFA) including eicosapentaenoic acid(EPA) and docosahexaenoic acid(DHA) than farmed fish(P0.05).The EPA(C_(20:5n3))and linoleic acid(C_(18:2n6)) were the predominant PUFA in wild and fanned C.mongolicus,respectively.Moreover,farmed fish displayed an overall lower toxic element levels(As,Cd,Pb and Hg) in comparison with wild fish,and both were far lower than the established limit standard.In conclusion,our results suggest that the nutritional quality of farmed C.mongolicus was inferior to their wild counterpart with respect to fatty acids nutrition,and therefore further studies should focus on the improving C.mongolicus diet in order to enhance the overall nutritional composition.  相似文献   

9.
A growth experiment was conducted on cobia(Rachycentron canadum,initial weight 108.2 g ± 3.0 g) to investigate the effects of dietary corn gluten meal(CGM) levels on the fish growth,whole body composition and protein metabolism in relation to specific gene expression.Five isonitrogenous(crude protein 45%) and isoenergetic(gross energy 20 kJ g 1) practical diets were formulated by replacing 0%(the control),17.5%,35.0%,52.5%,and 70.0% of fish meal(FM) protein with CGM protein.No significant differences were observed in the survival,feed intake(FI),specific growth rate(SGR),feed efficiency(FE) and protein productive value(PPV) among fish fed diets with 0%,17.5%,35.0%,and 52.5% of CGM protein.However,these indices were significantly lower in fish fed the diet with 70.0% of CGM protein than those in fish fed the control diet(P < 0.05).The whole-body crude protein and lipid contents were significantly lower while the whole-body moisture content was significantly higher in fish fed the diet with 70.0% of CGM protein compared with the control group(P < 0.05).When 70.0% of FM protein was replaced by CGM,plasma total protein and cholesterol contents were significantly lower than those in the control group(P < 0.05).Fish fed the diet with 70.0% of CGM protein had significantly lower hepatic insulin-like growth factor I(IGF-I) expression levels than those in the control group(P < 0.05).However,no significant differences were observed in hepatic target of rapamycin(TOR),dorsal muscle IGF-I and TOR expression levels among dietary treatments.Results of the present study indicated that 52.5% of FM protein could be replaced by CGM in the diets without significant influences on the growth,feed utilization and protein metabolism of juvenile cobia.The present results might be useful for developing cost effective and sustainable cobia dietary formulations.  相似文献   

10.
Spatial distribution of phaeopigment and size-fractionated chlorophyll a (Chl a) concentrations were examined in relation to hydrographic conditions in the northern South China Sea (NSCS) during a survey from 20 August to 12 September, 2014. The total Chl a concentration varied from 0.006 to 1.488 µg/L with a mean value of 0.259±0.247 (mean±standard deviation) µg/L. Chl a concentration was generally higher in shallow water (<200 m) than in deep water (>200 m), with mean values of 0.364±0.311 µg/L and 0.206±0.192 µg/L respectively. Vertically, the maximum total Chl a concentration appeared at depths of 30–50 m and gradually decreased below 100 m. The size-fractionated Chl a concentrations of grid stations and time-series stations (SEATS and J4) were determined, with values of pico- (0.7–2 µm), nano- (2–20 µm) and micro-plankton (20–200 µm) ranging from 0.001–0.287 (0.093±0.071 µg/L), 0.004–1.149 (0.148±0.192 µg/L) and 0.001–0.208 (0.023±0.036 µg/L), respectively. Phaeopigment concentrations were determined at specific depths at ten stations, except for at station A9, and varied from 0.007 to 0.572 (0.127±0.164) µg/L. Nano-and pico-plankton were the major contributors to total phytoplankton biomass, accounting for 50.99%±15.01% and 39.30%±15.41%, respectively, whereas microplankton only accounted for 9.39%±8.66%. The results indicate that the contributions of microplankton to total Chl a biomass were less important than picoplankton or nanoplankton in the surveyed NSCS. Different sized-Chl a had similar spatial patterns, with peak values all observed in subsurface waters (30–50 m). The summer monsoon, Kuroshio waters, Zhujiang (Pearl) River plume, and hydrological conditions are speculated to be the factors controlling the abundance and spatial heterogeneity of Chl a biomass in the NSCS.  相似文献   

11.
In this study, the proximate composition and the amino and fatty acid profi les of shrimp Litopenaeus vannamei(prey) and wild and cultured cuttlefi sh Sepia pharaonis(the latter fed the prey) were determined and compared with FAO/WHO recommendations. The resulting scores for isoleucine, phenylalanine+tyrosine, histidine, lysine, threonine, and tryptophan in cultured cuttlefi sh were ≥150. The ratio of EAA(essential amino acids)/nonessential amino acids in cultured cuttlefi sh(0.82) was higher than in the wild form(0.80). All EAA amino acid scores for cultured cuttlefi sh were higher than their wild counterparts, except for histidine and tryptophan. Both groups of cuttlefi sh possessed similar saturated fatty acid content, with the cultured containing much more total(Σ) monounsaturated fatty acids, Σ n-6 polyunsaturated fatty acids(PUFA), and eicosapentaenoic acid(C20:5 n-3) but less Σ n-3 PUFA, arachidonic acid(C20:4 n-6), and docosahexaenoic acid(C22:6 n-3) than their wild counterparts. Therefore, the present results suggest that these cultured cuttlefi sh were better than the wild form for human health. Notably, these results also indicate that the nutritional composition of these cuttlefi sh might have been signifi cantly affected by diet.  相似文献   

12.
The optimal quantity of dietary lysine (Lys) and arginine (Arg), and the optimal ratio of dietary Lys to Arg for Pacific white shrimp Litopenaeus vannamei were investigated. Coated Lys and Arg were added to a basal diet (37.99% crude protein and 7.28% crude lipid) to provide graded levels of Lys and Arg. The experimental diets contained three Lys levels (2.51%, 2.11%, and 1.70% of total diet), and three Arg levels (1.41%, 1.80%, and 2.21% of total diet) and all combinations of these levels were tested. Pacific white shrimp, with a mean weight of 3.62±0.1 g, were randomly distributed in 36 fiberglass tanks with 30 shrimp per tank and reared on the experimental diets for 50 days. After the feeding trial, the growth performance, survival, feed conversion rate (FCR), body composition and protease and lipase activities in the hepatopancreases of the experimental shrimps were determined. The results show that weight gain (WG), specific growth rate (SGR), FCR, body protein, body Lys and Arg content were significantly affected by dietary Lys and Arg (P <0.05) and improved when dietary Lys and Arg levels were 2.11% ～ 2.51% and 1.80%～2.21%, respectively. Protease and lipase activities in the hepatopancreases of the shrimps appeared higher when dietary Lys and Arg quantities were 2.11% ～2.51% and 1.80%～2.21%, although the difference was not statistically significant (P >0.05). Therefore, according to our results, the optimal Lys and Arg quantities in the diet of Pacific white shrimp, L. vannamei, were considered to be 2.11%–2.51% and 1.80%–2.21%, respectively, and the optimal ratio to be 1:0.88–1:1.05.  相似文献   

13.
虾池微藻定向培育及其对养殖环境因子的影响   总被引：2，自引：0，他引：2  
采用微藻三级扩大培养技术,将在对虾养殖池选育的波吉卵囊藻Oocysits borgei引入凡纳滨对虾Litopenaeusvannamei高位养殖池,并检测养殖环境中微藻群落结构、水质因子、对虾抗病力相关因子、对虾生长情况,研究了以微藻生态调控为主的对虾防病技术。结果表明:养殖前、中、后期,波吉卵囊藻平均生物量占浮游植物总生物量分别为98.02%、78.89%和45.12%,成为虾池中的绝对优势种;作为优势种的持续时间长达77 d。波吉卵囊藻为主的微藻群落控制的水质较稳定,实验池氨氮和亚硝酸盐氮浓度较对照池低。对虾的血细胞数、溶菌(LSZ)活力、抗菌活力、超氧化物歧化酶(SOD)和酚氧化酶(PO)均显著高于对照池(P<0.05);血清蛋白含量差异不显著(P>0.05)。实验池对虾生长速度显著高于对照池(P<0.05)。可见,通过微藻的定向培育方法来优化虾池微藻群落结构,可改善养殖环境。  相似文献   

14.
对饲养在相似环境下的罗氏沼虾(Macrobrachium rosenbergii)三群体肌肉营养成分进行了分析和比较,3个群体分别为浙江湖州的人工养殖群体(A)、缅甸引进种子二代群体(B)和“南太湖1号”杂交群体(B-+)。结果表明,3个群体粗蛋白含量的高低顺序依次为:B-+群体(17.57%)、B群体(16.65%)、A群体(15.88%),但三群体之间没有显著性差异(P>0.05);而A群体的粗脂肪含量为2.04%,显著高于B群体的1.24%(P<0.05)。3个群体中,B-+群体的总氨基酸含量、必需氨基酸含量、鲜味氨基酸和脂肪酸中的EPA+DHA含量均为最高,且必需氨基酸指数最高,为68.06;相比之下,A群体的上述各项指标值均较低。可见,以上三群体中杂交种群(B-+)的肌肉营养品质较优,而人工养殖群体(A)的肌肉品质相对较差。  相似文献   

15.
An important raw material for making agar-agar is the seaweedGracilaria, which is distributed worldwide but grows mostly in the natural state in warm tropic and subtropic zones. Some countries have tried in small scale to cultivate the seaweed, but only along the coasts of South China has it been done successfully on a large commercial scale (in pond and raft culture).  相似文献   

16.
Breeding and mass scale larval rearing of clownfish Amphiprion percula is very limited in brackishwater. We designed an indoor program of A. percula culture in brackishwater with a salinity of 24±1, during which the impacts of feed type, water temperature, and light intensity, on the efficiency of its reproduction, were revealed. The fish were accommodated along with sea anemones in fibre glass tanks to determine the influence of brooder diet on breeding efficiency. Higher reproductive efficiency [number of eggs laid (276 22.3 eggs)] was observed when fish were fed live Acetes sp. rather than clam (204 16.4 eggs), trash fish (155 12 eggs) and formulated feed (110 10 eggs). The spawning rate was increased during September and October (water temperature, 28.74 0.55°C) on average of 2.4 spawning per month; and low spawning rate was in January (water temperature, 24.55 0.45°C) on average of 1 spawning per month. Among three light intensities (100, 500, and 900 lx) set to evaluate larval survival rate, larvae showed the highest survival rate (65.5%) at 900 lx. The breeding method specifically in brackishwater developed in the present study is a new approach, will help the people from the regions of estuary and backwater to enhance their livelihood and it will lead to reduce the exploitation from the wild habitat.  相似文献   

17.
Oceans and seas form a large body of water that contains a natural biodiversity. For humans,represents a resource, which makes this a point of interest, from researches to improve the economy. Seaweeds produce many compounds and secondary metabolites that can be used in different fields of industry such as food, agricultural, pharmaceutical and health. Even though seaweeds are ancestral resources, recently it was notorious a global interest in knowing more about its potentials, where biotechnology plays an important role in research. Studies showed that seaweed has many bioactive compounds beneficial to plant development, giving them a great potential as an agricultural fertilizer. Adding seaweeds to the soil provides organic matter, minerals, trace elements, growth plant regulator, metabolites, vitamins, and amino acids and it can work as a soil conditioner. In Portugal, the use of seaweeds for agriculture is important since long time ago. In the past, populations that lived near coastal zone depended on the seaweeds as a family subsistence but, throughout the years, synthetic fertilizers replaced seaweeds. Our work aimed to assess the potential of the extracts obtained from Ascophyllum nodosum and from Sargassum muticum as an agricultural fertilizer.This evaluation was carried out with rice plants(Oryza sativa) and lettuce(Lactuca sativa), in germination bioassays, the culture of rice and lettuce plants in pots, and culture of lettuce plants in hydroponics. For that, seaweed liquid extracts were used in different concentrations in different bioassays. Results show that extracts obtained from two seaweeds, A. nodosum and S. muticum, can be promissory plant biofertilizer at a concentration of 25% and had a positive effect on seed germination, plant development, and production.  相似文献   

18.
We evaluated the effects of supplemental coated and crystalline methionine （Met） on the growth performance and feed utilization of juvenile cobia （Rachycentron canadum Linnaeus） in a 60-d feeding trial. Fish groups were fed one of six isonitrogenous and isolipidic diets： 1） fishmeal control; 2） un- supplemented experimental （low-fish-meal diet deficient in Met）; or 3） one of four Met diets supplemented with crystalline L-Met, cellulose-acetate-phthalate coated L-Met, acrylic-resin coated L-Met, or tripalmitin- polyvinyl alcohol coated L-Met. The test diets were fed to triplicate groups of cobia （initial body weight 5.40-4-0.07 g） twice a day. The weight gain and specific growth rate of the fish fed the RES diet were highest among the Met-supplemented groups and were 23.64% and 7.99%, respectively, higher than those of the fish fed with the un-supplemented experimental diet （P〈0.05）. The protein efficiency ratio of the fish fed the MET diet was significantly higher than that of the fish fed the un-supplemented experimental diet and the fish in the other methionine supplementation groups （P〈0.05）. Our results suggest that supplementation of crystalline Met in low-fish-meal diets promotes the growth performance of juvenile cobia.  相似文献   

19.
Two modes of regulating the water quality of experimental ponds in indoor raceway culture of Litopenaeus vannamei were evaluated using simple water treatment facilities. A self-made water purifying net, aeration stone, composite microbe preparation, and Ceratophyllum demersum were placed in the experimental ponds and the culture water was circulated along the raceway inside the pond using a paddle wheel aerator. In addition, the water quality in the experimental pond was improved by draining effluent from the pipeline at the bottom of ponds 7 and 8 (mode I) and exchanging the circulating water in pond 10 (mode II) with the reservoir water in pond 9 using a pump and pipeline. The water quality in the experimental ponds was similar in response to regulation using mode I or mode II. Water quality parameters in the experimental ponds were controlled within a suitable range by simple facilities during culture period without using any chemical treatments. The rich content of dissolved oxygen was maintained by the circular flow and continuous aeration of the pond water. The respective average values of the main water parameters in experimental ponds 7 and 10 in response to regulation of the water quality using modes I and II were as follows: pH 8.17 and 7.99; DO 5.16 mg/L and 5.97 mg/L; CODMn 18.45 and 12.61 mg/L; TAN (NH3-N) 0.854 mg/L (0.087 mg/L) and 0.427 mg/L (0.012 mg/L); NO2-N 0.489 mg/L and 0.337 mg/L. Moreover, the average body length and body weight of harvested shrimp of pond 7 and pond 10 were 7.56 cm and 8.99 cm, 5.10 g and 8.33 g, respectively. Furthermore, the survival rate, average biomass yield and average condition factor of the shrimp harvested were 70% and 60%, 2.54 kg/m2 and 2.14 kg/m2, and 0.675 g/cm and 0.927 g/cm, respectively. Linear equations describing the relationship between body length and culture time and cubic or power functions describing the relationship between body weight and body length were obtained based on evaluation of the growth data of shrimps throughout the culture period.  相似文献   

20.
The ion-transport enzyme activities were studied in the nauplii 1–2, zoea 1–3, mysis 1–3, and postlarva 1–7 of the shrimps Marsupenaeus japonicus and Fenneropenaeus chinensis. The results showed that total ATPase, Na+-K+-ATPase, and V-ATPase (V-type H+-ATPase) activities increased during the early development for both the species, from zero in nauplii to stable levels after zoea stage. The enzyme activities of the latter species were significantly higher than those of the former species after zoea stage (F>F 0.05). The contributions of Na+-K+-ATPase, V-ATPase and HCO3 −-ATPase to the total ATPase activity of the two species varied in different developmental stages and accounted for 40%–70%, 22%–46% and 2%–13% in M. japonicus from zoea to postlarva stage, whilst the shares of them were 42%–69%, 28%–44% and 2.5%–22%, respectively in F.chinensis. These findings suggest the possible culture of the two species with varying water quality, especially the salinity and pH.  相似文献   

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