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丹江口库区入库河口土壤养分的空间变异研究——以青塘河河口为例 总被引：1，自引：0，他引：1
《水生态学杂志》2016,(3)
通过探究河口土壤养分状况及空间变化规律,为入库河口生态修复提供理论依据,以丹江口水库青塘河入库河口为例,采用传统描述性统计和地统计分析法,对入库河口表层土壤养分空间变异特征进行了研究。结果表明,土壤各养分指标变异系数为38.6%~97.9%,除速效磷外,总体属中等强度变异。研究区土壤各养分指标均具有中等程度的空间自相关性,自相关距离为272~2 110 m,由大到小依次为:速效磷碱解氮有机质速效钾。研究区土壤有机质含量为7.97~45.03 g/kg,处于中等偏上水平,碱解氮含量为42.97~178.70 mg/kg,处于中等偏下水平,速效磷含量为5.03~121.40 mg/kg,速效钾含量为62.50~820.65 mg/kg,分别达到丰富和极丰富水平。受土壤母质、地形、气候等非人为因素和施肥、作物、管理水平等人为因素影响,研究区有机质、速效磷和碱解氮均呈现出由东南向西向北方向逐渐递减的趋势,速效钾在中部偏东处含量最高。与传统统计方法相比,地统计分析能较好地反映土壤养分含量的结构性、随机性、独立性和相关性。研究结果可为丹江口水库青塘河入库河口植被恢复与生态修复提供理论依据。 相似文献
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通过探究河口土壤养分状况及空间变化规律,为入库河口生态修复提供理论依据,以丹江口水库青塘河入库河口为例,采用传统描述性统计和地统计分析法对入库河口表层土壤养分空间变异特征进行了研究。结果表明,土壤各养分指标变异系数为38.6%~97.9%,除速效磷外,总体属中等强度变异。研究区土壤各养分指标均具有中等程度的空间自相关性,自相关距离为272～2110 m,由大到小依次为：速效磷>碱解氮>有机质>速效钾。研究区土壤有机质含量为7.97～45.03 g/kg,处于中等偏上水平,碱解氮含量为42.97～178.70 mg/kg,处于中等偏下水平,速效磷含量为5.03～121.40 mg/kg,速效钾含量为62.50～820.65 mg/kg,分别达到丰富和极丰富水平。受土壤母质、地形、气候等非人为因素和施肥、作物、管理水平等人为因素影响,研究区有机质、速效磷和碱解氮均呈现出由东南向西向北方向逐渐递减的趋势,速效钾在中部偏东处含量最高。与传统统计方法相比,地统计分析能较好地反映土壤养分含量的结构性、随机性、独立性和相关性。研究结果可为丹江口水库青塘河入库河口植被恢复与生态修复提供理论依据。 相似文献
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为了解滨海潮间带盐沼湿地翅碱蓬生长的土壤环境,2013年7月～8月采集辽宁盘锦、辽宁庄河、天津、山东东营及江苏连云港5个不同纬度典型滨海翅碱蓬生长区域土壤,研究了其理化特征。结果表明,翅碱蓬可生长的我国滨海潮间带湿地土壤含盐量（2.5±0.5）g/kg～（19.0±6.1）g/kg、氯离子含量（1.16±0.04）g/kg～（11.27±0.3.43）g/kg、pH （7.05±0.01）～（8.96±0.01）、碱度（3.56±0.59）mmol/kg～（8.78±0.78）mmol/kg、全碳含量（7.70±1.84）mg/kg～（21.73±4.11）mg/kg,全氮含量（0.36±0.03）mg/kg～（0.87±0.04）mg/kg、无机氮含量（1.95±0.95）mg/kg～（16.10±1.57）mg/kg、速效磷含量（5.26±0.33）mg/kg～（39.98±0.61）mg/kg、速效钾含量（0.53±0.19）mg/kg～（1.77±0.01）mg/kg,其中铵氮含量（1.60±0.58）mg/kg～（8.76±0.16）mg/kg、亚硝酸盐氮含量（0.01±0.00）mg/kg～（0.11±0.00）mg/kg、硝酸盐氮含量（1.00±0.20）mg/kg～（2.54±1.09）mg/kg。土壤N:P比平均值为0.80±0.25、N:K比平均值为17.77±6.08、P:K比平均值为26.90±4.67;TC:TN比平均值为26.50±4.67。在符合这些土壤特征的滨海潮间带光滩可采用翅碱蓬进行生态修复。 相似文献
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水文节律是河岸带植物群落演替的主要驱动因子,受水文节律影响的土壤理化特性也有可能逐渐改变周边植被,为了探究周期性淹没对三峡水库消落带植物群落及其生境状况的影响,2015年8-9月,以三峡水库腹地万州段消落带为研究区域,调查分析了8个样地、24个样带、96个样方的消落带植被及土壤理化特征。结果表明,在三峡库区万州段消落带共调查到维管植物22科、47属、51种,其中禾本科、菊科、蓼科和莎草科的种类数较多;植物群落组成以草本植物为主,一年生和多年生草本植物分别占58.8%和27.5%。高程不同,群落优势种有差异,145~155 m及156~165 m区域优势度较高的物种相近,为狗牙根(Cynodon dactylon)、光头稗(Echinochloa crusgalli var.mitis)和醴肠(Eclipta prostrata);高程166~175 m区域优势度较高的物种为鬼针草(Bidens pilosa)和狗尾草(Setaria viridis)和狗牙根;高程156~166 m区域植物鲜重均值最高,为(2199.1±863.9)g/m2;高程166~175 m区域Shannon-Wiener多样性指数和Pielou均匀度指数的均值最高,分别为(2.00±0.30)和(0.85±0.06)。随着坡度等级增加,植物鲜重和盖度呈递减趋势,物种数在坡度6~15°区域最高。长江左岸消落带植物鲜重、高度、Shannon-Wiener和Pielou指数高于右岸。消落带土壤理化性质具有较高的空间异质性,土壤容重、p H、有机质、全氮、有效氮、全磷、有效磷均值分别为(1.34±0.09)g/cm3、(7.60±0.47)、(6.02±2.94)g/kg、(1.21±0.16)g/kg、(53.42±9.67)mg/kg、(0.42±0.14)g/kg、(6.55±2.82)mg/kg,其中有机质的变异系数最大,其次为有效磷和全磷。左岸消落带土壤p H、有机质、全氮和有效氮含量均值低于右岸,但左岸土壤全磷和有效磷含量高于右岸。淹没时间和土壤有效磷含量对消落带植物重要值影响较大。 相似文献
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在26~30℃和盐度18~22下,研究了每千克干等氮等能基础饲料中添加0、4、8、16、32mg和64mg蛋氨酸铜的饲料(铜实际含量为2.7、7.5、11.2、19.8、30.4mg/kg和52.1mg/kg)对体质量(18.46±0.11)mg方格星虫稚虫的质量日增加、组织铜含量和消化酶活性的影响。基础饲料以酪蛋白、明胶为蛋白源,糊精为糖源,鱼油为脂肪源,含粗蛋白44.25%,粗脂肪9.23%,灰分9.64%,能值为19.71 MJ/kg。56d的饲养结果表明,饲料铜水平显著影响方格星虫稚虫的质量日增加、体壁铜含量、虫体铜含量(P0.05)。稚星虫的质量日增加随饲料铜水平的增加呈先增后降趋势,随后趋于平稳。饲料铜水平为7.5、11.2、52.1mg/kg时,稚虫的质量日增加差异不显著;当饲料铜含量为11.2mg/kg时,稚星虫质量日增加达最大值(0.68±0.04)mg/d。稚星虫的体壁铜含量和虫体铜含量均随着饲料中铜含量的提高而显著升高,当饲料铜含量为52.1mg/kg时,达到最大值。各处理组稚星虫体腔液铜含量为2.32~4.53μg/g,与消化酶活性一致,组间差异不显著(P0.05)。综合质量日增加和饲料成本考虑,建议方格星虫稚虫饲料铜水平的添加量为7.5~11.2mg/kg。 相似文献
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《水产学杂志》2017,(6)
2012年夏季(8月)利用QNC6-1型挖泥斗采样,监测山东滨州浅海11个站位表层沉积物中Zn、Cr、Cd、Cu、Pb、Hg和As 7种重金属的含量,应用Hakanson潜在生态危害指数法评价沉积物中重金属的污染现状和潜在生态风险。结果表明:调查区域沉积物中Zn、Cr、Cd、Cu、Pb、Hg和As的含量范围分别为19.80-63.70mg/kg、27.90~38.70mg/kg、0.138~0.192mg/kg、23.10~29.50mg/kg、8.75~17.20mg/kg、0.0221~0.0384mg/kg,和8.29~10.70mg/kg,平均含量分别为(52.15±12.03)mg/kg、(32.83±3.14)mg/kg、(0.16±0.02)mg/kg、(26.50±2.11)mg/kg、(13.94±2.87)mg/kg、(0.03±0.01)mg/kg和(8.90±0.66)mg/kg;沉积物中主要潜在重金属污染因子是Cd和Cu,重金属影响因子的顺序由强至弱依次为:CdCuPbZnAsCrHg;重金属综合污染指数表明,该海域环境质量总体以低污染为主;各种重金属的潜在生态危害系数由大至小依次为:CdAsCuHgPbCrZn,Cd为潜在生态风险因子;潜在生态风险指数平均值为(57.36±4.14),属于低潜在生态风险,表明目前滨州浅海沉积物中重金属潜在生态风险水平较低。 相似文献
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河南中牟县万滩镇养殖池塘底泥重金属污染评价 总被引：1，自引：0，他引：1
调查了河南中牟县万滩镇养殖池塘底泥中Cr、Cu、Zn、Pb、Cd和Hg等重金属元素的分布特征,并以内梅罗综合污染指数评价法对其污染状况进行评价。结果表明,该地区首要污染重金属Cr平均含量高达53.35mg/kg,超无公害水产品产地环境要求国家标准最高限量幅度为6.7%;Cd含量在0.07~1.13 mg/kg之间,其平均值0.45 mg/kg未超过无公害水产品产地环境要求,但超出《土壤环境质量标准》Ⅰ类;Cu、Zn、Pb、Hg含量范围分别7.98~40.31 mg/kg、30.24~80.22 mg/kg、11.29~24.50 mg/kg、0.08~0.17 mg/kg,平均值均未超过2项国家标准最高限值;以《农产品安全质量无公害水产品产地环境要求》为评价标准,利用内梅罗综合污染指数法评价重金属综合污染指数表明,该地区的污染状态主要为警戒级和轻微污染级。 相似文献
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2012年9月和2013年9月对汉丰湖湿地5个断面的生境和植物群落特征进行了调查,分析了三峡水库运行对汉丰湖湿地植物群落及土壤生境的影响。结果表明,维管束植物共计59种,隶属于26科、20属,其中菊科、禾本科和蓼科种类较多;群落结构以草本植物为主,其中一年生草本植物占54.2%,多年生草本植物占37.3%;植物群落鲜重、高度和盖度平均值(范围)依次为2 031.5(488.3~6 586.1)g/m2、59.2(19.6~102.2)cm、109%(23%~201%);土壤容重、pH、有机质、有效氮、有效磷和有效钾的平均值(范围)分别1.32(1.00~1.60)g/cm3、8.15(6.83~8.59)、10.03(1.40~22.5)g/kg、29.37(6.00~94.38)mg/kg、12.18(1.33~59.37)mg/kg和46.13(2.50~219.00)mg/kg;重要值较大的有狗牙根(22.84±5.78)、牛鞭草(16.38±13.27)、马唐(11.10±12.27)、无芒稗(10.83±3.64)和狗尾草(9.56±5.38);主要环境影响因子为土壤pH值和有效钾含量。 相似文献
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2016年7月至2017年5月对乌伦古湖12个采样点(4个湖区)的水质进行了监测,分析了不同湖区的水质特征,并对比历史资料探究水质变化及成因。结果显示,乌伦古湖2016-2017年度年均矿化度为1.64 g/L、p H为8.70、透明度为1.90 m、水深为8.78 m、溶解氧为7.55 mg/L,总氮1.06 mg/L,总磷0.03 mg/L。与2006-2008年相比,年均矿化度由2.31 g/L降低到1.64 g/L,各湖区矿化度含量均降低,其中靠近额尔齐斯河引水的小海子(由1.97 g/L降至0.82 g/L)和接受吉力湖来水的中海子(由2.41 g/L降至1.60 g/L)矿化度降低最为明显;年均总氮含量由0.86 mg/L增加到1.06 mg/L,年均总磷含量稳定在0.03 mg/L左右,各湖区总氮、总磷含量除小海子降低外(总氮由0.83 mg/L降至0.72 mg/L;总磷由0.03 mg/L降至0.01 mg/L),其他各湖区含量保持稳定或升高,其中中海子升高最为明显(总氮由0.94 mg/L升至1.43 mg/L;总磷由0.03 mg/L升至0.05 mg/L)。研究表明,额尔齐斯河引水对于乌伦古湖水体矿化度、总氮及总磷均有稀释作用,吉力湖来水虽然对乌伦古湖水体矿化度也有稀释作用,但同时提高了总氮和总磷含量。 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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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 
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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
16.
The endemic, anadromous cyprinidChalcalburnus tarichi is the only fish species known to occur in alkaline Lake Van (Eastern Anatolia, Turkey). EightC. tarichi were maintained individually in Lake Van water (17 – 19°C; pH 9.8; 153 mEq·I–1 total alkalinity; 22 total salinity) and tank water samples analyzed for 24 h in 2 to 4 h intervals. At zero time, < 1µM ammonia was present and urea was undetectable in the tank water; at 24 h, total ammonia and urea made up 114±32 and 35±25µM, respectively. Over the experimental period, ammonia-N and urea-N excretion averaged 1041±494 and 607±169moles·kg–1 fish·h–1, respectively. The extent of urea excretion was highly variable between specimens. Uric acid excretion was not detectable.Urea was present at high concentrations in all tissues and plasma (25 – 35moles·g–1·ml–1) of freshly caughtC. tarichi; total ammonia content of the tissues was by a factor of 1.9 (liver) to 3.0 (brain) lower. High arginase activity (2.4±0.2 U·min–1·g–1) was detected in the liver ofC. tarichi but ornithine carbamoylphosphate transferase, a key enzyme of the ornithine-urea-cycle, was absent. Ureagenesis is likely through degradation of arginine and/or uricolysis. High glutamine synthetase activity (11±0.6 U·min–1·g–1) and low ammonia content in brain suggest that, like other teleosts,C. tarichi has an efficient ammonia detoxification in the brain, but in no other tissue.Nitrogenous waste excretion at alkaline pH is discussed. The ability ofC. tarichi to excrete high levels of ammonia at extremely alkaline pH is unique among teleosts studied so far. The mechanism of ammonia excretion under Lake Van conditions remains to be elucidated. 相似文献
17.
There has been growing concern about the overuse of antibiotics in the ornamental fish industry and its possible effect on the increasing drug resistance in both commensal and pathogenic organisms in these fish. The aim of this study was to carry out an assessment of the diversity of bacteria, including pathogens, in ornamental fish species imported into North America and to assess their antibiotic resistance. Kidney samples were collected from 32 freshwater ornamental fish of various species, which arrived to an importing facility in Portland, Oregon from Colombia, Singapore and Florida. Sixty‐four unique bacterial colonies were isolated and identified by PCR using bacterial 16S primers and DNA sequencing. Multiple isolates were identified as bacteria with potential to cause disease in both fish and humans. The antibiotic resistance profile of each isolate was performed for nine different antibiotics. Among them, cefotaxime (16% resistance among isolates) was the antibiotic associated with more activity, while the least active was tetracycline (77% resistant). Knowing information about the diversity of bacteria in imported ornamental fish, as well as the resistance profiles for the bacteria will be useful in more effectively treating clinical infected fish, and also potential zoonoses in the future. 相似文献
18.
Effect of iodophor disinfection of non‐hardened Salmo trutta eggs on their bacterial and fungus load 下载免费PDF全文
下载免费PDF全文 Franz Lahnsteiner 《Aquaculture Research》2017,48(7):3901-3909
This study investigated the efficiency of iodophor disinfection (135 ppm active iodine for 15–30 min) of non‐hardened Salmo trutta eggs against different groups of bacteria and against fungus. Egg samples were taken from non‐disinfected and from disinfected eggs, microorganisms were cultured on specific nutrient media and their mass was measured by turbidimetric methods. Bacteria and fungus mass of non‐hardened eggs could be reduced but not eliminated by iodophor disinfection with 135 ppm active iodine for 15 min. The extent of reduction was 47–65% (Experiment 1). The efficiency of disinfection increased with disinfection time as the reduction in bacteria and fungus mass was 40–55% after 15 min and 58–74% after 30 min (Experiment 2). Disinfection efficiency of iodophor solution diluted in water (reduction 49–57%) and of iodophor solution diluted in sodium chloride solution iso‐osmolar to the oocytes (reduction 52–61%) was similar (Experiment 3). The reduction in bacteria and fungus mass was persistent as it was 39–72% lower in embryos deriving from disinfected eggs than in embryos deriving from non‐disinfected ones (Experiment 4). In conclusion, the tested disinfection method is inadequate to eliminate pathogens completely but it could positively influence immune defence of eggs and embryos. 相似文献
19.
T. Citarasu K. Venkatramalingam M. Micheal Babu R. Raja Jeya Sekar M. Petermarian 《Aquaculture International》2003,11(6):581-595
The indiscriminate use of antibiotics and chemicals in shrimp hatcheries has led to biomagnification and that in turn could
lead to rejection of a whole consignment. The application of the bioencapsulation technique as a tool for curative treatment
in shrimp larvae was investigated. Herbs having antibacterial properties such as Solanum trilobatum, Andrographis paniculata and Psoralea corylifolia (methanolic extracts) were bioencapsulated in Artemia and fed to Penaeus monodon post larvae PL 1–25. The post larvae were reared in a medium inoculated with pathogenic bacteria such as Pseudomonas aeruginosa, Staphylococcus aureus, Salmonella typhi and Vibrio sp. Post larvae reared in the non-inoculated water and fed with non-enriched Artemia exhibited 90% survival, highest specific growth rate (12.43%) and reduced bacterial load. P. monodon reared in the bacterial inoculated water and fed with the non-enriched Artemia exhibited the lowest survival (10–30%), specific growth rate (8.42–9.1%) and increased bacterial load (2.86 × 103 to 3.76 × 105 cfu/g). The methanolic extracts of the herbs helped to increase survival and specific growth rate and reduced bacterial load
in the P. monodon culture system. Among the three herbal extracts, P. corylifolia enriched Artemia fed post larvae showed the tendency to higher survival (>50%), growth rate (11.5 averaged) and low bacterial load (1.12 × 105 cfu/g).
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献