Heavy Metals and Trace Elements in the Livers and Kidneys of Slaughtered Cattle, Sheep and Goats

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1 Originl Article Vol 10, No 6, November-December2016 Hevy Metls nd Trce Elements in the Livers nd Kidneys of Slughtered Cttle, Sheep nd Gots Behnz Bzrgni-Gilni* 1, Mohmdrez Pjohi-Almoti 1, Alisghr Bhri 2, Abs Ali Sri 1 Received: Accepted: ABSTRACT Bckground: This study ws performed to evlute the levels of hevy metls in the livers nd kidneys of cttle, sheep nd gots from mining region in the west of Irn. Methods: In this cross-sectionl study, 90 smples were collected from the livers nd kidneys of cttle (n=30), sheep (n=30) nd gots (n=30) from slughterhouse in Hmedn City, western Irn. Led, cdmium, mngnese, zinc, copper, nd iron concentrtions were nlyzed using Atomic Absorption Spectroscopy. Results: Led concentrtion exceeded the permissible limit in ll smples. Cdmium level ws within the permissible limit in most smples, except for the cttle nd sheep kidneys. Iron concentrtion ws norml in ll smples, except for sheep livers nd kidneys. The rest of the elements (mngnese, zinc nd copper) were within the sfe rnge. There were no sex nd gerelted significnt differences in metl concentrtions of cttle smples. The highest effects of ge nd sex were observed in sheep smples. Conclusion: The soil of these res contins high level of led nd cdmium, contminting the plnts, wter nd nimls of these regions; therefore, precise cre nd helth inspection of livestock in these res re recommended. Keywords: Environmentl Pollution, Hevy Metls, Liver, Kidney, Ruminnts. INTRODUCTION Animl tissues such s liver nd kidney re importnt for the humn diet, providing essentil nutrients for the body [1]. In mny Middle Est countries, viscerl orgns (e.g. liver nd kidney) re consumed s vluble nd pltble food products [2] nd in most countries, these products re offered s populr foods in mny resturnts [3]. Unfortuntely, viscerl orgns sometimes contin certin toxic compounds such s hevy metls. Cttle, got nd sheep flocks re usully seen grzing in contminted lnds, where the soil, grss, ir nd wter cn be contminted with hevy metls, entering the livestock tissues [4]. Nowdys, incresing popultion growth, mining, industriliztion, trnsporttion nd excessive utiliztion of nturl resources hve ugmented environmentl pollution [5]. Livers nd kidneys of livestock re responsible for detoxifiction of poisonous substnces entering the body; thus, they show higher concentrtions of these substnces IJT 2016 (6): 7-13 thn other orgns [1]. Over time, hevy metls cn ccumulte in the body nd become toxic or crcinogenic [6]. Unfortuntely, in mny countries, locl stndrds for metl levels in food products such s met nd internl orgns of nimls re missing. Furthermore, contminted nimls with high levels of toxic metls my not show ny pprent symptoms of disese nd pss helth inspection. The present study imed t evluting the levels of hevy metls (led, cdmium, mngnese, zinc, copper, nd iron) in the livers nd kidneys of cttle, got nd sheep from slughterhouse in Hmedn City, western Irn nd ssessing whether their ccumultion is relted to sex nd ge. MATERIALS AND METHODS Smples were digested using modified method [7]. All plstic nd glss continers were clened by soking in dilute HNO3 were rinsed in distilled wter nd then ir dried before use. 1. Deprtment of Food Hygiene nd Qulity Control, Bu-Ali Sin University, Hmedn, Irn. 2. Deprtment of Clinicl Sciences, Bu-Ali Sin University, Hmedn, Irn. *Corresponding Author: E-mil: b.bzrgni@bsu.c.ir

2 Behnz Bzrgni-Gilni et l Downloded from ijt.rkmu.c.ir t 0: on Mondy Jnury 14th 2019 [ DOI: /rkmu ] Collection of Smples Ninety smples ws collected from the livers nd kidneys of cttle (n=30), sheep (n=30) nd gots (n=30) from slughterhouse in Hmedn City, western Irn from December 2014 to Februry The smples were collected in clen polyethylene bgs in n icebox nd were trnsported to the lbortory for nlysis. The sex of the nimls ws recorded t the time of smpling (13 bulls nd 17 cows, 14 rms nd 16 ewes, nd 18 bucks nd 12 nnnies). Age dt were obtined nd used to ssign nimls to seprte ge groups. Ech species ws divided into two groups: under 3 yr old (young group) nd from 3 yr old (old group). There were 19 young nd 11 old cttle, 13 young nd 17 old sheep, nd 16 young nd 14 old gots. Preprtion of Smples In the lbortory, smples were immeditely dissected using stinless steel dissection instrument. Approximtely, 1g wet weight of met from ech smple ws dissected nd wshed with distilled wter. The tissue smples were dried in n oven t 105 C for 24 h. Then, the smples were pulverized into powder by grinder. Approximtely, 0.5 g of ech smple ws digested by dding 6 ml of nitric cid nd 1 ml of hydrogen peroxide (nlyticl grde) in digestion tube. Digestion ws performed in n electric heter under chemicl hood for 25 min. After digestion, smples were cooled nd the resulting solutions were filtered through Whtmn No. 41 filter pper into 10 ml screw-cpped polypropylene tubes nd the liquid were diluted to the volume of 10 ml with distilled wter. Determintion of Hevy Metls Hevy metls concentrtions were ssessed using Atomic Absorption Spectroscopy (A.A.S) (Spectr AA 220, Vrin). For ech hevy metl, there ws specific hollow cthode lmp nd the mchine ws set t prticulr wvelength for the metl to be nlyzed. The content of hevy metls in the ssessed tissues ws expressed in mg/kg of fresh mss. Sttisticl Anlysis Sttisticl nlysis of the dt ws conducted using SPSS softwre (IBM SPSS sttistics 21). Tukey nd independent-smple t- test with significnce vlue smller thn 0.05 (P<0.05) were used to compre the differences mong men vlues. RESULTS Men nd stndrd errors of hevy metl concentrtions in the livers nd kidneys of cttle, sheep nd got re shown in Tble 1. Tbles 2 nd 3 present the effect of sex on the hevy metl content in the livers nd kidneys. Tbles 4 nd 5 show ge effect. Tble 1. Men concentrtions (mg/kg) nd stndrd errors of hevy metls in the livers nd kidneys of cttle, sheep nd gots. Hevy metl Orgn N Cttle Sheep Got Pb Liver ± 3.30 A ± 5.17 A 1.69 ± 0.13 Bb Kidney ± 3.39 A ± 4.62 Ab 2.48 ± 0.17 Ac Mn Liver ± 0.19 A 6.06 ± 0.39 A 5.37 ± 0.32 A Kidney ± 0.11 Bb 3.10 ± 0.19 Bb 3.56 ± 0.18 B Cd Liver ± 0.02 B 0.21± 0.4 B 0.01 ± Bb Kidney ± 0.13 Ab 1.93 ± 0.41 A 0.33 ± 0.06 Ab Zn Liver ± 5.34 A ± 5.11 A ± 5.22 A Kidney ± 6.44 A ± 5.05 A ± 5.25 A Cu Liver ± 8.75 Ab ± A 27.93±10.90 Ac Kidney ± 0.57 B ± 0.83 B 7.11±1.49 Ab Fe Liver ± 8.42 Ab ± A ± 8.38 Ab Kidney ± 6.97 Ab ± A ± 9.01 Ab Mens within the sme row (, b, c) nd the sme column (A, B) with different letters re significntly different (P<0.05). 8 Vol 10, No 6, November-December 2016;

3 Hevy Metls nd Trce Elements in the Livers nd Downloded from ijt.rkmu.c.ir t 0: on Mondy Jnury 14th 2019 [ DOI: /rkmu ] Tble 2. Men concentrtions (mg/kg) nd stndrd errors of hevy metls in the livers of mle nd femle cttle, sheep nd gots. Hevy metl Sex N Cttle (liver) N Sheep N Got Pb Mle ±5.24 A ±10.22 A ±0.15 Ab Mn Femle ±4.27 A ±4.60 B ±0.17 A Mle ±0.29 A ±1.14 A ±0.33 A Femle ±0.26 A ±0.29 A ±0.65 A Cd Mle ±0.03 A ±0.04 Ab ± Ab Femle ±0.02 A ±0.06 A ±0.02 A Zn Mle ±6.77 A ±10.25 B ±6.01 A Cu Femle ±8.07 A ±4.29 A ±9.37 A Mle ±11.85 A ±19.83 Bb ±10.33 Ab Femle ±12.68 Ab ±7.49 A ±47.26 Ab Fe Mle ±14.66 A ±26.07 B ±8.13 A Femle ±10.10 Ab ±21 A ±29.30 Bb Mens within the sme row (, b, c) nd the sme column (A, B) with different letters re significntly Tble 3. Men concentrtions (mg/kg) nd stndrd errors of hevy metls in the kidneys of mle nd femle cttle, sheep nd gots. Hevy metl Sex N Cttle (kidney) N Sheep N Got Pb Mle ±4.76 A ±11.04 A ±0.20 Ab Femle ±4.86 A ±4.62 Ab ±0.4 Ab Mn Mle ±0.20 A ±0.77 A ±0.21 A Cd Femle ±0.14 Ab ±0.10 Ab ±0.37 A Mle ±0.27 A ±0.18 Ab ±0. 05 Bb Femle ±0.11 A ±0.50 A ±0.27 A Zn Mle ±7.59 A ±12.13 A ±5.59 A Femle ±9.97 A ±5.26 A ±10.29 A Cu Mle Femle ±0.66 A 12.20±0.81 Ab ±0.63 A 12.74±1.03 A ±1.67 A 7.34±3.81 Ab Fe Mle ±10.75 A ±18.12 B ±10.25 A Femle ±9.44 Ab ±11.62 A ±13.66 Ab Mens within the sme row (, b, c) nd the sme column (A, B) with different letters re significntly Tble 4. Men concentrtions (mg/kg) nd stndrd errors of hevy metls in the livers of younger nd older cttle, sheep nd gots. Hevy metl Age N Cttle (liver) N Sheep N Got Pb < ±4.05 Ab ±10.22 A ±0.15 Ac ±5.95 A ±4.60 B ±0.24 A Mn < ±0.28 A ±1.14 A ±0.33 B ±0.20 A ±0.29 A ±0.55 A Cd < ±0.02 A 0.15±0.03 A ±0.04 Ab 0.24±0.06 A ± Ab 0.03±0.03 A Zn < ±5.55 A ±10.25 B ±6.02 A ±11.64 A ±4.29 A ±1.97 A Cu < ±9.49 A ±19.83 Bb ±11.90 Ab Fe 3 < ±17.09 Ab ±10.92 A ±7.51 A ±26.07 B ±32.29 Ab ±8.38 A ±13.63 Ab ±21.00 A ±27.34 Ab Mens within the sme row (, b, c) nd the sme column (A, B) with different letters re significntly Vol 10, No 6, November-December2016 9

4 Behnz Bzrgni-Gilni et l Downloded from ijt.rkmu.c.ir t 0: on Mondy Jnury 14th 2019 [ DOI: /rkmu ] Tble 5. Men concentrtions (mg/kg) nd stndrd errors of hevy metls in the kidneys of younger nd older cttle, sheep nd gots. Hevy metl Age N Cttle (Kidney) N Sheep N Got Pb < ±3.89 A ±11.04 A ±0.20 Ab ±6.69 A ±4.62 Ab ±0.41 Ab Mn < ±0.16 A ±0.77 A ±0.21 A ±0.16 A ±0.10 A ±0.08 A Cd < ±0.19 A ±0.18 Ab ±0. 05 Ab ±0.11 A ±0.50 A ±0.29 A Zn < ±7.56 A ±12.13 A ±4.66 A ±12.61 A ±5.26 A ±26.74 A Cu < ±0.70 A ±0.63 Ab ±1.62 Ab ±0.79 A ±1.03 A ±4.56 A Fe < ±8.85 A ±18.12 B ±9.89 A ±11.76 Ab ±11.62 A ±26.22 Ab Mens within the sme row (, b, c) nd the sme column (A, B) with different letters re significntly DISCUSSION Led Tble 1 presents the results of led concentrtion in the livers nd kidneys of ll ssessed species. The led ws present in ll smples. The concentrtion of led ws higher in the cttle thn the sheep nd gots. Led concentrtion in ll specimens ws higher thn the permissible limit (>1 ppm) [8]. Other reserchers reported such contmintion in the in the livers nd kidney of cttle, beef, mutton, got, sheep, bufflo nd chicken in other regions s well [9,3]. There ws no significnt difference in the led concentrtion between mle nd femle species, except for the liver of mle sheep tht contined significntly (P< 0.05) higher led levels thn those of femle sheep (Tbles 2 nd 3). Age fctor in led level followed this pttern s well nd only the liver of young sheep showed significnt (P< 0.05) difference with old ones. Similr results were reported s for deer [10]. However, some uthors found ge nd sex-relted differences in nimls [9]. Cdmium Cdmium ws observed in ll smples (Tble 1). The highest concentrtion of cdmium ws in the sheep. The kidney of sheep (1.93 mg/ml) nd the liver of got (0.01 mg/ml) hd the highest nd lowest cdmium concentrtions, respectively. Except for the cttle (0.93 mg/ml) nd sheep kidney (1.93 mg/ml), cdmium concentrtion in ll species ws lower thn the permissible limit (< 0.5 ppm) [11]. Cdmium levels in niml kidneys were significntly higher thn their livers (P< 0.05) (Tble 1). This could be due to the excretory function of kidneys. High levels of led nd cdmium in these smples cn be correlted to the existence of led nd cdmium mines in this re [12]. This region includes prts of Mlyer, Tuyserkn nd Asdbd cities, locted round Hmedn City (Fig.1). Therefore, considerble mounts of led nd cdmium exist in the soil of these res tht could enter into frm niml feeds nd tissues. According to Tble 2 nd 3, there ws no significnt difference in cdmium concentrtion between mle nd femle species, except for the kidney of femle got tht contined significntly (P< 0.05) higher levels of cdmium thn those of mle gots. There ws lso no significnt difference in cdmium concentrtion between old nd young nimls of ll species (Tbles 4 nd 5). Khn et l. reported no sex nd ge-relted differences in cdmium concentrtions in livers nd kidneys of the studied nimls [10], but severl studies hve reported ge nd sex differences in cdmium concentrtion of cttle, sheep nd gots [9,13]. Figure1. Ares with high numbers of hevy metl mining opertions. 10 Vol 10, No 6, November-December 2016;

5 Hevy Metls nd Trce Elements in the Livers nd Mngnese The min orgn contining mngnese ccumultion ws the liver with sttisticlly significnt (P<0.05) higher levels thn the kidneys (Tble 1). All tested nimls hd liver mngnese concentrtions below ccepted toxic levels (23 mg/kg wet weight) nd bove those described s deficient (<1 mg/kg wet weight). Although mngnese cn exhibit toxic effects in higher concentrtions, it is often considered one of the lest toxic trce elements in mmmls. In fct, homeosttic mechnisms keep tissue mngnese levels within limited rnge [14].The men concentrtions of mngnese in the livers nd kidneys of mles nd femles re shown in Tble 2 nd 3, respectively. Mngnese concentrtions in the liver were higher in femles thn mles; wheres, the results were similr in both groups for the kidney. This difference ws probbly the result of the liver being the min tissue for mngnese ccumultion [14]. There is little informtion on the influence of sex on mngnese ccumultion. Similr results in gots is reported [14]. Tble 4 nd 5 show men concentrtions of mngnese in the livers nd kidneys of younger nd older nimls. According to the results, mngnese level in livers nd kidneys of older cses ws slightly, but insignificntly higher thn the younger ones, except for the got livers. In greement with our findings, severl uthors recorded no ge differences in mngnese concentrtions in deer, domestic nd lbortory nimls [10,15]. Zinc Tble 1 presents the results of zinc concentrtion in the livers nd kidneys of our cses. The highest zinc level ( mg/kg) ws found in the liver of the sheep nd the lowest level (87.94 mg/kg) ws in the kidneys of the cttle. Zinc predominntly ccumultes in the liver nd then the kidney. Previous reserchers described similr pttern of zinc ccumultion in their studies [16, 17]. All vlues in our studied smples were below the permissible limit (<150 ppm), set by Austrlin nd New Zelnd Food Authority (ANZFA) [8]. Low concentrtion of zinc my be ttributed to zinc deficient frm soils. Perhps, this is one of the resons for low tissue content of zinc. Zinc is controlled by precise homeosttic mechnisms for gstrointestinl bsorption nd excretion; consequently, it hs little vrition in concentrtion. No significnt difference ws observed in zinc levels of liver nd kidney between studied species. According to Tbles 2 nd 3, there ws no significnt effect of sex on zinc concentrtions in the livers nd kidneys of ll species, except for the sheep liver. The zinc level of liver in femle sheep ws significntly (P< 0.05) higher thn tht of mle livers. A similr pttern ws observed for ge fctor (Tble 4 nd 5). Only the zinc level of liver in older sheep ws significntly (P< 0.05) higher thn the younger ones. These results were in greement with the findings regrding sex nd ge fctors on zinc levels in livers nd kidneys of nimls in previous studies [14,18]. Copper Copper concentrtions in the tissues of different species re shown in Tble 1. The highest copper level ( mg/kg) ws found in the sheep liver, while its lowest level (7.11mg/kg) ws reported for the got kidney. Copper concentrtions in ll smples were lower thn the permissible limit of 200 ppm [8]. Copper level in liver smples ws significntly higher thn kidney smples in ll species (P< 0.05). Liver ws the min orgn contining copper, followed by the kidney, muscle, nd blood, concurs with previous studies [14,19]. According to metl richness nd totl rnk score, orgns hd the following order: liver > kidneys > hert > lungs > muscles. The livers nd kidneys re trget tissues for monitoring metl contmintion in nimls becuse both orgns re responsible for removing toxic metls from the body [3]. Furthermore, livers nd kidneys of the sheep contined the highest (P< 0.05) copper level mong the smples, followed by cttle nd gots. Ruminnts, prticulrly the sheep, hve higher potentils for copper ccumultion in their liver thn other species nd re more susceptible to copper toxicity [14]. According to Tbles 2 nd 3, sex did not ffect copper ccumultion in the livers nd kidneys of cttle nd gots [10,14]; wheres the liver of femle sheep contined significntly (P< 0.05) higher copper levels thn the mle sheep. Age effect ws similr to sex. Copper level in the liver of older sheep ws significntly (P < 0.05) higher thn the younger ones (Tbles 4 nd 5). Other studies reported no ge dependence of copper concentrtion in deer, domestic nd lbortory nimls [15]. Vol 10, No 6, November-December

6 Iron Iron concentrtions re summrized in Tble 1. The highest concentrtion ( mg/kg) ws found in the sheep livers while the lowest ( mg/kg) concentrtion ws observed in cttle's liver. The permissible limit of iron in food is generlly mg/kg [8], but in sheep livers nd kidneys, it exceeded this rnge. Unlike sheep, iron ccumulted preferentilly in the kidneys nd then the livers of the cttle nd gots. A similr pttern of ccumultion ws reported by Flndysz [2]. In contrst, Erdogn et l. found higher iron ccumultion in the liver thn in the kidney [20]. Iron levels in the livers nd kidneys of mles nd femles were different for ll species (Tbles 2 nd 3). No significnt difference ws seen between the livers nd kidneys of mle nd femle cttle, wheres the livers nd kidneys of femle sheep contined significntly (P< 0.05) higher iron levels thn the mle sheep. Iron concentrtion of liver in mle gots ws significntly (P<0.05) higher thn femle gots, but there ws no significnt difference between mle nd femle gots kidneys. There is not enough dt regrding the effect of sex on iron ccumultion in nimls. Khn et l. reported significntly higher iron concentrtions in the livers nd kidneys of mle gots [21], wheres contrsting results hve been reported for the cttle [14]. Tbles 4 nd 5 present the effects of ge on iron levels in different species. Cttle nd gots did not show ny significnt differences in iron concentrtions of livers nd kidneys of younger nd older nimls, wheres the livers nd kidneys of older sheep contined significntly (P< 0.05) higher iron level thn the younger sheep. CONCLUSION The soil of these res contins high level of led nd cdmium, contminting the plnts, wter nd nimls of these regions; therefore, precise cre nd helth inspection of livestock in these res re recommended. The effect of both sex nd ge on the exposure to hevy metls hs been well documented nd it hs been proven how they ffect levels of metls. Detiled investigtions re required to identify the resons of these findings. ACKNOWLEDGMENT Behnz Bzrgni-Gilni et l This study ws crried out in the Fculty of Veterinry Science, Bu-Ali Sin University of Hmedn, Irn. The uthors declre tht there is no conflict of interests. REFERENCES 1. Khlfll F, Abdel-Atty N, Mrim A, Omim I, Rofid B. Assessment of hevy metl residues in retil met nd offls. Am Sci 2015; 11: Flndysz J. Some toxic nd essentil trce metls in cttle from the northern prt of Polnd. Sci Totl Environ 1993; 136: EI-Slm NMA, Ahmd S, Bsir A, Ris AK, Bibi A, Ullh R, et l. Distribution of Hevy Metls in the Liver, Kidney, Hert, Pncres nd Met of Cow, Bufflo, Got, Sheep nd Chicken from Koht mrket Pkistn. Life Sci 2013; 10: Ihedioh J, Okoye C. Cdmium nd led levels in muscle nd edible offl of cow rered in Nigeri. Bull Environ Contm Toxicol 2012; 88: Ybe J, Nkym SM, Ikenk Y, Muzndu K, Ishizuk M, Umemur T. Uptke of led, cdmium, nd other metls in the liver nd kidneys of cttle ner led zinc mine in Kbwe, Zmbi. Environ Toxicol Chem 2011; 30: Demirezen D, Uruç K. Comprtive study of trce elements in certin fish, met nd met products. Met Sci 2006; 74: Akoto O, Bortey-Sm N, Nkym S, Ikenk Y, Bidoo E, Yohnnes YB, et l. Distribution of hevy metls in orgns of sheep nd got rered in Obusi: A gold mining town in Ghn. Int J Environ Sci Toxicol 2014; 2: Authority ANZF. Sfe food Austrli: guide to the Food Sfety Stndrds: Austrli New Zelnd Food Authority 2001; 12: Drwish W, Hussein M, El-Desoky K, Ikenk Y, Nkym S, Mizukw H, et l. Incidence nd public helth risk ssessment of toxic metl residues (cdmium nd led) in Egyptin cttle nd sheep mets. Int Food Res J 2015; 22: Khn A, Diffy B, Bridges E, Mielke H. Cdmium nd other hevy metls in the livers of white-tiled deer in Albm. Smll Ruminnt Res 1995; 18: FAO/WHO RotnSotCCoFAC, ALINORM 01/12, Beijing, Chin, Mrch. Joint FAO/WHO Food Stndrd Progrmme, Codex Alimentrius Commission, 24th Session, 2 7 July, Genev, Switzerlnd) Nouri J, Lorestni B, Yousefi N, Khorsni N, Hsni A, Seif F, et l. Phytoremedition potentil of ntive plnts grown in the vicinity of Ahngrn led zinc mine (Hmedn, Irn). Environ Erth Sci 2011; 62: Vol 10, No 6, November-December 2016;

7 Hevy Metls nd Trce Elements in the Livers nd 13. Rhimi E, Rokni N. Mesurement of cdmium residues in muscle, liver nd kidney of cttle slughtered in Isfhn bttoir using grfite furnce tomic bsorption spectrometry (GFAAS): preliminry study. Irn J Vet Res 2008; 9: Mirnd M, Alonso ML, Benedito JL. Copper, zinc, iron, nd mngnese ccumultion in cttle from Asturis (northern Spin). Biol Trce Elem Res 2006; 109: Underwood E. Trce elements in humn nd niml nutrition: Elsevier; Frmer AA, Frmer AM. Concentrtions of cdmium, led nd zinc in livestock feed nd orgns round metl production centre in estern Kzkhstn. Sci Totl Environ 2000; 257: Alonso ML, Montñ FP, Mirnd M, Cstillo C, Hernández J, Benedito JL. Interctions between toxic (As, Cd, Hg nd Pb) nd nutritionl essentil (C, Co, Cr, Cu, Fe, Mn, Mo, Ni, Se, Zn) elements in the tissues of cttle from NW Spin. BioMetls 2004; 17: Shrifi K. A survey on heptic nd renl trce elements sttus of sheep nd gots in Zrrinshhr region, Isfhn, Irn: n bttoir study. Irn J Vet Sci Tech 2014; 6: Swileh K, Abdulkhliq A, Hussein R, Mtni M. Distribution of toxic metls in orgns of locl cttle, sheep, got nd poultry from the West Bnk, Plestinin Authority. Bull Environ Contm Toxicol 2009; 83: Erdogn S, Celik S, Erdogn Z. Sesonl nd loctionl effects on serum, milk, liver nd kidney chromium, mngnese, copper, zinc, nd iron concentrtions of diry cows. Biol Trce Elem Res 2004; 98: Khn A, Diffy B, Forester D, Thompson S, Mielke H. Trce element concentrtions in tissues of gots from Albm. Vet Hum Toxicol 1995b; 37: Vol 10, No 6, November-December