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用1000ml小水体进行斑节对虾和凡纳对虾各期幼体对卤虫无节幼体摄食量的比较实验，结果表明，二种对虾的卤虫摄食量与卤虫密度有关，在相同密度下，糠虾期凡纳对虾卤虫日摄食量明显高于斑节对虾，而卤虫密度对摄食量的影响凡纳对虾略低于斑节对虾，仔虾期卤虫摄食量差异日渐减小，P5-P6已很接近。 相似文献
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通过对凡纳滨对虾Litopenaeusvannamei雌虾投喂添加或不添加维生素A(VA)、维生素E(VE)的4组实验饲料,并以饲喂活饵组为对照组,研究了维生素A、E对凡纳滨对虾受精率、孵化率和幼体存活率的影响.结果表明,第1(饲料中添加0.002%VE)、2(饲料中添加0.002%VE,0.004%VA)、3组(饲料中添加0.004%VA)凡纳滨对虾的受精率、孵化率、幼体存活率及仔虾应激实验(仔虾入淡水30min,再入海水30min)后的存活率均显著高于第4组(饲料中未添加VA、VE),而且第2组凡纳滨对虾的受精率、孵化率及幼体存活率(Z1-M2)与第1、3组相比有增高的趋势. 相似文献
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在凡纳滨对虾育苗涵状幼体期以不同频次添加溶藻弧菌VZ5株,并在糠虾幼体后搭配添加芽孢杆菌Bz5株,测定育苗过程中水质、水体中弧菌密度变动以及对虾幼体生长和存活状况,研究溶藻弧菌VZ5株在凡纳滨对虾育苗中应用的效果。结果表明,添加溶藻弧菌的3个处理组仔虾期氨氮浓度显著低于对照组;仔虾期幼体干重分别为0．0463±0．0009、0．0420±0．0006、0．0407±0．0009g／尾,显著高于对照组（0．0253±0．0003g／尾）。滏状幼体期每天添加溶藻弧菌的处理组幼体成活率显著高于其他处理组（P〈0．05）。溶藻弧菌VZ5株能够有效降低水体中氨氮的积累和促进对虾幼体生长。 相似文献
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《福建水产》2020,(4)
为研究凡纳滨对虾选育性状,在实验水温25.0～29.3℃、实验时间48 h条件下,本研究对A、B、C、D四个凡纳滨对虾选育群体的自交和杂交不同交配组合子代的仔虾幼体(发育期P_(11)～P_(12),体长6.09～7.54 mm)进行了耐低盐能力的比较实验,以48 h的存活率和体长为指标综合评价不同种源子代仔虾幼体的耐低盐能力。结果显示,当盐度为3时,在17个实验组中,低存活率的6个组(存活率17.69%～57.37%)和高存活率的11个组(存活率68.72%～96.10%)存在显著差异(P0.05);耐低盐能力最强的2个实验组分别是A群种虾和D群种虾的正、反杂交子代,而耐低盐能力最弱的2个实验组分别是D群种虾和C群种虾的自交子代。实验结果表明凡纳滨对虾不同种源、不同交配组合繁育的子代仔虾,其耐低盐能力存在差异,研究结果可为对虾选育研究提供参考。 相似文献
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2013年,河北、天津等地区养殖的凡纳滨对虾(Litopenaeus vannamei)育苗期出现死苗、出苗率低的情况,生产上,仔虾个体大小差异较大,造成了严重损失.本研究采用荧光定量PCR方法(Real-time PCR)对天津大港地区采集的108尾凡纳滨对虾仔虾样品进行单尾病原检测.结果显示,传染性皮下及造血组织坏死病毒(Infectious hypodermal and hematopoietic necrosis virus,IHHNV)和虾肝肠胞虫(Enterocytozoon hepatopenaei,EHP)均有检出.IHHNV阳性检出率100％,每微克对虾组织DNA的病毒拷贝数为103-107,且个体较大的样品(1.2-2.0 cm)携带病毒拷贝数偏高;EHP阳性检出率为49.1％,每微克对虾组织DNA的拷贝数为103-105,且集中于个体较小样品(0.7-1.1 cm).对IHHNV和EHP阳性凡纳滨对虾样品进行生物学体长与病毒载量指数相关性分析,显示IHHNV载量指数与对虾生长速率呈正相关,虾组织IHHNV平均载量达8.51×104 copies/μg DNA,为较高的感染水平;EHP的载量与对虾生长速率呈负相关关系,与较大个体阳性检出率较低相对应,虾组织EHP平均载量达到2.19× 104 copies/μg DNA,为较高的感染水平.由此,该批凡纳滨对虾仔虾患病为IHHNV和EHP的混合感染所致,本研究数据为IHHNV和EHP病原混合感染流行情况及其对养殖育苗期仔虾生长的影响提供科学依据. 相似文献
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《福建水产》2020,(3)
为探索凡纳滨对虾选育技术方法,以A、B、C、D四个凡纳滨对虾选育群体的自交和杂交不同交配组合子代的仔虾幼体,进行耐低温能力的比较实验。实验仔虾发育期为P_(11)～P_(12),体长6.09～7.54 mm,实验水温为13.5～19.0℃,实验时间48 h。统计24、36和48 h的存活率,结合体长因素综合评价不同种源子代各组仔虾幼体的耐低温能力。结果表明,从低温实验24 h开始各组存活率出现显著差异。在实验48 h时,16个交配组合中,4组存活率最高且与A群种虾有关(与D群无关)的交配组合平均存活率为10.35%。而4组存活率最低且与A群种虾无关的组合,其中3组与D群有关的交配组合平均存活率为0%。不同种源子代仔虾幼体耐低温能力存在差异。 相似文献
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Shun Watanabe Jun Aoyama Seishi Hagihara Bunpei Ai Rhodora V. Azanza Katsumi Tsukamoto 《Fisheries Science》2013,79(3):375-383
Anguilla luzonensis and A. huangi were each described in 2009 using eels obtained from northern Luzon Island. We examined the taxonomic status of these two groups of eels using morphological and molecular genetic characters. There were no significant differences in two vertebrae counts between eels of A. luzonensis and A. huangi. Mitochondrial 16S ribosomal RNA and cytochrome b genes sequences were obtained and compared among 28 specimens of A. luzonensis, the holotypes of A. luzonensis and A. huangi, and one specimen of the other 15 anguillid species. The specimens of A. luzonensis exhibited almost identical sequences, including the holotype, with only a few site differences, and the genetic difference between the holotypes of A. luzonensis and A. huangi was within the range of differences of specimens of A. luzonensis. The other anguillid species were genetically very different from A. luzonensis and A. huangi, although A. interioris is a closely related species. It is clear that A. luzonensis and A. huangi are the same species, and according to the principle of priority in zoological nomenclature, A. luzonensis Watanabe, Aoyama, and Tsukamoto, 2009 is the valid species name, and A. huangi Teng, Lin, and Tzeng, 2009 is a junior synonym of A. luzonensis. 相似文献
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Nuhman Usman Bambang Irawan Agoes Soegianto 《Journal of the World Aquaculture Society》2013,44(4):547-556
The purpose of this study was to evaluate the acute toxicity of lead for different life stages of shrimp, Litopenaeus vannamei, and to determine the effect of its sublethal concentrations on osmoregulatory capacity (OC) as well as the possible histological alteration in the gills of juvenile shrimp. The 24‐, 48‐, and 96‐h LC50 values for lead to L. vannamei increased progressively with increasing life stage, from nauplii < zoeae < mysis < postlarvae < juvenile. After 15‐d exposure to 3.25, 6.50, and 9.75 mg Pb/L, the OC values of exposed shrimp were reduced by 39, 73, and 157%, respectively compared to control animals. Compared to controls, the lead concentrations in gill tissues increased significantly by 127,500, 137,500, and 141,000% in shrimps exposed to 3.25, 6.50, and 9.75 mg Pb/L, respectively. After lead exposure, hemocytic congestion in efferent vessels and multiple hyperplasia were observed in gill filaments, resulting in narrowed hemolymphatic lacuna. The histopathological effects increased with increasing Pb concentration. 相似文献
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Charles C. Mischke Matt J. Griffin Terrence E. Greenway David Wise 《Journal of the World Aquaculture Society》2013,44(2):288-292
Mosquitofish, Gambusia sp., have been spread throughout the world to biologically control mosquitoes. However, the fish has gained a reputation as an invasive species and has been implicated in displacing native aquatic species. Gambusia affinis are native to the southeastern United States and commonly occur in commercial channel catfish, Ictalurus punctatus, production ponds. We investigated effects of mosquitofish presence on zooplankton populations, water quality, disease occurrence, and fish production in experimental ponds. There were no differences between ponds with or without mosquitofish in numbers of calanoid copepods, cyclopoid copepods, total copepods, Bosmina sp., Ceriodaphnia sp., Moina sp., Daphnia sp., or total cladocerans. There were also no differences in copepod and cladoceran sizes. Copepod nauplii were more numerous during the summer months in ponds with mosquitofish. There were no differences in water quality variables (soluble reactive phosphorus, nitrate, nitrite, ammonia, total nitrogen, total phosphorus, pH) or phytoplankton density between ponds stocked with and without mosquitofish. Catfish production and disease occurrence were also similar between ponds with and without mosquitofish. Although mosquitofish may cause problems when stocked outside their native range, there does not appear to be any adverse effects of mosquitofish presence in catfish production ponds. 相似文献
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Mulloway (Argyrosomus japonicus) occur in estuarine and coastal waters surrounding Australia, Africa, India, Pakistan, China, Korea and Japan, where they are important in fisheries. This study identified that mulloway in south-eastern Australia had similar growth rates, but matured at smaller lengths and younger ages, to those in South Africa and Western Australia. Growth of both sexes was similar to about 5 years, after which females grew faster and attained a greater maximum length than males. Female mulloway matured at 4–5 years of age with a L50 of 68 cm, whereas males matured at 2–3 years of age with a L50 of 51 cm. The commercial fishery in New South Wales was characterised by declining catches and a reduction in the proportion of mulloway of mature lengths in landings. During 2002–2005 commercial landings were dominated (83%) by fish within 15 cm of the current minimum legal total length of 45 cm and aged 2 and 3 years (>80%), even though mulloway can attain lengths of 200 cm and live >30 years. Estimates of the rates of instantaneous total mortality ranged between 0.34 and 0.45, whilst the rate of instantaneous natural mortality (M) was estimated to be approximately 0.12. Yield-per-recruit analyses indicated that mulloway in New South Wales are being growth overfished and substantial increases in yield could be achieved by increasing the length at first harvest. Values of the spawning potential ratio were below 0.2 under a range of mortality estimates, suggesting that mulloway are at risk of recruitment overfishing. These results suggest that the spawning stock of mulloway in south-eastern Australia has been depleted and that remedial management action is required to protect this iconic species. 相似文献
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The effects of exposing the eggs of Pacific threadfin and amberjack eggs (AEs) to different concentrations of hydrogen peroxide for 5 min on hatch rate and survival were assessed in a series of experiments using a petri dish model rearing system. Despite significant inter‐batch variation in hatch rate, it was shown that eggs of both species could be safely exposed to up to 11 340 mg L−1 H2O2 for 5 min. Exposure to 34 230 mg L−1 H2O2 for 5 min was shown to be lethal to AEs at a late stage of development. In two further experiments, it was demonstrated that Pacific threadfin eggs were resistant to all tested concentrations of a range of polyvinylpyrrolidone iodine (PVP‐I) concentrations and contact times (up to 1000 mg L−1 PVP‐I for 10 min). The level of bacteria adhering to the eggs of both species was highly variable. Where eggs were heavily colonized (>104 cfu egg−1), hydrogen peroxide concentrations of at least 11 340 mg L−1, or PVP‐I concentrations higher than 500 mg L−1 for 10 min, were required for effective sterilization. In less colonized batches, rinsing in sterile seawater or exposure to lower (550 mg L−1) concentrations of H2O2 was sufficient to result in high apparent levels of surface sterility (<1 cfu egg−1). 相似文献
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《水生生物资源》1999,12(4):239-246
The effect of different parameters on short-term storage capacity of turbot ova was assessed over a 45-h period after ova collection for fertilization rates and over a 9-h period after ova collection for hatching rates. Increasing the volume of ova sampling from 0.5 to 2.5 mL, as well as adding an antibiotic–antimicotic solution or oxygen did not significantly change the storage capacity of ova. Regarding the hatching rates, a higher storage ability was recorded at 8 and 13 °C, compared to 3 °C. The mean composition of the ovarian fluid was determined (n = 57 spawns). Use of a diluent mimicking the ovarian fluid significantly decreased the storage ability as assessed by the fertilization rates but did not modify the hatching rates. Diluting ova in an artificial ovarian fluid deprived of calcium significantly decreased the fertilization and hatching rates during the storage period. Furthermore, addition or not of soybean trypsin inhibitor (Sigma T 9003) to the artificial ovarian fluid deprived of calcium did not significantly change the results. Storage capacity of control batches of ova was low: at 13 °C, without any diluent and when ova were fertilized 3 h after stripping, the hatching rate was lowered to 62.4 ± 29.4 % (mean ± SD) of the initial value. 相似文献
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Effects of Dietary Savory and Myrtle Essential Oils on Growth,Survival, Nutritional Indices,Serum Biochemistry,and Hematology of Farmed Rainbow Trout,Oncorhynchus mykiss,Fry 
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下载免费PDF全文 Mohsen Mohamadi Saei Kiarash Beiranvand Mohammad K. Khalesi Farzaneh Mehrabi 《Journal of the World Aquaculture Society》2016,47(6):779-785
The effects of diets containing different levels of essential oils from savory Satureja khuzestanica Jamzad and myrtle Myrtus communis L and an immunity complement were investigated on growth, survival, nutritional indices, serum biochemistry, and hematology of farmed rainbow trout, Oncorhynchus mykiss, fry (n = 4500; 5 ± 2 g). The essential oils were dosed as 300 and 500 mg/kg diet. After 60 d, the fish fed 300 mg/kg of the essential oils showed the highest counts of white blood cells (P < 0.05). The same treatment revealed the greatest levels of hematocrit, total protein, and albumin, but glucose and cholesterol values significantly decreased compared with the control (P < 0.05). Feeding fish with 300 mg/kg of the essential oils led to highest records of specific growth rate and survival rate but the lowest feed conversion ratio (FCR), and those fed with immunity complement attained the lowest values of growth parameters. The fry fed with immunity complement and 300 mg/kg of myrtle essential oil achieved the highest and lowest FCR values, respectively. The results indicate that dietary supplementation of 300 mg/kg of the above essential oils exert positive impacts on the growth performance, feeding efficiency, and hematological factors in O. mykiss. 相似文献
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Rebecca Lochmann Ruguang Chen Fred W. Chu‐Koo William N. Camargo Christopher C. Kohler Craig Kasper 《Journal of the World Aquaculture Society》2009,40(1):33-44
To facilitate economical culture of black pacu, Colossoma macropomum, and red pacu, Piaractus brachypomus, in the Amazon region of South America, we assessed locally available alternative energy sources for practical diets. We tested the effects of control diets (containing wheat products) versus diets with different Amazonian feedstuffs (yucca, Manihot sculenta, plantain, Musa paradisiaca, or pijuayo, Bactris gasipaes) on the performance of the pacus in three feeding trials. Black pacu (22.5 ± 0.03 g; Trial 1) or red pacu (2.56 ± 0.01 g; Trial 2) were fed diets containing 30% wheat bran (control) or cooked or uncooked yucca, plantain, or pijuayo for 12 wk. In Trial 3, larger black pacu (86.9 ± 6.4 g) were grown to market size in 24 wk on similar diets. Weight gain, feed conversion, survival, alternative complement activity, and lysozyme were similar among diets. Hepatosomatic index, liver glycogen, and dry matter were affected by diet in Trials 1 and 2, but effects were not consistent among trials. In Trial 3, protein efficiency ratio was lower in fish fed the diet containing wheat middlings. However, relative to wheat bran or wheat middlings, all feedstuffs tested were effective energy sources for juvenile black pacu and red pacu. 相似文献
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Sperm Motilities in Waigieu Seaperch,Psammoperca waigiensis: Effects of Various Dilutions,pH, Temperature,Osmolality, and Cations 下载免费PDF全文
下载免费PDF全文 The objectives of this study were to evaluate the effects of varying dilutions, pH, temperature, osmolality, and cations on sperm motility parameters in waigieu seaperch, Psammoperca waigiensis. The maximum velocity of average in path (VAP), percentage of motile cells (MOT), and duration of sperm motility (DSM) were observed when semen was diluted in artificial seawater (ASW) at a ratio of 1:100 (144.9 ± 0.6 µm/sec, 95.6 ± 0.4%, and 230.3 ± 2.3 sec, respectively), at 30 C (142.0 ± 0.6 µm/sec, 93.6 ± 0.4%, and 238.3 ± 0.9 sec, respectively), and pH 8 (144.8 ± 0.6 µm/sec, 93.3 ± 0.4%, and 234.0 ± 1.5 sec, respectively). Maximum VAP, MOT, and DSM were obtained in each solution containing 0.6 M NaCl (143.8 ± 1.0 µm/sec, 91.3 ± 2.0%, and 230.6 ± 4.2 sec, respectively), 0.6 M KCl (135.1 ± 3.1 µm/sec, 91.1 ± 3.1%, and 230.3 ± 3.7sec, respectively), 0.2M CaCl2 (105.3 ± 4.7μm/sec, 47.9 ± 2.7%, and 120.7 ± 1.3 sec, respectively), 0.2 M MgCl2 (107.3 ± 3.0 m/s, 42.1 ± 3.3%, and 120.3 ± 4.8 sec, respectively), and osmolality of 400 mOsm/kg (145.1 ± 2.5 µm/sec, 93.0 ± 2.1%, and 346.5 ± 4.4s, respectively). We used these mediums as artificial insemination media for fertilizing matured eggs. The results showed that the fertilization and hatching rates in 0.6 M NaCl (75.3 ± 0.6% and 57.0 ± 2.4%, respectively), ASW (70.8 ± 1.2% and 51.2 ± 1.8%, respectively), or 400 mOsm/kg (72.9 ± 1.8% and 55.3 ± 1.6%, respectively) were higher than that in seawater (63.9 ± 1.2% and 39.2 ± 3.9%, respectively). In conclusion, using 0.6 M NaCl, ASW, or 400 mOsm/kg as an artificial insemination medium is effective for fertilizing of waigieu seaperch. 相似文献