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THE INFLUENCE OF DIFFERENT FACTORS ON THE CONCENTRATION OF ELEMENTS IN HAIR OF HORSES

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Zbigniew Dobrzański at Wroclaw University of Environmental and Life Sciences
Zbigniew Dobrzański
Dominika Jankowska at University of Białystok
Dominika Jankowska
Wojciech Dobicki at Wroclaw University of Environmental and Life Sciences
Wojciech Dobicki
Robert Kupczyński at Wroclaw University of Environmental and Life Sciences
Robert Kupczyński
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ISAH 2005 - Warsaw, Poland
Vol 2
450
THE INFLUENCE OF DIFFERENT FACTORS ON THE
CONCENTRATION OF ELEMENTS IN HAIR OF HORSES
Zbigniew Dobrzanski, Dominika Jankowska, Wojciech Dobicki, Robert Kupczynski
Agricultural University of Wroclaw, Department of Animal Hygiene and Environment,
ul. Chelmonskiego 38 C, 51-630 Wroclaw, Poland
Key words: horse, hair, trace elements
Introduction
Anthropogenic pressure on natural environment causes many biogeochemical changes
in it. It is reflected by the changes in the chemical composition of animal organisms including
hair, milk, eggs, tissues and organs.
The analysis of trace elements and toxic metals content in hair and coat is used for
evaluation of health state, metabolic disorders and mineral maintenance of human and
animals. Sampling, storage and analysis of these samples are easier than in case of other
biological material [1, 3, 7, 8]. Hair analysis has been used to examine the exposure of horses
to such toxic heavy metals as lead and cadmium [7]. In recent years, research has been
conducted on the concentration of toxic elements and bioelements in horse hair with respect
to their sex, age, feeding season, physiological norms and interactions between the elements
[1, 3, 4, 5].
The aim of the present work was to compare the concentration of selected elements in
horse hair, depending on the type of mineral feed additives and season of the year. The horses
were kept in two different regions of Lower Silesia.
Material and methods
Clinically healthy horses, 16 mares, from two regions:
-industrial region of Walbrzych (SO Ksiaz) – horses of Silesian breed (group A, n=8),
-the region not affected directly by industry, mountain vicinity of Kowary – horses of sp
breed (group B, n=8) were the subjects of the present study.
The research was preformed in the season of hair changing from winter hair to the
summer one and from summer one to the winter one in the years 2004-2005. The animal
feeding, especially the mineral feed additives, were differentiated in both places:
Group A - feed dose in winter period: 4-6 kg of crushed oats, 4 kg of hay, straw (ad
lib.), 3g of Biogen K preparation (containing live lyophilized bacteria cultures 153.6 mln
JTK) and the mineral-vitamin-aminoacidic preparation in the form of chelate compounds
ISAH 2005 - Warsaw, Poland
Vol 2
451
(Fitmin). Feed dose in summer period: 30 kg of green forage, 3 kg of hay and Fetmin food
additive. Group B - in winter season the horses were administered 4 kg of oats grain, hay (ad
lib.), and in summer they fed only on the pasture (ad lib.) and were administered hay.
The horses were given water of constant mineral composition (tap water). Bay horses aged 4-
6 years were selected from each place. In each of the periods, the hair was taken from the
neck. The samples were cleaned and washed. After drying to the solid mass at the temperature
of 65°C, the samples were mineralized (wet mode) in nitric acid in a closed high pressure
microwave stove (CEM). The content of Cr, Cu, Ni, Cd, Pb and Zn was measured by flame
method of atomic absorption spectophotometry (AAS) using Varian SpectrAA 220 FS
apparatus. The results of the analyses were verified using the certified reference material
DOLT-2.
The results were statistically analyzed using Statgraphics ver. 5.0. software.
Results and discussion
The content of the tested elements in horse hair is presented in Table 1. No statistical
differences in the content of the examined elements in the horse hair were observed, both
between the periods of tests (summer, winter) and between the regions (group A, group B).
Only the content of Zn in winter horse hair in Group A was statistically higher (p<0.05) in
comparison to the content in the horse hair in Group B (122.64 and 112.63 mg/kg of dried
mass, respectively). The differences were the effect of using mineral-vitamin food additives in
feeding the horses of Group A. Positive correlation was observed between Pb and Cd (r=
0.35, p<0.05). Although the statistical differences between the test periods and the groups
were not present, some relations, especially connected with the season of the year, were
observed.
In the hair of horses of Group A, higher content of Cr, Cu, Ni and Zn was observed in
winter coat than in summer coat, the only opposite relation was observed in Cd concentration.
Different tendencies were observed in Cr, Cd, and Zn content in the test carried out on the
horses from Group B. The concentration of these elements was slightly higher in the summer
coat.
Average content of Cu, Ni, Cd and Zn during all test period were equal between the
groups (regions) which shows the lack of influence of environment and the lack of visible
influence of mineral composition of diet on the level of concentration of these elements in
horse hair. Higher content of Cr and Pb was observed in the hair of horses from Group B,
these differences, however, were not confirmed statistically.
ISAH 2005 - Warsaw, Poland
Vol 2
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Attempts have been made to use hair analysis as an indicator of the total content of
minerals, such as calcium and phosphorus and trace metals such as copper, molybdenum,
zinc, selenium and iron [2, 5, 8] in the body. Asano et al. [1] have not observed any
differences in the concentration of essential metals and toxic metals in the horse hair between
the mares and stallions. However, visible relations concerning the age, especially in the case
of toxic metals such as Cd, Hg and essential minerals such as Mn, Mo, Fe were observed.
The concentrations of Cd, and Cr obtained in own tests were close to the values given as
referential for racing horses [1]. The content of Zn, Cu, and Pb was slightly higher than the
limit of referential values [1]. Similar concentration was obtained in the tests carried out on a
large number of animals (106 horses) by Wichert at al. Low concentration of Pb in horse hair,
especially in Group A, was observed in own tests. In other tests, the values of this element
were higher [2] but very differentiated in respect to the region of the origin of the animals.
There are also some breed differences in the content of individual elements in horse hair [3].
The concentration of Cd and Pb in horse hair can be the result of the influence of the
season. The higher concentration of these elements in summer coat may indicate
environmental exposure [2, 6]. In own tests this relation was confirmed in the case of Cd.
Hair is a good indicator of organism’s mineral supply in Zn [5]. As it was presented in own
tests, mineral supplementations, especially during winter-feeding, causes relevant (p<0.05)
increase of Zn content in horse hair (Group A). Calcium surplus in diet influences the fall of
Zn content in the organism and the changes of Zn concentration in hair indicate the
antagonism of Zn and Ca in the processes of absorbing from alimentary canal [4]. However,
there are still uncertainties as to whether hair content is well correlated with whole body
levels and the validity of the approach in the horse remains to be confirmed [8].
Conclusions
Different environment and different mineral feed additives did not have a significant
influence on the levels of the tested elements in horse hair, only Zn concentration was higher
in the horses which in winter were given mineral-vitamin food additives (Group 1, SO Ksiaz).
The results obtained show seasonal influence on the levels of the tested elements in horse
hair. Higher concentrations of Cr and Pb were observed in the horses from Kowary region,
however the registered levels are toxicologically safe.
ISAH 2005 - Warsaw, Poland
Vol 2
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References
1. Asano R., Suzuki K., Otsuka T., Otsuka M., Sakurai H.: Concentrations of toxic metals and minerals in the
mane hair of healthy racing horses and their relation to age. J. Vet. Sci. 64, 2002, 607-610.
2. Ciesla A., Janiszewska J.: Cadmium and lead concentration in hair of halfbred horses in various breeding
centres and seasons of the year. Fol. Iuniv. Agric. Stetin. 194 Zootechnica, 23-30.
3. Ciesla A., Janiszewska J.: Porownanie poziomu wybranych pierwiastkow w surowicy krwi i siersci koni
wielkopolskich i konikow polskich. Zesz. Nauk. AR Szczecin. Zootechnika 35, 194, 177, 1997, 259-265.
4. Danek J., Wisniewski E., Krumrych W., Dabrowska J.: Wplyw nadmiaru wapnia w paszy na wskazniki
hematologiczne oraz biochemiczne w surowicy krwi i siersci ogierow. Medycyna Wet. 51, 1995, 544-547.
5. Danek J., Wisniewski E.: Wplyw niedoboru cynku w diecie na wskazniki hematologiczne, aktywnosc
fosfatazy zasadowej i stezenie bialka calkowitego w surowicy oraz na zawartosc cunku, miedzi i wapnia w
surowicy i siersci ogierow. Medycyna Wet. 48, 1992, 521-523.
6. Janiszewska J., Betlejewska-Kadela K.: Stezenie Mg, Zn, Mn i Co w siersci koni w zaleznosci od sezonu
zywieniowego. Medycyna wet. 49, 1993, 522-523.
7. Liu Z.P.: Lead poisoning combined with cadmium in sheep and horses in the vicinity of non-ferrous metal
smelters. Sci. Total Environ. 309, 2003, 117-126.
8. Wichert B., Frank T., Kienzle E.: Zinc, copper and selenium intake and status of horses in Bavaria. J. Nutr.
132, 2002, 1776-1777.
Table 1.The content of selected elements in horse hair (mg/kg dry mass,
x
±s)
Elements
Stable
and season Cr Cu Ni Cd Pb Zn
Group A -
summer 0.30±0.34 7.48±1.92 0.98±0.21 0.12±0.09 0.06±0.07 114.90±8.67
Group A -
winter 0.39±0.40 7.88±0.53 1.08±0.20 0.04±0.03 0.08±0.08 122.64±10.26a
Total 0.35±0.36 7.68±1.38 1.03±0.20 0.08±0.08 0.07±0.07 118.77±10.01
Group B -
summer 0.58±0.64 7.47±0.68 0.93±0.28 0.10±0.17 0.12±0.13 120.63±8.50
Group B -
winter 0.52±0.32 8.31±1.76 0.89±0.17 0.07±0.05 0.10±0.06 112.63±6.48a
Total 0.55±0.49 7.89±1.36 0.91±0.22 0.09±0.12 0.11±0.10 116.63±8.39
a – significant differences at p<0.05
... Evaluation of the concentrations of trace minerals can be an important tool when assessing individual or population health in free-ranging or stabled animals (Roug et al. 2015). Hair has been evaluated as an indicator of trace mineral and heavy metal status in livestock, and the reliability of hair as a measure of the mineral levels varies with animal species, geographic location, hair color, age and sex (Manson and Zlotkin 1985, Combs 1987, Janiszewska and Betlejewska-Kadela 1993, Asano et al. 2002, Wichert et al. 2002, Janiszewska and Ciesla 2002, Dobrzanski et al. 2005, Stachurska et al. 2011. To our best knowledge, research on the effects of diet and the maintenance system on morphology and elemental content of the hair of horses, excluding the impact of geographical location and breed, has not been assessed. ...
... Studies that assessed the elemental content in the hair of Wielkopolska horses depending on the seasons found that there were statistically significant differences in the levels of Cu, which we did not measure (Janiszewska and Betlejewska-Kadela 1993). Dobrzanski et al. (2005) did not observe any significant differences in the concentration of essential minerals in hair derived from two different breeds of horses, living in different environments and receiving different mineral feed additives. The concentration of heavy metals in the coat of horses kept in a stable-pasture and outdoor system are in most cases similar (Stachurska et al. 2011). ...
... Unlike blood, hair is stable biological material that is not affected by acute and transient factors (Dunnett 2001). However, the heavy metal content of horse hair has been shown to be affected by seasonal variation in a number of horse breeds (Janiszewska and Betlejewska-Kadela 1993, Ciesla and Janiszewska 1997, Dobrzanski et al. 2005). This could be explained by the time the horses spend on pastures, where they are exposed to atmospheric pollution. ...
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The objective of the present study was assessment of gender differences in hair trace element content in English Thoroughbred horses (North Caucasus, Russia) using ICP-DRC-MS and calculation of the reference values. Trace element content in mane hair of 190 stallions and 94 mares (3–7 years old) bred in North Caucasus (Russia) was assessed using inductively coupled plasma mass spectrometry. Mane hair Co, Cr, Mn, Li, Si, and Sr levels in mares exceeded those in stallions by 77%, 63%, 64%, 42%, 39%, and 64%, respectively. Hair Fe and Si content was nearly twofold higher in female horses as compared to the males. Only hair Zn content was 5% higher in stallions as compared to mares. In addition, mares were characterized by 63%, 65%, 29%, and 40% higher levels of As, Pb, Sn, and Ni levels in hair as compared to the respective values in stallions. In turn, hair Al and Hg were more than twofold higher in mares than in stallions. The reference intervals of mane hair content (μg/g) for Co (0.006–0.143), Cr (0.028–0.551), Cu (4.17–6.84), Fe (10.11–442.2), I (0.026–3.69), Mn (0.551–12.55), Se (0.108–0.714), Zn (97.43–167), Li (0.011–0.709), Ni (0.060–0.589), Si (0.665–29.12), V (0.006–0.584), Al (1.98–168.5), As (0.006–0.127), Cd (0.002–0.033), B (0.494–16.13), Pb (0.018–0.436), Sn (0.002–0.144), Sr (1.0–9.46), and Hg (0.0018–0.017) in the total cohort of horses were estimated using the American Society for Veterinary Clinical Pathology Quality Assurance and Laboratory Standard Guidelines. The reference intervals were also estimated for stallions and mares bred in North Caucasus (Russia) and may be used for interpretation of the results of hair trace element analysis in horses.
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... The herd of horses covered by the study were fed on bulky feed obtained from mountain meadows that were extensively exploited, which could affect the availability of bio-elements. Dobrzanski et al. (2005) obtained results of chromium concentration similar to ours (0.324±0.221mg/kg dry mass) from Silesian mares in the Herd of Książ Stallion. In the afore-mentioned studies, higher concentrations were noted in hair of half-bred noble mares, i.e., 0.55±0.49mg/kg ...
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Concentrations of Toxic Metals and Essential Minerals in the Mane Hair of Healthy Racing Horses and Their Relation to Age
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Concentrations of trace elements (As, Al, Pb, Cd, Hg, Se, Si, P, Na, K, Ca, Mg, Fe, Cu, Zn, Mn, Cr, Ni and Mn) in the mane hair obtained from 9 female and 15 male healthy racing Thoroughbred horses aged 2-5 years were analyzed by the inductively coupled plasma atomic emission spectrometry (ICP-AES) method. No significant differences between the female and male horses were observed in the mean concentrations of those minerals. Significantly positive correlations with age were observed in Cd (r=0.546, p<0.01) and Mo (r=0.733, p<0.001). Significantly negative correlations with age were observed in Hg (r= -0.726, p<0.001), Mn (r= -0.450, p<0.05) and Fe (r=-0.642, p<0.01). This reference range of trace elements in the mane hair of racing horses should be used to assess disease and the nutritional status in equine practice.
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The diagnosis of lead poisoning combined with cadmium in sheep and horses living on farmland in the vicinity of non-ferrous metal smelters in Baiyin of Gansu province in China was based on laboratory findings as well as clinical signs. The concentrations of lead, cadmium, copper and zinc in soils, water, forages, feed and blood, hair and tissues of affected sheep and horses were determined in the surroundings of the smelters in Baiyin and controls. Haematological values were also measured. The concentrations of these elements in soils, forages, water and feed were significantly higher than those in the control area (P<0.01). The contents of lead and cadmium were 9.3 and 690 times in forages, respectively, 10 and 35.6 times in feed. The concentrations of lead and cadmium in blood, hair and tissues of the affected sheep and horses were significantly higher than reference values and control animals (P<0.01). The occurrence of anaemia in affected animals belonged to a hypochromic and microcytic pattern. Lead and cadmium intake levels, estimated according to the ingestion rates of forages, illustrates that the apported lead and cadmium through the ingestion of vegetation growing in the closest sites to the smelters were approximately 6.0 mg Pb/kg body wt./day and 1.1 mg Cd/kg body wt./day in horses, 21.4 mg Pb/kg body wt./day and 4.0 mg Cd/kg body wt./day in sheep, surpassing the fatal dosages for horses of 1.7 mg Pb/kg body wt./day and for sheep of 4.4 mg Pb/kg body wt./day and 1.0 mg Cd/kg body wt./day. It is, therefore, suggested that the disease of sheep and horses in this region is caused by lead poisoning combined with cadmium, mainly due to environment heavy metal pollution by industrial activity. Meanwhile, as such levels of contamination in animal food and grain pose a significant potential risk to human health, these results have formed the basis for subsequent research on levels of metal contamination in human tissues from affected populations. Thus, it can be seen that knowledge of lead and cadmium concentrations in livestock in this region is important for assessing the effects of pollutants on domestic animals themselves and contaminant intakes by humans.
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Porownanie poziomu wybranych pierwiastkow w surowicy krwi i siersci koni wielkopolskich i konikow polskich
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Ciesla A., Janiszewska J.: Porownanie poziomu wybranych pierwiastkow w surowicy krwi i siersci koni wielkopolskich i konikow polskich. Zesz. Nauk. AR Szczecin. Zootechnika 35, 194, 177, 1997, 259-265.
Wplyw niedoboru cynku w diecie na wskazniki hematologiczne, aktywnosc fosfatazy zasadowej i stezenie bialka calkowitego w surowicy oraz na zawartosc cunku, miedzi i wapnia w surowicy i siersci ogierow
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Stezenie Mg, Zn, Mn i Co w siersci koni w zaleznosci od sezonu zywieniowego. Medycyna wet
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Wplyw nadmiaru wapnia w paszy na wskazniki hematologiczne oraz biochemiczne w surowicy krwi i siersci ogierow
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