Water Filterable and Particulate Metals and Their Bioaccumulation in Prawns along Veifa Village, Central Province, Papua New Guinea

Toxic metals are released into the river systems from both anthropogenic activities and natural sources. These metals are present in water as filterable and particulate metals. These metals were found to bioaccumulate in prawn samples along Veifa stretch of the Angabanga River. The analytical results showed that As as particulate metal was high in concentration at 86 μg·g^-1 and Pb as filterable metal was high in concentration at 12 μg·g^-1. The metals Pb and As also accumulated in prawns along the Veifa stretch but were within recommended toxic metal standards.

Bioaccumulation of polychlorinated biphenyls in prawns and a mud crab from mixed-aquaculture ponds

The bioaccumulation of ten polychlorinated biphenyl （PCB） congeners was investigated within different tissues in three prawns （Penaeusorientalis Kishinouce, Laomedia astacina de Haan and Penaeus vannamei Boone） and one mud crab （Scylla serrata Forsskal） from mixed-aquaculture ponds in Taizhou in April 2007. The average concentrations （wet mass） of ∑ PCBs in muscle, head, and rind tissues for mean among these prawn species were 7.04, 21.16, and 11.47 ng/g, respectively. The average concentrations of ∑ PCBs in muscle, branchia, and spawn in Scylla serrata were 6.49, 21.13, and 19.76 ng/g, respectively. The concentrations of CB28 were the highest in prawn tissues （2.40 ng/g）, and accounted for 18.60% of ∑ PCBs. The concentration of CB52 was the lowest. The application of principal component analysis （PCA） for the estimation of PCB sources of contamination resulted in first component main contributions of CB101, CB153 and CB28 in the muscle, head, and rind in combined prawn samples, respectively. The enrichment level of PCBs for different tissues varied greatly. The accumulation coefficient of ∑ PCBs in prawn muscle, head, and rind tissues were 396.35, 1 191.79, and 645.91, respectively. For the Scylla serrata, the accumulation coefficients were 365.81, 1 190.50, and 1 113.31 for muscle, branchia, and spawn tissues, respectively. For prawns, the accumulation coefficient of CB153 was the highest in muscle tissues, while CB155 had the highest coefficients in the head and rind tissues. The CB155 coefficient was the highest in spawn tissues of the mud crab.

Prawns in Bamboo Tube

Ingredients: 400 grams Jiwei prawns, 25 grams pork shreds, 5 grams sliced garlic. Condiments: 5 grams cooking oil, minced ginger root and scallions, cooking wine, salt, pepper and MSG (optional) Method: 1. Place the Shelled prawns into a bowl and mix with all the condiments. 2. Stuff the prawns into a fresh bamboo tube,

Bright Prawns

Ingredients: 750 grams of prawns Supplementary ingredients: eggs, ginger, salt, wine and haw jam Directions: 1. Cut off the antennae and devein prawns. Cut off heads and tails. Marinate the prawns in wine.

Application of alginate oligosaccharide produced by enzymatic hydrolysis in the preservation of prawns

Alginate oligosaccharide(AOS)was enzymatically prepared and had a degree of polymerization(DP)of 2-6.AOS exhibited evident antioxidant efficacy in ABTS+scavenging activity,hydroxyl radical scavenging capacity,and total reducing power.The freshness of the prawns,which were treated with AOS andε-polylysine(ε-PL),was evaluated by measuring indicators such as total viable bacteria(TVC),pH,total volatile basic nitrogen(TVB-N),sensory,texture,and melanosis during storage period.The texture properties and sensory scores of prawns treated with AOS andε-PL were significantly improved(P<0.05)in comparison with the control group.Meanwhile,the increase in TVC,pH,TVB-N,and melanosis scores of prawns treated with AOS andε-PL were effectively delayed(P<0.05)in comparison with control group.Moreover,the quality of prawns treated with 8 g/L AOS was better than that of prawns treated with 6 g/L.AOS could prolong the shelf life of prawns by 2 days at least.Therefore,AOS is a natural biological preservative in providing an effective and safe way to preserve freshness of prawns.

鱼粉蛋白与发酵酶解豆粕蛋白不同配比对日本沼虾生长及免疫性能的影响

本试验旨在评价补充微囊氨基酸条件下鱼粉蛋白和发酵酶解豆粕蛋白不同配比对日本沼虾生长和免疫性能的影响。试验配制5组等氮等能饲料,以发酵酶解豆粕分别替代饲料中0(FM组)、25%(R25组)、50%(R50组)、75%(R75组)以及100%的鱼粉(R100组)(鱼粉蛋白与发酵酶解豆粕蛋白配比分别为1∶0、3∶1、1∶1、1∶3和0∶1),对平均体重为(0.103 0±0.000 2)g的日本沼虾进行8周的饲养试验,随后对各组虾进行嗜水气单胞菌感染试验。每组设5个重复,每个重复50尾虾。结果表明:当鱼粉蛋白与发酵酶解豆粕蛋白配比为1∶1时,日本沼虾的增重率达到最大,显著高于FM和R100组(P<0.05),各组日本沼虾的存活率无显著差异(P>0.05);各组日本沼虾的肝胰腺超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活力及丙二醛(MDA)含量无显著差异(P>0.05);FM组日本沼虾的血细胞总数及血淋巴吞噬活性均显著高于R100组(P<0.05);肝胰腺中热应激同源蛋白70和热应激蛋白90的mRNA相对表达水平分别在FM和R25组达到最高,显著高于其余各组(P<0.05);当发酵酶解豆粕替代鱼粉比例超过50%时,嗜水气单胞菌感染后日本沼虾的累计死亡率显著增加(P<0.05)。由此可见,发酵酶解豆粕可作为日本沼虾饲料中较好的蛋白质源,在氨基酸平衡条件下鱼粉蛋白和发酵酶解豆粕蛋白的最佳配比为1∶1。

罗源湾对虾产卵场调查

随着罗源湾沿岸对虾养殖面积的扩大,对海区对虾亲虾的需求量也不断地加大,这就导致大量捕捞亲虾,引起对虾资源的严重衰退。为了更好地保护和开发对虾资源,调查了连江、罗源及宁德三个县对虾育苗场在罗源湾收购对虾亲虾数量,同时,对虾部分亲虾进行体重、性比及成熟度的测量,从而了解该湾对虾亲虾资源量,此外,还访问有关水产单位和渔民捕虾数量及分布位置,并且结合罗源湾浮游动物调查样品分析资料,综合分析罗源湾对虾产卵场及对虾的来源,以便为今后对虾资源的保护和增殖放流提供参考,兹将调查结果和建议简述如下:

Detection of prawn white spot baculovirusby polymerase chain reaction

INTRODUCTIONAprawnbaculovirushasbeenresponsibleformostoftheseriousshrimpdiseaseinChinasince1992.Studiesonthepathology,Pathogenesisandmorphologyofthevirusshowedthatitwasanon-occlUSiontheybaculoviruswhichcouldinfectPenaeusjaponicus,P.nzonham,P.chinests...

Effect of salinity on growth and first sexual maturity of Exopalaemon carinicauda(Holthuis, 1950)

To determine the optimal salinity for growth and first sexual maturity of ExopaIaemon carinicauda, the effects of salinity on growth and reproductive performance of early juvenile prawns of E. carinicauda were evaluated under laboratory conditions. Postlarvae from the same female broodstock were reared at six salinity levels （5, 10, 15, 20, 25, and 30） for 12 weeks. The specific growth rate （SGR） and survival rate （SR） under different salinity levels in the first 6 weeks were calculated and compared. SGR was significantly influenced by salinity. Prawns reared in salinity of 10 grew significantly faster （P〈0.05） than those reared in salinities of 5, 20, 25, and 30. However, ANOVA confirmed that there was no significant effect among the six salinity levels on SR. For the next 6 weeks, the body length （BL）, body weight （BW） at the first sexual maturity, and the age at median sexual maturity （As0） of females were measured and compared. Female prawns reared at salinity of 10 presented significantly shorter A50, but no significant differences among the six salinity levels for BL and BW at the first sexual maturity were observed. Based on the above information, the optimal salinity for growth and first sexual maturity of juvenile E. carinicauda is approximately 10.

TOXIC EFFECTS OF Zn^(2+), Cu^(2+), Cd^(2+)and NH_3 ON CfflNESE PRAWN

This study deals with the toxic effects of Zn2+, Cu2+, Cd2+ and NH3 on Chinese prawn (Penaeus orientalis). The median lethal concentrations of the toxic matters on Chinese prawn were determined. Cd2+】Cu2+】Zn2+】NH3-Nm is the toxic order of these chemicals to Chinese prawn. The toxic order of concentrated Zn2+ and Cd2+ in tissues and organs of Chinese prawn is in the order gill 】 shell + appendage】viscera 】 muscle..

A STUDY ON PATHOGENS OF CHINESE PRAWN (PENAEUS CHINENSIS) VIRUS DISEASES

This pathogenic study shows that the viral diseases of Chinese prawns (Penaeus chinensis. O’sbeck)is due to three kinds of viruses: epithelium envelope baculovirus of Penaeus chinensis (EEBV-PC, de-tected by the authors in 1993), infections hypodermal and hematopoietic necrosis virus, andhepatopancreatic parvo-like virus, and that the first two viruses seem to be the main pathogens of theepidemic in the northern regions in 1993.

Effect of Sodium Tri Polyphosphate (STPP) and Foreign Materials on the Quality of Giant Freshwater Prawn (<i>Macrobrachium rosenbergii</i>) under Ice Storage Condition

There are reports on the use of chemicals like sodium tri polyphosphate (STPP) and foreign materials like pearl tapioca (locally called ‘sagu’), jelly (litchi) to adulterate freshwater prawn (Macrobrachium rosenbergii) prior to freeze processing to increase their weight. Studies were, therefore, undertaken to determine the changes in product quality on the use of different concentrations of STPP, sagu and litchi under ice storage condition. Percent weight gain of prawn was 5.46, 18.87 and 23.50 when dipped in 2%, 4% and 6% STPP solution, respectively. In all cases maximum water uptake by prawn muscle was during the first 6 h with fastest weight gain with STPP solutions containing tap water compared to those of ice and tap water. Organoleptic quality of the STPP treated samples became brown and spongy after 8 h of dipping treatment under iced condition. Quality assessment studies conducted after injecting sagu and litchi in prawn muscle showed little or no difference with those of control samples during the first 6 h, which turned whitish and swollen with severe drip loss after 24 h of ice stored condition, indicating characteristics for easy identification of the injected shrimps by organoleptic method.

Vibrio spp.from Macrobrachium amazonicum prawn farming are inhibited by Moringa oleifera extracts

Objective:To investigate the in vitro antimicrobial potential of extracts of stem,leaves,flowers,pods and seeds of Moringu okifera(M.okifera) against Vibrio spp.from hatchery water and the prawn Mmrobrachium amazonicum.Methods:The ethanol extracts of stem,leaves,pods and seeds and chloroform extract of flowers of M.oleifera were tested against Vibrio cholerue(V.cholerae) serogroups non-O1/non-O139(n=4).Vibrio vulnificus(n=l) and Vibrio mimicus(n=1).Escherichia coli(E.coli)(ATCC(?) 25922) was used as quality control.Vibrio species were obtained from Macmbrachium amazonicum prawns and from hatchery water from prawn farming.The Minimum Inhibitory Concentration(MIC) was determined by broth microdilution method.Results:The best result was obtained with the ethanol extract of pods,which inhibited three strains of the V.choleme,Vibrio vulnificus,Vibrio minimis and E.coli(MIC range 0.312-5.000 mg/mL).The chloroform extract of flowers was effective against all V.chokrae strains and E.coli(MIC range 0.625-1.250 mg/mL).However,the ethanol extracts of stem and seeds showed low effectiveness in inhibiting the bacterial growth.Conclusions:The extracts of pods,flowers and leaves of M.oleifera have potential for the control of Vibrio spp.Further studies are necessary to isolate the bioaetive compounds responsible for this antimicrobial activity.

RELATION BETWEEN WATER TEMPERATURE, WATER EXCHANGE AMOUNT, FEED AND PRAWN DISEASE

High temperature is an important factor inducing bacterial disase of the prawn (Penaeus orientalis).Water temperature over 35℃ apparetly stopped tested baculovirus from multiplying. High contents of ammonia-nitrogen and nitrite-nitrogen poison the prawn’s body, weaken its physique and may induce and worsen the disease.

TIDAL FRONTS AND THEIR INFLUENCE ON PRAWN POSTLARVAE IMMIGRATION IN ALBATROSS BAY, THE GULF OF CARPENTARIA, AUSTRALIA

Studies of dynamics in Albatross Bay, the Gulf of Carpentaria, Australia, show strong tides of which M2is the dominant constituent in the region. Tidal fronts are present and they can be modeled by a 2-Dtidal model. Density currents have also been observed with seasonal variations due to the influence ofwet or dry seasons. This paper reviews the effects of these dynamics on the migration of prawn postlarvae in AlbatrossBay and its estuaries. It is found that through its vertical movement triggered by change of salinity theprawn postlarvae can be transported from the coast to the estuary by tides within 2.8 weeks. Howeverthis horizontal displacement mechanism may be destroyed by the tidal front in Albatross Bay. Densitycurrents may alter prawn postlarvae positions in Albatross Bay on a seasonal scale.

HYDROCHEMICAL STATE OF INTERMEDIATE CULTURE POND FOR CHINESE PRAWN JUVENILES

This study deals with the hydrochemical state and management measures for the intermediate culturepond for Chinese prawn (Penaeus orientalis) juveniles. The test result showed that the intermediate cultureof Chinese prawn juvenile can be advanced to around March 20 in the Shanghai area if they are culturedin ponds in simple greenhouses of plastic knitting cloth.The density of juveniles introduced was about35 million per hectare, survival was up to 55%.

Enterobacteria and Vibrio from Macrobrachium amazonicum prawn farming in Fortaleza,Ceará,Brazil

Objective:To investigate the isolation of enterobacteria associated with Macrobrachium amazonicum(M.amazonicum) farming and evaluate the in vitro antimicrobial susceptibility of Vibrio strains.Methods:Strains were isolated from female M.amazonicum prawns and environmental and hatchery water.Biochemical assays were used to identify bacterial genera and those belonging to the genus Vibrio were submitted to further analyses for species identification,through Vitek 2 automated system and scrotyping.Susceptibility test was performed according to Clinical Laboratory Standards Institute.Results:The following genera of enlerobacteria were recovered:Enterobacter(n=11),Citrobacter(n=10),Proteus(n=2),Serratia(n=2),Kluyvera(n=2),Providencia(n=2),Cedecea(n=1),Escherichia(n=1).Edwardsiella(n=1) and BulliauxeUa(n=1).As for Vibrio,three species were identified:Vibrio cholerae non-O1/non-O139(n=4).Vibrio vulnificus(V.vulnificus)(n=1) and Vibrio mimicus(n=1).Vibrio spp.showed minimum inhibitory concentrations values within the susceptibility range established by Clinical Laboratory Standards Institute for almost all antibiotics,except for V.vulnificus,which presented intermediate profile to ampicillin.Conclusions:Enterobacteria do not seem to be the most important pathogens associated with M.amazonicum farming,whereas the recovery of Vibrio spp.from larviculture,with emphasis on Vibrio cholerae and V.vulnificus,deserves special attention due to their role as potentially zoonotic aquaculture-associated pathogens.Furthermore,the intermediate susceptibility of V.vulnificus to ampicillin reflects the importance of monitoring drug use in prawn farming.

A comparative study on the contents of vitamins in the natural and the cultured prawn

A systematically comparative study on the contents of vitamins in the natural and the cultured prawn, Penaeus chinensis, was made by using High-efficiency Liquid Phase Chromatography in 1989. The results show that the vitamin C (Vc) content in the natural prawn was 8. 19% higher than that of the cultured prawn.As the natural prawn's body length increasing, the Vc content in cephalothorax increased continuously, but after August 10, the Vc content in the cultured prawn fell down rapidly. No significant differences in vitamin B1, B2,B6, nicotinic acid (NAc), nicotinamide (NAm) and folio acid (FAc) were found between the natural and the cultured prawn. Therefore, Vc probably is one of major factors limiting the growth and development of Chinese prawn.

Minicistron from a gene of prawn white spot bacilliform virus(WSBV)and its expression

By the sequencing and analysis of genomic DNA and cDNA of WSBV, it was found that there existed a minicistron in the leading sequence of p204 gene. The minicistron utilized rare codons of genes from prawn and WSBV. The p204 gene could be expressed in Escherichia coli whether a miniciston exited in its leading sequence or not, but the amounts of the expressed products of them were different. The minicistron might be related to the expression of p204 gene.