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71.
砷、铜、苯酚对鲤鱼(Cyprinus carpio Linn.)的联合毒性研究   总被引:3,自引:0,他引:3  
应用微核试验、聚丙烯酰胺凝胶电泳和酯酶活性测定技术,比较和分析了42d内饲养于ρ(Cu^2 )0.01mg/L、ρ(As^3 )0.1mg/L、ρ(Phe)0.005mg/L及其二二 且合物和三组合物溶液中鲤鱼嗜多染红细胞微核率,肝、肾脏酯酶活性和同工酶谱,结果显示,ρ(Cu^2 )0.01mg/L对鲤鱼嗜多染红细胞微核无诱发作用,肝、肾脏酯酶活性无抑制作用;ρ(Phe)0.005mg/L和ρ(As^3 )0.1mg/L溶液中鲤鱼随时间 延长其微核率相应升高,其肝、肾脏酯酶活性减弱 ,同工酶带减少,砷、铜、苯酚间协同作用增大鲤鱼微核诱发效应,肝、肾脏酯酶活性减弱,同工酶带减少,因此,建议对现行渔业水质标准应作进一步验证实验,要充分考虑污染物间协同效应,以便使渔业水质标准更符合实际。  相似文献   
72.
通过对胡萝卜鲢鱼丸子的配方和制作工艺试验,得出了鱼肉、肥膘、淀粉、盐分及胡萝卜颗粒的最佳配比,使产品达到营养化、功能化、方便化的目的。  相似文献   
73.
五种多环芳烃化合物对鲤鱼肝微粒体芳烃羟化酶的诱导   总被引:3,自引:0,他引:3  
以鲤鱼肝微粒体为实验体系,研究了被五种多环芳烃(PAH)化合物菲、9,10-菲醌、芘、1-羟基芘、苯并芘污染后,其芳烃羟化酶(AHH)的活性变化,发现多环芳烃对AHH的诱导具有良好的剂量效应关系.AHH活性升高的大小可以作为监测多环芳烃对水体污染程度的一种生物指标.五种多环芳烃对AHH诱导能力的大小为1-羟基芘>苯并芘;9,10-菲醌>芘>菲,与其毒性大小相关.  相似文献   
74.
氟对鲤鱼脑抗氧化系统及细胞凋亡的影响   总被引:1,自引:1,他引:0  
以鲤鱼为受试材料,研究了氟化钠对其脑组织的抗氧化系统、组织结构和细胞凋亡的影响.结果发现,染毒30 d时,随氟化钠浓度的升高,SOD、GSH活性表现为先诱导后抑制的趋势;暴露60 d与90 d后,SOD、GSH活性主要表现为抑制.而MDA水平在整个暴露实验期间均呈增高趋势.暴露90 d后,脑组织切片的显微观察结果显示,氟化钠能导致鲤鱼脑组织血栓形成及各细胞层结构发生病理学改变,并具有剂效相关性.生物检测结果显示,随着氟化钠暴露剂量增大,鱼脑细胞凋亡率的增加与MDA水平的升高呈正相关关系(r=0.9968),而Bcl-2的表达减弱与SOD、GSH活性呈正相关关系(r=0.9198,0.9889).  相似文献   
75.
以静水法生物测试研究了对二氯苯和镉对草鱼(Ctenopharyngodon idellus)的联合毒性效应,并采用Marking水生毒理联合毒性相加指数法对联合毒性效应进行了评价.结果表明, 对二氯苯和镉对草鱼的单一毒性作用时,24、48、72和96 h对二氯苯对草鱼的LC50分别是10.11、9.04、8.52和7.83 mg/L; 24、48、72和96 h镉对草鱼的LC50分别是40.02、35.05、28.99和24.41 mg/L,因此对二氯苯的毒性大于镉的毒性. 对二氯苯和镉对草鱼种的联合毒性作用,当采用毒性1∶1进行试验时,暴露时间分别为24、48、72、96 h时AI>0,联合作用结果为协同作用,而当采用浓度1∶1进行试验时,表现出暴露时间为24、48、72 h的AI<0,联合作用结果表现为拮抗作用,而暴露时间为96 h时AI>0,联合作用结果则为协同作用,即随着暴露时间的增加,对二氯苯和镉的联合毒性作用从拮抗作用转变为毒性剧增的协同作用.  相似文献   
76.
Abstract

Acute and subacute 2,4‐D toxicity to carp (Cyprinus carpio L.) were investigated. Acute toxicity (LC‐ 50) was investigated in semi‐static test during a 24, 48, and 96‐ hours exposition. Subacute toxicity was investigated by exposing fish to different 2,4,‐D concentrations (150, 200, and 250 mg/L) for 14 days. Biochemical and morphological changes in certain organs and tissues were investigated.

LC‐ 50 values at 24 hours exposure was 310.0 mg/L, 295.0 mg/L for 48 hours, and 270.0 mg/L for 96 hours exposure.

Subacute toxicity tests show that 2,4‐D induce changes in the enzyme activities (AP, GOT, GPT) and morphological changes in the gills, liver and kidneys, but changes are of limited biological importance.  相似文献   
77.
78.
Lowland rice fields constitute a semi aquatic environment, which is potentially suitable for fish production. Little is known about the effect of fish on greenhouse gas emissions from integrated rice–fish systems. An experiment was carried out at the Bangladesh Agricultural University to assess the effect of the stocking of fish on methane emissions from rice fields. Common carp, Cyprinus carpio L., and Nile Tilapia, Oreochromis niloticus (L.) were stocked in a mixed culture and subjected to three different input regimes: (1) urea fertilization according to the recommendation of the Bangladesh Rice Research Institute (BRRI), (2) supplementary feeding at 2 × maintenance level and (3) an elevated feeding schedule where 4 × maintenance level was fed initially and 2 × maintenance level towards the end of the growth period. Rice only with urea fertilization according to BRRI-recommendation was included as the control. The presence of fish increased methane emissions in all three rice–fish treatments. Average emission over the cropping season was 34, 37, and 32 mg m−2 h−1 in the rice–fish treatments, respectively, and 20 mg m−2 h−1 in rice only. Apart from an increase in methane emission, a significant drop (p < 0.05) in floodwater pH and dissolved oxygen concentration was observed in the rice–fish plots. Both parameters were the lowest in the treatment where a higher feeding rate was provided. Due to the fish activity, floodwater in the rice–fish treatments was more turbid, as reflected in higher particulate inorganic matter (PIOM). An elevated level of dissolved methane was observed in the floodwater of the feed supplemented rice–fish plots. Methane emissions showed negative correlation with morning and afternoon pH of the floodwater (r = −0.46; r = −0.56, p < 0.001) and morning and afternoon dissolved oxygen level (r = −0.53; r = −0.46, p < 0.001). Positive correlations were recorded between morning and afternoon floodwater temperature (r = 0.49; r = 0.44, p < 0.001) and with air temperature (r = 0.54, p < 0.001). The results suggest that the stocking of fish has an increasing effect on methane emissions from rice fields.  相似文献   
79.
ABSTRACT Changes in water chemistry, water clarity, and planktonic chlorophyll a were measured as hydrilla (Hydrilla verticillata) abundance increased and then decreased in Lake Baldwin, Florida. Grass carp (Ctenopharyngodon idella) were used to eliminate submersed macrophytes. No major trends in lake pH, conductivity, or total nitrogen concentrations occurred in association with changes in hydrilla levels. Increased Secchi disc transparency and reductions in total alkalinity, calcium, magnesium, potassium, total phosphorus, and chlorophyll a concentrations occurred as hydrilla abundance increased. Large increases in the chemical parameters and a reduction in Secchi disc transparency occurred as hydrilla decreased and was eliminated from the lake by grass carp. The effects of hydrilla on lake water chemistry are related to the percentage of the lake's volume infested with hydrilla and macrophyte standing crop.  相似文献   
80.
ABSTRACT: Fishing is a popular form of recreation in the state of Illinois. Despite seemingly endless varieties of fishing opportunities, limited public access, distant location of lakes with respect to population centers, chemical contaminants in some waters, and the desire for species not naturally found in Illinois have engendered an alternate form of recreational land use, the daily fee fishing area. A fee area is any privately controlled body of water or waters where a fee is charged for fishing. Such operations must Low licensed by the state of Illinois. Fee areas are almost entirely comprised of existing man-made impoundments, particularly farm ponds. They are usually stocked on a put and take basis. The most common species utilized in Illinois are carp and channel catfish. Fee areas are concentrated in the southwestern part of the state and near major metropolitan centers. Even though the number of fee areas has declined during the past decade, the role of such operations remains important to the overall picture of fishing in Illinois.  相似文献   
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