水質(zhì)監(jiān)控技術(shù)-Water quality monitori

水質(zhì)監(jiān)控技術(shù)Waterqualitymonitoringtechnology--水質(zhì)監(jiān)控技術(shù)課程組WaterqualitymonitoringTechnologyCoursegroup養(yǎng)殖水質(zhì)亞硝酸鹽氮的檢測(cè)與調(diào)控Detectionandregulationofnitritenitrogeninaquaculturewater《水質(zhì)監(jiān)控技術(shù)》課程WaterQualityMonitoringTechnology水體中亞硝酸鹽氮對(duì)養(yǎng)殖生物的毒性及影響因素

Toxicityandinfluencingfactorsofnitritenitrogeninwatertoaquacultureorganisms

學(xué)習(xí)目標(biāo)Learningobjective掌握水體亞硝酸鹽氮的毒性機(jī)理和養(yǎng)殖生物的中毒表現(xiàn)；Tounderstandthetoxicmechanismofnitritenitrogeninwaterandthetoxicmanifestationsofaquacultureorganisms;掌握水體亞硝酸鹽氮毒性的影響因素。Tounderstandtheinfluencingfactorsofnitritenitrogentoxicityinwater.學(xué)習(xí)目標(biāo)1.Learningobjective1學(xué)習(xí)目標(biāo)2.Learningobjective2水體亞硝酸鹽氮的毒性機(jī)理Toxicitymechanismofnitritenitrogeninwater.亞硝酸鹽會(huì)影響魚(yú)蝦蛙等動(dòng)物體內(nèi)抗氧化酶的活性，同時(shí)也影響溶菌酶的活力，從而降低動(dòng)物的免疫能力；Nitritecanaffecttheactivityofantioxidantenzymesandlysozymeinfish,shrimp,frogandotheranimals,thusreducingtheimmunityofanimals.養(yǎng)殖水體亞硝酸鹽濃度過(guò)高時(shí)，可通過(guò)魚(yú)蝦類體表的滲透與吸收作用進(jìn)入血液，使血液中的亞鐵血紅蛋白被氧化成高鐵血紅蛋白，由于高鐵血紅蛋白不能與氧氣結(jié)合，從而導(dǎo)致血液載氧能力下降甚至喪失。Whentheconcentrationofnitriteinaquaculturewateristoohigh,itcanenterthebloodthroughtheinfiltrationandabsorptionofthebodysurfaceoffishandshrimp,sothattheferrohemoglobininthebloodisoxidizedtomethemoglobin.Becausemethemoglobincannotcombinewithoxygen,theoxygencarryingcapacityofthebloodisreducedorevenlost.不同濃度的亞硝酸鹽對(duì)魚(yú)蝦的影響Effectsofdifferentconcentrationsofnitriteonfishandshrimp.0~0.1㎎/L(以氮計(jì))(innitrogen)正常養(yǎng)殖水體的亞硝酸鹽濃度低于0.1㎎/L，魚(yú)蝦水生動(dòng)物在此條件下，能夠正常自由地生活，不會(huì)造成任何健康損害。Theconcentrationofnitriteinnormalaquaculturewaterislowerthan0.1㎎/L,andaquaticanimalsoffishandshrimpcanlivenormallyandfreelyundersuchconditionswithoutcausinganyhealthdamage.不同濃度的亞硝酸鹽對(duì)魚(yú)蝦的影響Effectsofdifferentconcentrationsofnitriteonfishandshrimp.0.1~0.5㎎/L(以氮計(jì))(innitrogen)

養(yǎng)殖對(duì)象的生理功能紊亂，影響其生長(zhǎng)或引起其他疾病的發(fā)生，造成魚(yú)、蝦慢性亞硝酸鹽中毒，表現(xiàn)為攝食量下降，生長(zhǎng)不明顯，活動(dòng)力減弱，鰓及鰓蓋內(nèi)表面血管呈暗紫紅色，呼吸困難，游動(dòng)緩慢，騷動(dòng)不安或反應(yīng)遲鈍，同時(shí)體表呈現(xiàn)不正常的色澤。Thephysiologicaldisordersoftheculturedobjectsaffecttheirgrowthorcausetheoccurrenceofotherdiseases,resultinginchronicnitritepoisoningoffishandshrimp,whichismanifestedasdecreasedfoodintake,insignificantgrowth,weakenedactivity,darkpurpleredbloodvesselsontheinnersurfaceofthegillsandgillcovers,dyspnea,slowswimming,agitationorslowresponse,andabnormalcoloronthebodysurface.

亞硝酸鹽中毒的對(duì)蝦外表癥狀有黑鰓、黃鰓、肝胰臟模糊不清晰，解剖后顯微鏡觀察，鰓絲腫脹充水，甚至糜爛粘有污物，腸道充血發(fā)炎，肝胰臟空泡甚至糜爛。Theoutwardsymptomsofnitritepoisoningofshrimpincludeblackgills,yellowgillsandvaguehepatopancreas.Microscopicobservationafterdissectionshowsthatthegillfilamentsareswollenandfilledwithwater,andthereareevenfilamentsstickytoerosion,intestinalcongestionandinflammation,hepatopancreasvacuoleandevenerosion.黑鰓病不同濃度的亞硝酸鹽對(duì)魚(yú)蝦的影響Effectsofdifferentconcentrationsofnitriteonfishandshrimp.>0.5㎎/L(以氮計(jì))(innitrogen)魚(yú)中毒癥狀繼續(xù)加劇，體力衰退，游泳無(wú)力，某些代謝器官功能衰竭，并大量死亡。Thesymptomsoffishpoisoningcontinuetoworsen,withphysicaldecline,inabilitytoswim,failureofcertainmetabolicorgans,andalargenumberofdeaths.亞硝酸鹽偏高的危害更主要是表現(xiàn)在對(duì)蝦蛻殼期。會(huì)引起蛻殼期的對(duì)蝦因?yàn)槿毖?、中毒而蛻殼不遂，出現(xiàn)大量軟殼蝦，常常引起蛻殼期大量“偷死”。Theharmofhighnitriteismainlymanifestedinthemoultingperiodofprawn.Itwillcausetheshrimpsinthemoultingperiodtomoultbecauseofhypoxiaandpoisoning,andtherearealargenumberofsoft-shellshrimps,whichoftencausealargenumberof"stealingdeath"inthemoultingperiod.急性中毒和浮頭很相似，都呈現(xiàn)缺氧癥狀，但是兩者最大的區(qū)別是亞硝酸鹽中毒在太陽(yáng)出來(lái)后魚(yú)還不下水，有時(shí)甚至整天都在水面活動(dòng)，晴天也不例外。Acutepoisoningandfloatingheadareverysimilar,bothpresenthypoxiasymptoms,butthebiggestdifferencebetweenthetwoisthatnitritepoisoningfishdonotgointothewaterafterthesuncomesout,sometimesevenalldaylongonthesurfaceofthewater,evenonsunnydays.不同濃度的亞硝酸鹽對(duì)魚(yú)蝦的影響Effectsofdifferentconcentrationsofnitriteonfishandshrimp.亞硝酸鹽的安全濃度和致死濃度Safeandlethalconcentrationsofnitrite.品種variety安全濃度(mg/L)Safeconcentration品種variety致死濃度(mg/L)Lethalconcentration一般淡水魚(yú)Generalfreshwaterfish<1虹鱒Rainbowtrout0.24一般海水魚(yú)CommonMarinefish<1鯉魚(yú)carp2.6一般海水蝦Commonseashrimp0.25草魚(yú)Grasscarp4.6羅氏沼蝦Macrobrachium

rosenbergii0.1羅非魚(yú)tilapia16水生動(dòng)物不同種類、品種及個(gè)體對(duì)亞硝酸鹽的耐受性不同，因而，對(duì)不同種類魚(yú)蝦蟹的安全密度差異很大。為確保魚(yú)蝦蟹的安全（尤其在育苗期），亞硝酸鹽含量應(yīng)控制在0.1㎎/L以下。Differentkinds,varietiesandindividualsofaquaticanimalsTolerancetonitriteisdifferent,so,Thesafetydensityofdifferentkindsoffish,shrimpandcrabsispoorIt'sabigdifference.Toensurethesafetyoffish,shrimpandcrabs(especiallyIntheseedlingstage),nitritecontentshouldbecontrolledBelow0.1㎎/L.影響亞硝酸鹽毒性的因素Factorsinfluencingnitritetoxicity溶氧：

低氧會(huì)使動(dòng)物受到高濃度亞硝酸鹽影響的風(fēng)險(xiǎn)增加Dissolvedoxygen:Lowoxygenputsanimalsatincreasedriskofhighconcentrationsofnitrite氨氮：氨氮濃度高會(huì)增加亞硝酸鹽的毒性Ammonianitrogen:Highconcentrationsofammonianitrogenincreasethetoxicityofnitrites氯化物：水中氯化物濃度高可阻止動(dòng)物對(duì)亞硝酸鹽的吸收，降低毒性氯化物與亞硝酸鹽之比為10:1時(shí)可消除亞硝酸鹽對(duì)溝鯰的毒性Chloride:Highchlorideconcentrationinwatercanpreventtheabsorptionofnitritebyanimals,andreducethetoxicityofnitritetocatfishwhentheratio