Name: laboratory estimation of net trophic transfer efficiencies of pcb congeners to lake trout (salvelinus namaycush) from its prey
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Description: Watch this Scientific Journal Video about Laboratory Estimation of Net Trophic Transfer Efficiencies of PCB Congeners to Lake Trout Salvelinus namaycush from Its Prey at JoVE.com

This work was funded, in part, by the Great Lakes Fishery Commission and the Annis Water Resources Institute. Use of trade, product, or firm names does not imply endorsement by the U. S. Government. This article is Contribution 1867 of the U. S. Geological Survey Great Lakes Science Center.

1. مختبر التجربة <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> الحصول على الأسماك فريسة لتغذية الأسماك المفترسة أثناء التجربة. ويفضل أن يتم القبض على هذه الأسماك فريسة في الميدان، والمجمدة، وتخزينها في حوالي -30 ° C. النظر في عمليات الصيد التجارية كمصدر محتمل للأسم...

<ol>
	<li>Madenjian, C. P., Carpenter, S. R., Rand, P. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Why+are+the+PCB+concentrations+of+salmonine+individuals+from+the+same+lake+so+highly+variable?.">Why are the PCB concentrations of salmonine individuals from the same lake so highly variable?.</a> Canadian Journal of Fisheries and Aquatic Sciences. 51 (4), 800-807 (1994).</li><li>Madenjian, C. P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Net+trophic+transfer+efficiency+of+PCBs+to+Lake+Michigan+coho+salmon+from+their+prey.">Net trophic transfer efficiency of PCBs to Lake Michigan coho salmon from their prey.</a> Environmental Science and Technology. 32 (20), 3063-3067 (1998).</li><li>Thomann, R. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bioaccumulation+model+of+organic+chemical+distribution+in+aquatic+food+chains.">Bioaccumulation model of organic chemical distribution in aquatic food chains.</a> Environmental Science and Technology. 23 (6), 699-707 (1989).</li><li>Calabrese, E. J., Baldwin, L. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Performing ecological risk assessments. , (1993).</li><li>Madenjian, C. P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Variation+in+net+trophic+transfer+efficiencies+among+21+PCB+congeners.">Variation in net trophic transfer efficiencies among 21 PCB congeners.</a> Environmental Science and Technology. 33 (21), 3768-3773 (1999).</li><li>Jackson, L. J., Schindler, D. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Field+estimates+of+net+trophic+transfer+of+PCBs+from+prey+fishes+to+Lake+Michigan+salmonids.">Field estimates of net trophic transfer of PCBs from prey fishes to Lake Michigan salmonids.</a> Environmental Science and Technology. 30 (6), 1861-1865 (1996).</li><li>Gobas, F. A. P. C., Muir, D. C. G., Mackay, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dynamics+of+dietary+bioaccumulation+and+faecal+elimination+of+hydrophobic+organic+chemicals+in+fish.">Dynamics of dietary bioaccumulation and faecal elimination of hydrophobic organic chemicals in fish.</a> Chemosphere. 17 (5), 943-962 (1988).</li><li>Madenjian, C. P., O&#8217;Connor, D. V., Rediske, R. R., O&#8217;Keefe, J. P., Pothoven, S. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Net+trophic+transfer+efficiencies+of+polychlorinated+biphenyl+congeners+to+lake+whitefish+(Coregonus+clupeaformis)+from+their+food.">Net trophic transfer efficiencies of polychlorinated biphenyl congeners to lake whitefish (Coregonus clupeaformis) from their food.</a> Environmental Toxicology and Chemistry. 27 (3), 631-636 (2008).</li><li>Isosaarl, P., Kiviranta, H., Lie, &. #. 2. 1. 6. ;., Lundebye, A. K., Ritchie, G., Vartiainen, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Accumulation+and+distribution+of+polychlorinated+dibenzo-p-dioxin,+dibenzofuran,+and+polychlorinated+biphenyl+congeners+in+Atlantic+salmon+(Salmo+salar).">Accumulation and distribution of polychlorinated dibenzo-p-dioxin, dibenzofuran, and polychlorinated biphenyl congeners in Atlantic salmon (Salmo salar).</a> Environmental Toxicology and Chemistry. 23 (7), 1672-1679 (2004).</li><li>Buckman, A. H., Brown, S. B., Hoekstra, P. F., Solomon, K. R., Fisk, A. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Toxicokinetics+of+three+polychlorinated+biphenyl+technical+mixtures+in+rainbow+trout+(Oncorhynchus+mykiss).">Toxicokinetics of three polychlorinated biphenyl technical mixtures in rainbow trout (Oncorhynchus mykiss).</a> Environmental Toxicology and Chemistry. 23 (7), 1725-1736 (2004).</li><li>Burreau, S., Axelman, J., Broman, D., Jakobsson, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dietary+uptake+in+pike+(Esox+lucius)+of+some+polychlorinated+biphenyls,+polychlorinated+naphthalenes+and+polybrominated+diphenyl+ethers+administered+in+natural+diet.">Dietary uptake in pike (Esox lucius) of some polychlorinated biphenyls, polychlorinated naphthalenes and polybrominated diphenyl ethers administered in natural diet.</a> Environmental Toxicology and Chemistry. 16 (12), 2508-2513 (1997).</li><li>Madenjian, C. P., DeSorcie, T. J., Stedman, R. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ontogenic+and+spatial+patterns+in+diet+and+growth+of+lake+trout+in+Lake+Michigan.">Ontogenic and spatial patterns in diet and growth of lake trout in Lake Michigan.</a> Transactions of the American Fisheries Society. 127 (2), 236-252 (1998).</li><li>Paterson, G., Whittle, D. M., Drouillard, K. G., Haffner, G. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Declining+lake+trout+(Salvelinus+namaycush)+energy+density:+are+there+too+many+salmonid+predators+in+the+Great+Lakes?.">Declining lake trout (Salvelinus namaycush) energy density: are there too many salmonid predators in the Great Lakes?.</a> Canadian Journal of Fisheries and Aquatic Sciences. 66 (6), 919-932 (2009).</li><li>Madenjian, C. P., O&#8217;Connor, D. V., Nortrup, D. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+new+approach+toward+evaluation+of+fish+bioenergetics+models.">A new approach toward evaluation of fish bioenergetics models.</a> Canadian Journal of Fisheries and Aquatic Sciences. 57 (5), 1025-1032 (2000).</li><li>Madenjian, C. P., Pothoven, S. A., Kao, Y. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reevaluation+of+lake+trout+and+lake+whitefish+bioenergetics+models.">Reevaluation of lake trout and lake whitefish bioenergetics models.</a> Journal of Great Lakes Research. 39 (2), 358-364 (2013).</li><li>Madenjian, C. P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evaluation+of+a+lake+whitefish+bioenergetics+model.">Evaluation of a lake whitefish bioenergetics model.</a> Transactions of the American Fisheries Society. 135 (1), 61-75 (2006).</li><li>Madenjian, C. P., O&#8217;Connor, D. V., Chernyak, S. M., Rediske, R. R., O&#8217;Keefe, J. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evaluation+of+a+chinook+salmon+(Oncorhynchus+tshawytscha)+bioenergetics+model.">Evaluation of a chinook salmon (Oncorhynchus tshawytscha) bioenergetics model.</a> Canadian Journal of Fisheries and Aquatic Sciences. 61 (4), 627-635 (2004).</li><li>Madenjian, C. P., David, S. R., Rediske, R. R., O&#8217;Keefe, J. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Net+trophic+transfer+efficiencies+of+polychlorinated+biphenyl+congeners+to+lake+trout+(Salvelinus+namaycush)+from+its+prey.">Net trophic transfer efficiencies of polychlorinated biphenyl congeners to lake trout (Salvelinus namaycush) from its prey.</a> Environmental Toxicology and Chemistry. 31 (12), 2821-2827 (2012).</li><li>Madenjian, C. P., O'Connor, D. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Laboratory+evaluation+of+a+lake+trout+bioenergetics+model.">Laboratory evaluation of a lake trout bioenergetics model.</a> Transactions of the American Fisheries Society. 128 (5), 802-814 (1999).</li><li>Ballschmiter, K., Bacher, R., Mennel, A., Fischer, R., Riehle, U., Swerev, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+determination+of+chlorinated+biphenyls,+chlorinated+dibenzodioxins,+and+chlorinated+dibenzofurans+by+GC-MS.">The determination of chlorinated biphenyls, chlorinated dibenzodioxins, and chlorinated dibenzofurans by GC-MS.</a> HRC Journal of High Resolution Chromatography. 15 (4), 260-270 (1992).</li><li>Madenjian, C. P., David, S. R., Pothoven, S. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+activity+and+energy+budget+balancing+algorithm+on+laboratory+performance+of+a+fish+bioenergetics+model.">Effects of activity and energy budget balancing algorithm on laboratory performance of a fish bioenergetics model.</a> Transactions of the American Fisheries Society. 141 (5), 1328-1337 (2012).</li><li>Lieb, A. J., Bills, D. D., Sinnhuber, R. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Accumulation+of+dietary+polychlorinated+biphenyls+(Aroclor+1254)+by+rainbow+trout.">Accumulation of dietary polychlorinated biphenyls (Aroclor 1254) by rainbow trout.</a> Journal of Agricultural and Food Chemistry. 22 (4), 638-642 (1974).</li><li>Niimi, A. J., Oliver, B. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biological+half-lives+of+polychlorinated+biphenyl+(PCB)+congeners+in+whole+fish+and+muscle+of+rainbow+trout+(Salmo+gairdneri).">Biological half-lives of polychlorinated biphenyl (PCB) congeners in whole fish and muscle of rainbow trout (Salmo gairdneri).</a> Canadian Journal of Fisheries and Aquatic Sciences. 40 (9), 1388-1394 (1983).</li><li>Gobas, F. A. P. C., Wilcockson, J. B., Russell, R. W., Haffner, G. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanism+of+biomagnification+in+fish+under+laboratory+and+field+conditions.">Mechanism of biomagnification in fish under laboratory and field conditions.</a> Environmental Science and Technology. 33 (1), 133-141 (1999).</li><li>Dmitrovic, J., Chan, S. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determination+of+polychlorinated+biphenyl+congeners+in+human+milk+by+gas+chromatography+&#8211;+negative+chemical+ionization+mass+spectrometry+after+sample+clean-up+by+solid-phase+extraction.">Determination of polychlorinated biphenyl congeners in human milk by gas chromatography &#8211; negative chemical ionization mass spectrometry after sample clean-up by solid-phase extraction.</a> Journal of Chromatography B. 778 (1-2), 147-155 (2002).</li><li>Zorn, M. E., Gibbons, R. D., Sonzogni, W. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Weighted+least-squares+approach+to+calculating+limits+of+detection+and+quantification+by+modeling+variability+as+a+function+of+concentration.">Weighted least-squares approach to calculating limits of detection and quantification by modeling variability as a function of concentration.</a> Analytical Chemistry. 69 (15), 3069-3075 (1997).</li></ol>

لتقديرات أكثر دقة من γ، يجب أن يكون المجرب قادرة على تتبع بدقة كل من كمية الغذاء وضعها في كل من الدبابات وكمية من المواد الغذائية غير مأكول في كل من الدبابات أثناء التجربة. ولتحقيق ذلك، يجب أن يكون المجرب قادرة على إزالة جميع المواد الغذائية غير مأكول من الدبابات وتحد...

Of all of the factors affecting the rate at which fish accumulate contaminants, the efficiency with which fish retain contaminants from the food that they eat is one of the most important1-3. Risk assessment models have been developed to predict future risks to both people and wildlife eating contaminated fish under various scenarios of environmental contamination, and the reliability of these predictions critically depends on the accuracy of the estimates of the efficiency at which fish retain contaminants from their food4.
The efficiency with which the contaminant in the food ingested by the predator is transported through the gut wall is known as gross trophic transfer efficiency5. A portion of the quantity of the contaminant transported through the gut wall of the predator may eventually be lost through depuration and/or metabolic transformation. The efficiency with which the contaminant in the food ingested by the predator is retained by the predator, including any losses due to elimination and metabolic transformation, is known as net trophic transfer efficiency6.
Gross trophic transfer efficiency of organic contaminants to fish from their prey appears to vary with the contaminant&#8217;s chemical properties, including lipid affiliation as measured by the octanol-water partition coefficient, Kow3,7. According to an empirical relationship developed by Thomann3, gross trophic transfer efficiency is relatively high when log Kow is equal to a value between 5 and 6. Gross trophic transfer efficiency declines exponentially at a rate of 50% per unit of log Kow as log Kow increases from 6 to 10, according to the Thomann3 relationship.
Nevertheless, the gross and net trophic transfer efficiencies of polychlorinated biphenyl (PCB) congeners to fish from their prey do not appear to follow the Thomann3 relationship in most cases. Although the trophic transfer efficiencies of PCB congeners to lake whitefish (Coregonus clupeaformis) from its food followed the relationship proposed by Thomann8, trophic transfer efficiencies of PCB congeners were either just weakly related or not related at all to log Kow for Atlantic salmon (Salmo salar)9, rainbow trout (Oncorhynchus mykiss)10, coho salmon (Oncorhynchus kisutch)11, and northern pike (Esox lucius)11.
The overall goal of this study was to present a laboratory technique for estimating the net trophic transfer efficiencies of PCB congeners to a piscivorous fish from its prey. Lake trout (Salvelinus namaycush) was chosen as the piscivorous fish for our experiment because lake trout are relatively easy to maintain in laboratory tanks. Bloater (Coregonus hoyi) was selected as the prey fish to be fed to the lake trout because bloater is eaten by lake trout in its natural setting12. In addition, we determined whether the net trophic transfer efficiencies for lake trout estimated from our laboratory experiment followed the Thomann3 relationship. We also determined whether the degree of activity by the lake trout had a significant effect on net trophic transfer efficiency (&#947;) of the PCB congeners. Activity by lake trout in the Laurentian Great Lakes is believed to have recently increased because changes in the food webs have caused lake trout to allocate more energy toward searching for food13. Lake trout were forced to exercise in one set of tanks by subjecting these lake trout to relatively high flow rates, whereas the other lake trout were permitted to remain relatively inactive by subjecting them to relatively low flow rates. Finally, the specific details of our laboratory procedure that need to be carefully followed to ensure the highest degree of accuracy in the &#947; estimates and to make the laboratory results applicable to the field are discussed, as well as future directions for research building on our laboratory technique. Net trophic transfer efficiency can be estimated both in the laboratory and in the field, and advantages and disadvantages are associated with both approaches. Accuracy in the estimate of &#947; depends on the accuracy of the estimate of food consumption. The amount of food eaten by fish in the laboratory can be accurately determined when proper protocols are followed, whereas the amount of food eaten by fish in the field is typically estimated via bioenergetics modeling. Use of bioenergetics modeling to derive the amount of food eaten has the potential to introduce a substantial amount of uncertainty into the estimates of food consumption. Fish bioenergetics models have been shown to estimate food consumption with no detectable bias for the case of lake trout14,15, but considerable bias in bioenergetics model estimates of food consumption has been detected for the case of lake whitefish15,16. On the other hand, estimates of net trophic transfer efficiency estimated in the laboratory may not be applicable to the field due to a difference in feeding rates between the laboratory and the field17. Evidence from both the laboratory and the field suggest that feeding rate can influence &#947;14,17.
The methodology used in the present study for estimating &#947; in the laboratory is applicable to situations where the predator fish is fed prey fish, and the amount of prey fish eaten by the predator can be accurately tracked. To accomplish this, the experimenter must weigh all of the food before placement in the tank; and the experimenter must be able to remove all of the uneaten food from the tank, and then weigh the uneaten food. In addition, an adequate suite of mixers and blenders should be available to obtain a sufficient degree of homogenization of the samples of both predator and prey fish. Finally, the gas chromatography &#8211; mass spectrometry instrumentation used to determine the PCB congener concentrations must be capable of detecting and quantifying individual PCB congeners at relatively low concentrations.

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			<td></td>
		</tr>
		<tr height="52">
			<td height="52" style="height:52px;width:259px;">Internal standard solution&#160;</td>
			<td style="width:87px;">Cambridge Isotope Laboratories</td>
			<td style="width:119px;">EC-1410-1.2</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:259px;">PCB congener calibration standards</td>
			<td style="width:87px;">Accustandard</td>
			<td style="width:119px;">C-CSQ-SET</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:259px;">DB-XLB column (60m x 0.25mm, 0.25 micron)</td>
			<td style="width:87px;">Agilent/ J&#38;W</td>
			<td style="width:119px;">122-1262</td>
			<td></td>
		</tr>
	</tbody>
</table>

laboratory estimation of net trophic transfer efficiencies of pcb congeners to lake trout (salvelinus namaycush) from its prey

ووصف أسلوب لتقدير كفاءة المختبر من صافي الغذائية نقل (γ) من ثنائي الفينيل متعدد الكلورة (PCB) متجانسا إلى الأسماك الآكلة للأسماك من فرائسها هنا. خلال تجربة مختبرية 135 يوم، ونحن تغذية الرنجة (Coregonus hoyi) التي كانت قد اشتعلت في بحيرة ميشيغان، وتراوت البحيرة (Salvelinus namaycush) يوضع في ثماني دبابات المختبر. الرنجة هو الفريسة الطبيعية لسمك السلمون المرقط البحيرة. في أربعة خزانات، تم استخدام معدل تدفق عالية نسبيا لضمان النشاط المرتفع نسبيا من سمك السلمون المرقط البحيرة، في حين تم استخدام معدل التدفق المنخفض في خزانات الأربعة الأخرى، مما يسمح لانخفاض النشاط تراوت البحيرة. على أساس دبابة من قبل للدبابات، وسجلت كمية الطعام التي يتم تناولها من قبل تراوت البحيرة في كل يوم من التجربة. كان وزنه كل تراوت البحيرة في بداية ونهاية التجربة. تمت التضحية أربعة إلى تسعة تراوت البحيرة من كل من الدبابات ثمانية في بداية التجربة، وجميع سمك السلمون المرقط البحيرة 10 المتبقية في كل من الدبابات euthanأوتوماتيكية في نهاية التجربة. نحن مصممون تركيزات PCB 75 متجانسا في تراوت البحيرة في بداية التجربة، في تراوت البحيرة في نهاية التجربة، والرنجة في تغذية سمك السلمون المرقط البحيرة أثناء التجربة. وبناء على هذه القياسات، تم حساب γ لكل من PCB 75 متجانسا في كل من الدبابات ثمانية. يعني تم حساب γ لكل من 75 متجانسا PCB للتراوت البحيرة على حد سواء نشطة وغير نشطة. لأنه تم نسخ التجربة في ثماني دبابات، والخطأ المعياري حول يعني يمكن تقدير γ. نتائج من هذا النوع من التجربة مفيدة في نماذج تقييم المخاطر للتنبؤ المخاطر المستقبلية للإنسان والحياة البرية تناول الأسماك الملوثة تحت سيناريوهات مختلفة من التلوث البيئي.

أظهر بحيرة سمك السلمون المرقط كمية كبيرة من النمو خلال التجربة، كما تعني تراوت البحيرة الأولية تراوحت أوزان 694-907 غرام بينما تعني تراوت البحيرة النهائية تراوحت أوزان من 853 إلى 1،566 غرام (الجدول 1). متوسط ​​كمية الطعام المستهلكة من قبل تراوت البحيرة أثناء التج?...

Watch this Scientific Journal Video about Laboratory Estimation of Net Trophic Transfer Efficiencies of PCB Congeners to Lake Trout Salvelinus namaycush from Its Prey at JoVE.com

Laboratory Estimation of Net Trophic Transfer Efficiencies of PCB Congeners to Lake Trout Salvelinus namaycush from Its Prey

ويرد تقنية المختبرات لتقدير صافي كفاءة نقل الغذائية من ثنائي الفينيل متعدد الكلورة (PCB) متجانسا إلى الأسماك الآكلة للأسماك من فرائسها. لتحقيق أقصى قدر من قابلية تطبيق النتائج المخبرية إلى الميدان، ويجب أن تغذى الأسماك الآكلة للأسماك الأسماك الفريسة التي تؤكل عادة في هذا المجال.

تقدير مختبر صافي الغذائية الكفاءة نقل المتجانسات PCB إلى بحيرة سمك السلمون المرقط (<em&gt; Salvelinus namaycush</em&gt;) من فريسته

A technique for laboratory estimation of net trophic transfer efficiency (&#947;) of polychlorinated biphenyl (PCB) congeners to piscivorous fish from ...

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Laboratory Estimation of Net Trophic Transfer Efficiencies of PCB Congeners to Lake Trout (Salvelinus namaycush) from Its Prey

Laboratory-determined Phosphorus Flux from Lake Sediments as a Measure of Internal Phosphorus Loading

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Next-generation sequencing of environmental samples can be challenging because of the variable DNA quantity and quality in these samples. High quality DNA ...

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إزالة العناصر النزرة التي كتبها نحاسي أكسيد النانوية من اليورانيوم<em&gt; في الموقع</em&gt; استرداد التسييل المياه وتأثيره على بقاء الخلية

In situ recovery (ISR) is the predominant method of uranium extraction in the United States. During ISR, uranium is leached from an ore body and extracted ...

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محاكاة المختبر من الحديد (II) الغنية نظام الموجات المتقلبة عصر ما قبل الكمبري البحرية لاستكشاف نمو البكتيريا الضوئي

A conventional concept for the deposition of some Precambrian Banded Iron Formations (BIF) proceeds on the assumption that ferrous iron [Fe(II)] upwelling ...

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تطور ال<em&gt; ميتاريزيوم أنيسوبلياي</em&gt; باعتباره ميكوسكتيسيد: من العزلة إلى الأداء الميداني

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Procedures of Laboratory Fumigation for Pest Control with Nitric Oxide Gas

الإجراءات المختبرية التبخير للسيطرة على الآفات مع غاز أكسيد النيتريك

Nitric oxide (NO) is a newly discovered fumigant for postharvest pest control. This paper provides detailed protocols for conducting NO fumigation on ...

Adherence of Bacteria to Plant Surfaces Measured in the Laboratory

الانضمام للبكتيريا لزراعة الأسطح قياسها في المختبر

This manuscript describes a method to measure bacterial binding to axenic plant surfaces in the light microscope and through the use of viable cell ...

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