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.

ניסוי מעבדה .1 <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> השג את דגי הטרף להיות מוזן לדגים טורפים במהלך הניסוי. רצוי צריך להיות בשבי דג הטרף האלה בתחום, הקפוא, ומאוחסן בכ -30 C °. קחו למשל את פעילות דיג מסחרית כמקור פוטנציאלי לדגי הטרף. </li><li style=";text-align:right;direction:rtl"> לה...

<ol>
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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. 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עבור האומדנים מדויקים ביותר של γ, הנסיין חייב להיות מסוגל לעקוב אחר שתי כמות המזון ממוקמת בכל אחד מהטנקים וכמות מזון שלא נאכל בכל אחד מהטנקים במהלך הניסוי בצורה מדויקת. כדי להשיג זאת, הנסיין חייב להיות מסוגל להסיר את כל מזון שלא נאכל מהטנקים ולקבוע במדויק את משקלו. בנ?...

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 style="width:87px;">Lab Line Instruments</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="35">
			<td height="35" style="height:35px;width:259px;">Agilent 5973 GC/MS with chemical ionization</td>
			<td style="width:87px;">Agilent</td>
			<td style="width:119px;">5973N</td>
			<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

טכניקה להערכת מעבדה של יעילות נטו תזונתית העברה (γ) של biphenyl polychlorinated קרוב ב( PCB) לדגי piscivorous מהטרף שלהם מתוארת במסמך זה. במהלך ניסוי מעבדה 135 יום, האכלנו מנופח (Coregonus hoyi) שנתפס באגם מישיגן לטרוטה (namaycush Salvelinus) המשיך בשמונה טנקי מעבדה. המנופח הוא טרף טבעי עבור טרוטה. בארבעת הטנקים, קצב זרימה גבוה יחסית היה בשימוש על מנת להבטיח פעילות גבוהה יחסית על ידי טרוטה, ואילו קצב זרימה נמוך שימש בארבעה טנקים האחרים, המאפשר לפעילות טרוטה נמוכה. על בסיס טנק אחר טנק, כמות המזון נאכלה על ידי טרוטה בכל יום של הניסוי נרשמה. כל טרוטה נשקלה בהתחלה והסיום של הניסוי. ארבעה עד תשע טרוטה מכל אחד משמונת הטנקים הוקרבו בתחילת הניסוי, וכל פורל 10 האגם שנותר בכל אחד מהטנקים היו euthanized בסוף הניסוי. אנחנו נקבע ריכוזים של 75 קרובים בPCB בטרוטה בתחילת הניסוי, בטרוטה בסוף הניסוי, ובbloaters מוזנים לטרוטה במהלך הניסוי. בהתבסס על המדידות הללו, γ חושב שלכל אחד מן 75 קרובים בPCB בכל אחד משמונת הטנקים. אומר γ חושב שלכל אחד מן קרוב בPCB 75 לטרוטה שני פעילה ולא פעילה. בגלל הניסוי חזר על עצמו בשמונה טנקים, השגיאה סטנדרטית על משמעות γ יכול להיות מוערך. תוצאות מסוג זה של ניסוי שימושיות במודלים להערכת סיכון ללחזות את עתיד סיכון לבני אדם וחיות בר אכילת דגים מזוהמים בתרחישים שונים של זיהום סביבתי.

טרוטה הראתה כמות משמעותית של צמיחה במהלך הניסוי, כטרוטה הראשונית אומרת משקולות נעות 694-907 g כאשר טרוטה הסופית אומרת משקולות נעות בין 853 ל1,566 גר &#39;(טבלת 1). כמות המזון הממוצעת הנצרכת על ידי טרוטה במהלך הניסוי 135 היום נעה בין 641 ל2,649 גרם. אומר ריכוזי משלימתו PCB בטרוט...

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

טכניקה להערכת מעבדה של יעילות נטו תזונתית העברת biphenyl polychlorinated הקרוב ב( PCB) לדגי piscivorous מהטרף שלהם מוצגת. על מנת למקסם את תחולתה של תוצאות המעבדה לשדה, דגי piscivorous צריכים להיות מוזנים דגי טרף שנאכלים בדרך כלל בתחום.

הערכת מעבדה של יעילות העברה הנקי התזונתית של קרוב בPCB לאגם פורל (<em&gt; Salvelinus namaycush</em&gt;) מטרפו

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

נקבע מעבדה זרחן שטף מאגם המשקעים כמדד לטעינה הפנימית זרחן

Eutrophication is a water quality issue in lakes worldwide, and there is a critical need to identify and control nutrient sources. Internal phosphorus (P) ...

A Fish-feeding Laboratory Bioassay to Assess the Antipredatory Activity of Secondary Metabolites from the Tissues of Marine Organisms

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Marine chemical ecology is a young discipline, having emerged from the collaboration of natural products chemists and marine ecologists in the 1980s with ...

Automated Gel Size Selection to Improve the Quality of Next-generation Sequencing Libraries Prepared from Environmental Water Samples

בחירת גודל האוטומטי ג&#39;ל כדי לשפר את האיכות של ספריות רצף הדור הבא הוכן מדגימות סביבתיות מים

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

Removal of Trace Elements by Cupric Oxide Nanoparticles from Uranium In Situ Recovery Bleed Water and Its Effect on Cell Viability

Removal of Trace Elements by Cupric Oxide Nanoparticles from Uranium In Situ Recovery Bleed Water and Its Effect on Cell Viability

הסרת יסודות קורט ידי Cupric תחמוצת חלקיקים מאורניום<em&gt; באתר</em&gt; שחזור Bleed מים והשפעתה על כדאיויות תא

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 ...

Laboratory Simulation of an Iron(II)-rich Precambrian Marine Upwelling System to Explore the Growth of Photosynthetic Bacteria

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סימולצית מעבדה של הברזל (II) -rich Precambrian ימי גאות מערכת לחקור את הצמיחה של חיידקים פוטוסינתטיים

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

Development of Metarhizium anisopliae as a Mycoinsecticide: From Isolation to Field Performance

Development of Metarhizium anisopliae as a Mycoinsecticide: From Isolation to Field Performance

פיתוח של<em&gt; מטריציום anisopliae</em&gt; כמקוטלת חיידקים: מהבידוד לביצועי שדה

A major concern when developing commercial mycoinsecticides is the kill speed compared to that of chemical insecticides. Therefore, isolation and ...

Procedures of Laboratory Fumigation for Pest Control with Nitric Oxide Gas

תהליכי מעבדה ההדברה להדברה בגז תחמוצת החנקן

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

דבקותה של חיידקים לשתול משטחים הנמדדים במעבדה

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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Beneficial plant-microbe interactions offer a sustainable biological solution with the potential to boost low-input food and bioenergy production. A ...

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Sheet erosion is among the crucial drivers of soil degradation. Erosion is controlled by environmental factors and human activities, which often lead to ...