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131.
通过试验生态学方法,采用静水系统,对我国北方常见的污损生物匍茎草苔虫(Bugula stolonifera Ryland,1960)排氨率进行了初研究,主要包括匍茎草苔虫在饥饿状态下,温度对其排氨率的影响;温度和盐度交互作用对其排氨率的影响;温度和pH交互作用对其排氨率的影响。为预防控制海洋污损生物对养殖生物正常生长存活有着非常重要的意义,也为更深一步规划出有效的防治方法提供一定的基础科学依据。具体试验结果为:1.温度对匍茎草苔虫的排氨率具有极其显著的影响,在12~27℃范围内,呈1个峰值变化,在24℃时其排氨率达到最高值;2.温度与盐度的交互作用对其排氨率有显著的影响,在12~27℃条件下,盐度在16‰~40‰范围内,呈1个峰值变化,在盐度32‰时其排氨率达到最高值;3.温度与pH的交互作用对其排氨率有极其显著的影响,在12~27℃条件下,pH在5~10范围内,呈1个峰值变化,在pH为8时其排氨率达到最高值。 相似文献
132.
Douglas R. Tocher John D. Castell James R. Dick John R. Sargent 《Fish physiology and biochemistry》1994,13(6):451-461
The direct effects of osmotic pressure (salinity) on growth performance and lipid composition were investigated in fish cells
in culture. Cell lines from a relatively stenohaline marine species, turbot (Scophthalmus maximus) (TF) and an anadromous species, Atlantic salmon (AS) were cultured in media supplemented with NaCl to produce osmotic pressures
varying from 300 to 500 mOsm kg−1. The growth rates of the two cell lines were affected in a similar manner by the salinity of the media with the rank order
for both peak cell numbers and growth rates up to the day of peak cell number being 300 > 350 > 400 > 450 > 500 mOsm kg−1. Cell death occurred in both cell lines in older cultures at all salinities with the greatest loss of viable cells in media
of 300 and 350 kg−1. However, there were quantitative and qualitative differences between the cell lines in their lipid metabolism in response
to the salinity of the media. The lipid content expressed per cell showed a positive correlation between lipid per cell and
salinity in TF cells, but this was less apparent in AS cells. The percentage of total polar lipid classes increased with increasing
salinity in TF cells due mainly to graded increases in the percentages of choline phospholipids. In contrast, there were no
significant differences in the proportions of polar and neutral lipid classes with salinity in AS cells. The only significant
effect of salinity in AS cells was a decreased proportion of dimethylacetals in total lipid at the highest salinity. The same
significant effect of salinity on dimethylacetal content of total lipid was observed in TF cells. However, in addition there
was a graded decrease in the percentage of 18:2n-9 in TF cell total lipid with increasing salinity. This was accompanied by
increased percentages of total n-3 and n-6 PUFA with higher proportions of both groups of PUFA at 450 and 500 compared with
300 mOsm kg−1. The results show that environmental salinity, in the absence of hormonal or other physiological stimuli, has direct effects
on the growth and lipid metabolism of fish cells and that these effects differ in cells from different fish species. 相似文献
133.
Sujata Mohapatra Rajesh Kumar Srianga Tilak Patnaik Choudhury Suryakant Mishra Lakshman Sahoo Jitendra Kumar Sundaray 《Aquaculture Research》2020,51(8):3230-3236
Monocrotophos (MCP) is one of the organophosphate pesticides extensively used in agriculture and animal husbandry. The present study reports the effects of sub‐lethal concentrations of MCP on gonadosomatic index (GSI), gonadal histology and breeding fitness of the fish Anabas testudineus. The fish were exposed to three sub‐lethal concentrations of monocrotophos (T1: 3.5 mg/L, T2: 5.3 mg/L and T3: 10.6 mg/L) for 45 days with 12 fish (males and females in equal numbers) in each tank, and one group was kept as control (C) without any treatment. GSI decreased in all treatment groups in comparison with control. Significant decrease in fertilization and hatching rate was observed at all concentrations in comparison with control on 15, 30 and 45 days of monocrotophos exposure. The decreased vitellogenesis, disruption of follicular wall and oocyte atresia were observed in all the treated females at 30 and 45 days of exposure. Rupture of seminiferous tubules was noticed in all the treated males irrespective of exposure periods. The results thus indicated that monocrotophos could deleteriously impact the gonadal structure and function in A. testudineus, which could seriously impact the reproductive success of the animal. 相似文献
134.
为了建立观赏海藻大规模微繁技术,研究了温度和盐度对台湾锯齿藻(Prionitis formosana)和海木耳藻(Sarcodia montagneana)生长及叶绿素含量的影响。结果表明,在实验范围内,台湾锯齿藻在35℃的条件下死亡,5~15℃藻体负生长,适宜生长温度为20~25℃;盐度为22条件下生长正常,其余盐度下均生长不良;叶绿素含量在25℃和盐度22时达到最高。海木耳藻在5℃与35℃时出现死亡,5~15℃时负生长,适宜生长温度为25~30℃;最适生长盐度为10,其余盐度下均有不同程度的生长,并且随着温度的增加生长率下降;叶绿素含量在30℃和盐度10时达到最高。 相似文献
135.
温度和盐度对鞍带石斑鱼受精卵发育及仔鱼成活率的影响 总被引:4,自引:0,他引:4
研究了在8个盐度梯度(18.3‰、19.7‰、21.2‰、23.5‰、25.6‰、27.1‰、29.5‰和31.7‰)下鞍带石斑鱼Epinephelus lanceol受精卵和仔鱼在水中的分布状态、出膜率和仔鱼存活率;在9个温度梯度(18℃、20℃、22℃、24℃、26℃、28℃、30℃、33℃和35℃)下,其受精卵孵化率、畸形率和仔鱼成活率。结果表明:(1)在水温为25~26℃,当盐度≤25.6‰时,受精卵表现为沉性;当盐度≥27.1‰时,受精卵表现为浮性。仔鱼的分布与受精卵有相似的特点,当盐度≤21.2‰时仔鱼分布在底层水体;当盐度≥27.1‰时,仔鱼集中分布在上层水体。(2)以孵化率和成活率为指标,鞍带石斑鱼孵化的适宜盐度范围为21.2‰~31.7‰,最适盐度范围为25.6‰~31.7‰。在盐度为31.7‰时仔鱼成活率最高达到75.9%。(3)鞍带石斑鱼胚胎发育的适温范围是26~30℃。28℃时受精卵孵化率、仔鱼成活率均最高,畸形率最低。 相似文献
136.
在静水系统中,骤然改变水体盐度,形成盐度脉冲;研究许氏平鲉Sebastodes fuscescens(Houttuyn)经历该脉冲后其氨氮、活性磷酸盐排泄的情况。结果表明,盐度改变后,许氏平鲉的氨氮排泄率比正常盐度(30)下呈现出不同程度的升高趋势;当盐度由30降为25和20时,随着体重增加,氨氮排泄率先增大,后又减小;当盐度由30上升为35时,氨氮排泄率随体重增加而呈下降趋势。盐度改变后,许氏平鲉的活性磷酸盐排泄率随体重增大呈先增大后减小的趋势。在同一体重下,盐度由30降至20时,活性磷酸盐的排泄率最大;盐度由30升至35时,磷的排泄率最小。方差分析表明,盐度脉冲对许氏平鲉氨氮排泄率有显著的影响(P<0.05),对活性磷酸盐排泄率的影响不显著(P>0.05)。该研究对于鱼类养殖的水质管理、养殖场的布设等有重要的指导意义。 相似文献
137.
在35d的试验周期内,研究了不同盐度(2、4、6、8)对杂交鳢(斑鳢♀×乌鳢♂)幼鱼生长及血液红细胞数量(RBC)、白细胞数量(WBC)、溶菌酶(LZM)含量、超氧化物歧化酶活性(SOD)和过氧化氢酶(CAT)活性等免疫因子的影响。结果显示,随着盐度的升高,杂交鳢增重率分别为67.81%、68.26%、71.14%、32.96%和14.26%,存活率分别为100%、100%、100%、100%和93.3%。盐度2、4组增重率和对照组差异不显著,盐度6、8组增重率和对照组差异显著(P<0.05)。随着盐度的升高,血液红细胞数量呈下降的趋势,对照组和其他组差异显著(P<0.05),而白细胞数量先急剧上升后又恢复到对照组水平,盐度6组达到最高。血液中溶菌酶浓度随着盐度变化出现波动,盐度6组达到最高,且与对照组差异显著(P<0.05),盐度8组溶菌酶浓度有所回降,但仍显著高于对照组(P<0.05)。超氧化物歧化酶活性变化趋势与溶菌酶浓度变化趋势相似,各组超氧化物歧化酶活性均高于对照组且差异显著(P<0.05)。当盐度升至6时,超氧化物歧化酶活力升至最高。过氧化氢酶活性随着盐度的增加逐步升高,盐度8组达到最高,且各组与对照组差异显著(P<0.05)。 相似文献
138.
为探明钝缀锦蛤的摄食生理,以北海近海人工中间培育和养殖的钝缀锦蛤为试验材料,室内条件下采用试验生态法研究温度、盐度和体质量对钝缀锦蛤滤食率与同化率的影响。试验结果表明,在温度17~33℃条件下,滤食率随温度的升高,呈先升后降的趋势,滤食率(y)与水温(x)之间的回归方程为y=-4.338×10-3 x^3+0.311x2-6.915x+49(r2=0.999),同化率随着温度的升高而增大,温度对同化率的影响显著(P<0.01);在盐度18~33条件下,滤食率随盐度的升高呈先增后降的趋势,盐度27~30时保持较高的滤食率,滤食率(y)与盐度(x)之间的回归方程为y=-0.027x^2+1.638x-19.52(r^2=0.994),同化率随盐度的升高而增大,盐度为30时同化率最高,盐度对同化率的影响显著(P<0.01);滤食率随体质量增加而降低,体质量对同化率影响不显著(P>0.05)。研究表明,钝缀锦蛤属典型热带和亚热带种群品种,适宜生活在温度和盐度较稳定的潮下带区域,非广温广盐性贝类。 相似文献
139.
140.
Peng Zhang Shuanglin Dong Fang Wang Han Wang Wei Gao Yi Yan 《Aquaculture Research》2012,43(11):1611-1619
Sea cucumber, Apostichopus japonicus (Selenca), tolerates salinity fluctuations inhabiting intertide zone. This study deals with growth, food intake, food conversion and the bioenergetic responses of the red variant (wet weight of 2.60 ± 0.11g) and green variant (wet weight of 2.56 ± 0.08 g) A. japonicus to different salinities of 22, 26, 30, 34, and 38 psu at 16.5 ± 0.5°C. The results showed that salinity had a significant effect on specific growth rate (SGR) of both green and red variants A. japonicus (P < 0.05). Both colour variants of sea cucumber had highest SGR at 30 psu, and then decreased when salinity below or above this point. Maximum SGR (the green 1.07 ± 0.08% day?1, the red 1.14 ± 0.09% day?1 respectively) is related with maximum food intake (FI) and highest food conversion efficiency (FCE) (P < 0.05) occurring at 30 psu. Only under 22 psu, the green variant grew faster than the red variant (P < 0.05), and under other four salinity treatments there was no significant difference between SGR of two colour variant holothruians (P > 0.05). Values of adaptable salinity scope for green and red variants sea cucumber survival are 18.5~39 psu and 20.9~38.6 psu respectively. The average energy budget formula of sea cucumber at 30 psu was: 100C = 6G +42F +3U+49R (C, energy ingested; G, energy for growth; F, energy loss as faeces; U, energy used for ammonia excretion; R, energy loss for respiration). The sea cucumber had maximum energy ingested (C) and highest proportion of energy for growth (G) at 30 psu, and then decreased when salinity is above or below this salinity. Both red and green variants of A. japonicus deposited for growth were very low, and the energy loss in faeces and energy for respiration accounted for the majority of assimilation energy. The result clearly showed that the optimum condition for farming green and red variants A. japonicus, both with respect growth and energy allocation, is the salinity scope of 26 ~ 30 psu. 相似文献