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1.
【目的】构建刺参（Apostichopus japonicus）高效清洁的循环水养殖系统,并探究不同料泥质量比对刺参生长的影响,为刺参工厂化循环水养殖提供新的工艺实验数据。【方法】通过测定养殖水体中的亚硝氮和氨氮浓度、刺参生长指标、肠道消化酶活性指标等的变化,分析确定刺参循环水养殖系统中饵料适宜的料泥质量比。【结果与结论】在120 d的养殖过程中,所构建的循环水养殖系统自清洁效果明显,养殖水质良好,NH4+-N（≤0.289 mg/L）与NO2--N（≤0.025 mg/L）质量浓度均在适合刺参生长的安全浓度范围内,刺参的平均增重率达43.70%。实验初期,随饲料中料泥质量比增加,刺参生长速率降低,但60 d后,料泥质量比1∶3和1∶2的实验组刺参保持快速生长,而料泥质量比1∶4和1∶1的刺参生长相对缓慢。实验结束时,料泥质量比1∶3和1∶2组的刺参肠道淀粉酶、脂肪酶、胰蛋白酶活力均显著高于其他两组（P <0.05）。因此,刺参工厂化循环水养殖具有可行性,且最优料泥质量比为1∶3,此时刺参肠道内的消化酶活性较高、生长速率最快。  相似文献   

2.
波吉卵囊藻的固定化培养及利用   总被引：3，自引：0，他引：3  
以褐藻酸钙为固定化载体,探讨了胶球直径、不同接种量、CaCl2溶液浓度、褐藻酸钠浓度等条件对波吉卵囊藻(Oocystisborgei)固定化培养及对养殖水体水质的影响。结果表明:波吉卵囊藻固定化培养的最好条件是微藻接种量为1×106 mL-1,CaCl2溶液的质量浓度为30g/L,褐藻酸钠溶液的质量浓度为20g/L。在此条件下制备的固定化藻珠,波吉卵囊藻的生物量从1 83×10-2 mg/粒增加到17. 46×10-2 mg/粒,增加了近10倍,生长率相对较高,证明了它的生理活性不会因固定化而受干扰。引入固定化的波吉卵囊藻不但可以降低养殖水体中氨氮、亚硝酸氮等有害因子的浓度,还能提高水中溶解氧含量,使水体环境长时间处于良好的动态平衡状态。  相似文献   

3.
【目的】研究养鱼池、微滤机、臭氧-蛋白质分离器、生化过滤器组成的循环水系统对杂交石斑鱼的养殖效果。【方法】利用低密度(200尾/池)珍珠龙趸养殖的自然微生物对循环水系统进行生物挂膜30 d,使用循环水养殖系统养殖体质量(270.5±4.5)g的杂交石斑鱼[Epinephelus fuscoguttatus (♀)×Epinephelus lanceolatus (♂)](下称"珍珠龙趸")60 d,放养密度2 000尾/池,以相同放养量相同养殖池的流水养殖系统作对照。监测循环水养殖系统的挂膜效果,测定循环水养殖系统和流水养殖系统的氨氮、亚硝酸盐、硝酸盐、化学需氧量、悬浮固体粒子等指标,测定珍珠龙趸的生长状况。【结果】循环水养殖系统生化过滤器内部滤料出现附着菌膜,水质变化趋于稳定,挂膜状况良好,养殖期系统出水氨氮、亚硝酸盐、化学需氧量、固体粒子质量浓度均显著低于流水养殖池(P 0.05),去除率分别为65.93%、48.51%、39.92%、80.61%;经60 d养殖,循环水养殖珍珠龙趸存活率89.25%,养殖密度达35.10 kg/m3,体质量(491.7±16)g,增重率62.23%,特定生长率0.82%,饲料系数1.16,而流水养殖珍珠龙趸存活率88.15%,养殖密度为32.16 kg/m3,体质量(446.4±19) g,增重率48.48%,特定生长率0.71%,饲料系数1.27。【结论】循环水养殖系统水处理效果显著,珍珠龙趸养殖效果良好。  相似文献   

4.
正为全面落实自然资源"两统一"职责,提升自然资源治理体系和治理能力现代化水平,按照"放管服"改革工作要求,河南省自然资源厅积极探索实践,努力以遥感动态监测进一步提升服务自然资源监测监管能力和效率。遥感动态监测是从不同时间或在不同条件下获取的同一地区的遥感影像中,识别和量化地表类型的变化、空间分布状况和变化量,遥感动态监测过程一般可分为三个步骤,即数据  相似文献   

5.
在室内水泥池,利用沙层自净养殖模式和直接铺沙养殖模式对不同规格的方斑东风螺(Babylonia areolataLink)进行了高密度养殖的研究。结果表明,沙层自净养殖模式养殖小螺、中螺、大螺组日均增重分别为0.031、0.088、0.098 g/d,沙层NH4+-N最高含量w分别为1.3、2.1、3.1 mg/L,H2S最高含量w分别为0.03、0.07、0.14mg/L,各规格组东风螺保持正常生长和活动,成活率92.9%以上;直接铺沙养殖模式养殖小螺、中螺、大螺日均增重分别为:0.023、0.051、0.068 g/d,成活率分别为95.2%、86.7%、84.9%,沙层NH4+-N最高含量w达到13.7mg/L,H2S最高含量w达到0.47 mg/L,沙层底质恶化,东风螺活动异常、不摄食。可见,沙层自净养殖模式对方斑东风螺的生长、成活率、沙层水质控制效果显著,在一定程度上克服了直接铺沙养殖底质恶化问题。  相似文献   

6.
采用复相乳液法,以乙基纤维素为包囊材料,明胶溶液为保护液制取微胶囊,对副溶血弧菌噬菌体(Vibrio parahaemolyticus phage)进行固定化,制备噬菌体微胶囊。结果显示,乙基纤维素质量浓度为30 g/L,明胶质量浓度为20 g/L,搅拌速度为600 r/min,时间30 min,副溶血弧菌噬菌体悬液与乙基纤维素溶液的体积比为1∶3时,所得微胶囊有较好的噬菌体缓释性能,综合评价指数最高。对方斑东风螺(Babylonia areolata)饲以混有噬菌体微胶囊的饵料,当饵料中噬菌体微胶囊质量分数为1.0 g/kg时,与对照组比较,东风螺肠道宿主菌平均减少96%,水体中宿主菌减少72%,差异均有统计学意义(P0.05);以黏附剂按1.5 g/kg的剂量将噬菌体微胶囊黏附于对虾饵料,并投喂凡纳滨对虾(Litopenaeus vannamei),对虾肠道的宿主菌比对照组平均减少86%,水体中宿主菌比对照组减少68%,差异均有统计学意义(P0.05)。微胶囊可有效控制宿主弧菌的在养殖体系的浓度,减少养殖动物弧菌病的产生。  相似文献   

7.
为了解九孔鲍养殖环境中细菌生理菌群的生态作用,对分离自养殖水体的33株菌株的产酶能力和种类进行了研究。结果表明,具有分泌胞外蛋白酶、脂肪酶和纤维素酶能力的菌株分别为39.4%、57.6%和30.3%;在这33株菌中,产至少一种胞外酶的菌株比例高达63.6%。API鉴定结果表明,在有能力分泌胞外蛋白酶、脂肪酶和纤维素酶的菌株中,弧菌菌群所占的比例分别为46%、42%和40%,而其中河流弧菌又占各弧菌菌群比例的83.3%、62.5%和100%。充分阐明弧菌,尤其是河流弧菌为优势菌,在鲍鱼养殖微生物态中起的重要作用。  相似文献   

8.
分析一种较低脂肪、以海水动物蛋白原料为主的饲料的营养成分,以之饲喂方斑东风螺(Babyloniaareolata)154 d,研究该饲料对方斑东风螺的养殖效果。结果表明,饲料营养成分(干物质)质量分数为氨基酸41.8%,总糖24.7%,多糖9.43%,粗脂肪4.8%。用此饲料养殖方斑东风螺,增重速率0.18±0.06 g/d,壳增长速率200±0.70μm/d,生长速率比用鲜鱼鱼肉饲料的对照组略快,但没有显著差别(p>0.05);养成螺(干物质)氨基酸质量分数为68.8%,总糖为12.52%,多糖为2.60%,单糖成分以葡萄糖和甘露糖为主,粗脂肪质量分数为2.74%。所养殖螺继续用该配合饲料养殖,次年通过营养加强后作为亲螺,产卵量1.8±0.6万粒,卵的孵化率96%,比用鲜鱼鱼肉饲料的对照组均有显著提高(0.01相似文献   

9.
以固体潮汐包络为标准对云龙台同点记录数据进行统一量化,利用量化数据计算振幅谱,并根据振幅随频率的变化评判不同记录数据对长周期慢变信号的响应,分析洞体应变、水管倾斜仪低频段记录数据的差异。结果表明,对于周期大于固体潮汐的低频慢变信号,洞体应变、水管倾斜仪的响应存在较大差异,这种差异可能导致记录数据中出现孤立或零星的异常变化,且在同点其他数据中找不到踪迹。本文结论在云龙台、永胜台多种同点仪器的观测数据中得到证实。  相似文献   

10.
在室内水池内以五层笼摞叠养殖方式,试验了入笼时平均壳长21.2 mm(平均体重1.1 7 g)、37.0 mm(平均体重5.43 g)、51.8 mm(平均体重16.08 g)小、中、大3种规格的九孔鲍的不同放养密度对其生长的影响.笼子大小为40 cm×30 cm×12 cm.小规格设每笼放养量为25、30、35、40、45与50只6种密度;中为25、30、35、40、与45只5种密度;大为20、25、30与40只4种密度.经60 d试验,结果表明(1)小个体组以30只/笼生长最快,平均160μm/d,33 mg/d;(2)中个体组以25只/笼生长最快,平均123um/d,62 mg/d;(3)大个体组以20只/笼生长最快,平均95 μm/d,116 mg/d.  相似文献   

11.
Nitrogen balance method and nitrogen-free diet were used in this study to determine nitrogen maintenance requirement (NM) and nitrogen maintenance requirement per unit metabolism body weight (NM’) of black porgy Acanthopagrus schlegeli. Fish with body weight (BW) of 50, 80, 120, 160 and 200 g were fed by the diets containing three graded levels of crude protein (380, 420 and 460 g/kg). The results from nitrogen balance experiment showed that the amount of nitrogen deposition varied from 0.15 to 0.31 mg/g BW...  相似文献   

12.
Nitrogen balance method and nitrogen-free diet were used in this study to determine nitrogen maintenance requirement (NM) and nitrogen maintenance requirement per unit metabolism body weight (NM′) of black porgy Acanthopagrus schlegeli. Fish with body weight (BW) of 50, 80, 120, 160 and 200 g were fed by the diets containing three graded levels of crude protein (380, 420 and 460 g/kg). The results from nitrogen balance experiment showed that the amount of nitrogen deposition varied from 0.15 to 0.31 mg/g BW per day, accounting for 12.2% to 21.1% of nitrogen intake. The amount of fecal nitrogen excretion varied from 0.21 to 0.32 mg/g BW per day, accounting for 16.3% to 21.6% of nitrogen intake. The endogenous nitrogen excretion, a main part of nitrogen consumption varied from 0.79 to 0.97 mg/g BW per day, accounting for 63.3 % to 68.0% of nitrogen intake. Positive correlation was found between NM and body weight, while a negative correlation was found between NM of unit body weight and the growth duration. No significant differences (p>0.05) were found in NM′ among different growth stages. The average of NM′ was 0.485 7mg/g per day. The results from nitrogen-free diet experiment showed that a negative correlation between NM and feed intake of nitrogen-free diet. NM increased with the decrease of feed intake of fish. The average of NM was 0.482 9 mg/g BW per day that was close to 0.483 8 mg/g BW obtained from fish with 120 g BW in nitrogen balance experiment. The nitrogen balance method is recommended to be a better method for determining NM in consideration of fish stress and result stability. This study also provides a calculated result of the protein content in diets, which is necessary for maintaining fish body protein at different growth stages. The calculation was based on the amount of nitrogen required for maintaining body protein per kg BW. Supported by Scientific Research Project Grant (No.2004C100059) from the city government of Ningbo, China.  相似文献   

13.
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   

14.
A 21-d laboratory experiment was conducted to study,the phosphorus (P) utilization of two different diets by redlip mullet Liza haematocheila T.& S.Sand-filtered water in salinity 30 and temperature 25℃ was used.Twenty-nine fish individuals were divided into three groups:11 to group 1 (G1) fed on diet l,11 to group 2 (G2) fed on diet 2,and 7 to contrast group.Diet 1 was a commercial feed,more valuable in nutrition than diet 2 that similar to natural detritus.The results show the intake phosphorus (IP) of G1 was significantly higher than that of G2,and both increased linearly with body size at a certain amount of diet.The retention phosphorus (RP) in fish of G1 was lower than G2.The relationship between retention phosphorus and body size was positive and stronger in G2.Significant difference in faecal phosphorus (FP) was found between G1 and G2.Body size significantly impacted the excretion phosphorus (EP) in G1 but G2.The loss of intake phosphorus in G1 was 10.83-20.27mg per g fish weight gain,higher than that in G2 for 6.63-9.56.Of the phosphorus,about 10% was allocated into growth,50% in faeces,and the rest lost in excretion.The main part of phosphorus was lost in faeces but excretion.The phosphorus budget of the fish could be described as 100IP=7.40RP+47.39FP+36.63EP (Diet 1) or 100IP=11.93RP+56.64FP+21.76EP (Diet 2).  相似文献   

15.
We evaluated the dietary protein requirements of juvenile turbot (Scophthalmus maximus L.) and their effects on aquatic quality. Five experimental diets were formulated containing 450, 480, 500, 520, and 540 g/kg. Each diet was randomly assigned to triplicate groups of juvenile turbot (mean initial body weight 34.5 ± 5.5 g) for 88 d. Both the weight gain ratio and feed efficiency increased with increasing dietary protein up to 500 g/kg, but no further improvement was detected when dietary protein levels were >500 g/kg. Protein intake and digestion increased with protein levels, while fecal nitrogen and nitrogen content in seawater increased only when dietary protein exceeded 500 g/kg. Protein digestibility was highest at intermediate dietary protein levels. Chemical oxygen demand, nitrite-nitrogen (NO2--N) and phosphatic-phosphor (PO43--P) levels increased in the rearing water as dietary protein levels increased. The optimum eco-nutrition level of dietary protein for juvenile turbot was 500 g/kg under the current experimental conditions. The diets containing 540 and 500 g/kg protein had similar growth rates and feed conversion ratios, but levels of ammonia (NH4+) and nitrogen were considerably higher in the water and feces, respectively, at the higher level of dietary protein. The difference in the pattern of change between body weight gain and ammonia concentration in water with increasing dietary protein is described by rhomb characteristics.  相似文献   

16.
Harmful algal blooms (HABs) have led to extensive ecological and environmental issues and huge economic losses. Various HAB control techniques have been developed, and biological methods have been paid more attention. Algicidal bacteria is a general designation for bacteria which inhibit algal growth in a direct or indirect manner, and kill or damage the algal cells. A metabolite which is strongly toxic to the dinoflagellate Alexandrium tamarense was produced by strain DH46 of the alga-lysing bacterium Alteromonas sp. The culture conditions were optimized using a single-factor test method. Factors including carbon source, nitrogen source, temperature, initial pH value, rotational speed and salinity were studied. The results showed that the cultivation of the bacteria at 28°C and 180 r min?1 with initial pH 7 and 30 salt contcentration favored both the cell growth and the lysing effect of strain DH46. The optimal medium composition for strain DH46 was determined by means of uniform design experimentation, and the most important components influencing the cell density were tryptone, yeast extract, soluble starch, NaNO3 and MgSO4. When the following culture medium was used (tryptone 14.0g, yeast extract 1.63g, soluble starch 5.0 g, NaNO3 1.6 g, MgSO4 2.3 g in 1L), the largest bacterial dry weight (7.36 g L?1) was obtained, which was an enhancement of 107% compared to the initial medium; and the algal lysis rate was as high as 98.4% which increased nearly 10% after optimization.  相似文献   

17.
乌苏里江唇耗氧率和窒息点的初步研究   总被引：2，自引：0，他引：2  
进行不同温度和不同规格人工养殖的乌苏里江唇(Hemibarbus labeo)耗氧量(MO2)、耗氧率(WO2)和窒息点(SO2)的初步测定。结果表明:水温16~28℃范围内,随着水温的升高,耗氧率、耗氧量和窒息点都表现出增大的变化趋势。温度和耗氧率的回归方程:1龄鱼体重11 g的为WO2=0.0142T-0.0863(R2=0.9617),2龄鱼体重60 g的为WO2=0.0138T-0.1121(R2=0.97);温度和窒息点的回归方程:1龄鱼体重8 g的为SO2=0.0298T-0.1891(R2=0.977 8),2龄鱼体重40 g的为SO2=0.048 8T-0.402 5(R2=0.999 7)。体重20~100 g范围内,水温25℃时,随着体重规格的增大,耗氧量逐渐升高,耗氧率逐渐减小。体重和耗氧率的回归方程为WO2=0.7825W-0.2898(R2=0.947 4),体重和耗氧量的回归方程为MO2=0.7837W0.7097(R2=0.991 6)。唇鱼的昼夜耗氧率(水温25℃,体重72 g)有一定的变化趋势,早间4~10时耗氧率较高,平均在0.332±0.046 mg/(g.h),午间11~19时中等,在0.287±0.030 mg/(g.h),晚间20~3时较低,在0.251±0.029 mg/(g.h)。  相似文献   

18.
采集采自山东某养殖场的栉孔扇贝(Chlamys farreri)健康贝和病贝的血淋巴,测定其血浆蛋白浓度、血浆蛋白图谱和相对分子质量,以及血浆抗菌活性、凝集素活性等几种重要的体液免疫因素,研究环境胁迫对血浆蛋白及其抗菌活性的影响。结果表明:栉孔扇贝(C.farreri)血浆蛋白质量浓度约1 260~1 650μg/mL;血浆蛋白SDS-PAGE图谱显示3条蛋白带,相对分子质量分别为34 000、25 000和14 000;健康贝血浆抗菌活性指数BI为0.34,病贝BI为0.21;凝集素活力水平为1.602~2.204。氨氮胁迫下血浆蛋白浓度下降约780μg/mL,凝集素活力下降为1.301;高温胁迫下血浆蛋白质量浓度下降约为900μg/mL,凝集素活力为1.903;高盐胁迫下血浆蛋白浓度下降约为990μg/mL,凝集素活力为2.204。  相似文献   

19.
A 21-d laboratory experiment was conducted to study, the phosphorus （P） utilization of two different diets by redlip mullet Liza haematocheila T. ＆ S. Sand-filtered water in salinity 30 and temperatare 25℃ was used. Twenty-nine fish individuals were divided into three groups： 11 to group 1 （G1） fed on diet 1, 11 to group 2 （G2） fed on diet 2, and 7 to contrast group. Diet 1 was a commercial feed, more valuable in nutrition than diet 2 that similar to natural detritus. The results show the intake phosphorus （IP） of G1 was significantly higher than that of G2, and both increased linearly with body size at a certain amount of diet. The retention phosphorus （RP） in fish of G1 was lower than G2. The relationship between retention phosphorus and body size was positive and stronger in G2. Significant difference in faecal phosphorus （FP） was found between G1 and G2. Body size significantly impacted the excretion phosphorus （EP） in G1 but G2. The loss of intake phosphorus in G1 was 10.83-20.27 mg per g fish weight gain, higher than that in G2 for 6.63-9.56. Of the phosphorus, about 10% was allocated into growth, 50% in faeces, and the rest lost in excretion. The main part of phosphorus was lost in faeces but excretion. The phosphorus budget of the fish could be described as 100IP = 7.40RP ＋ 47.39FP ＋ 36.63EP （Diet 1） or 100IP = 11.93RP ＋ 56.64FP ＋ 21.76EP （Diet 2）.  相似文献   

20.
Polychaete Neanthes japonica is a species geographically specific in China and Japan with important scientific implication and commercial value. In this study, the relations of body weight, salinity and temperature to oxygen consumption and ammonia excretion of N. japonica were determined. Three different groups in body weight (large: 2.34±0.36 g, middle: 1.50±0.21 g and small: 0.62±0.12 g) were set for all experiments. Results show that the body weight is negatively related to the rates of oxygen consumption and ammonia excretion; and the relationship is significant. The oxygen consumption and ammonia excretion at 24°C decreased at salinity from 5 to 30 and increased above 30, indicating that both lower and higher salinity are adverse and certain degree of salinity stress is necessary for enhancing the energy demand. At salinity 30, rising temperature from 18°C to 30°C, the oxygen consumption increased before 27°C and then decreased. However, the relation of ammonia excretion and temperature seems more complex. Two-way ANOVA shows that salinity, temperature and body weight all have a significant effect on the oxygen consumption and ammonia excretion of the worm. Moreover, interaction between salinity/temperature and body weight is also significant. O:N (oxygen/nitrogen) ratio varies greatly in this case from 5.97 to 463.22, indicating that N. japonica can regulate the type of metabolic substrate against environment changes. Supported by the National Natural Science Foundation of China (No. 30490233) and the Three-Gorge Project and the Estuarine Environment (No. SX2004-018) from the Three Gorges Project Construction Committee  相似文献   

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