Electronic Journal of Polish Agricultural Universities (EJPAU) founded by all Polish Agriculture Universities presents original papers and review articles relevant to all aspects of agricultural sciences. It is target for persons working both in science and industry,regulatory agencies or teaching in agricultural sector. Covered by IFIS Publishing (Food Science and Technology Abstracts), ELSEVIER Science - Food Science and Technology Program, CAS USA (Chemical Abstracts), CABI Publishing UK and ALPSP (Association of Learned and Professional Society Publisher - full membership). Presented in the Master List of Thomson ISI.
2010
Volume 13
Issue 1
Topic:
Animal Husbandry
ELECTRONIC
JOURNAL OF
POLISH
AGRICULTURAL
UNIVERSITIES
Szulc T. , Szurko J. , Wajda S. , Zielak-Steciwko A. , Newlacil I. , Demkowicz M. 2010. EFFICIENCY OF DRIED DISTILLERS GRAIN WITH SOLUBLES (DDGS) FEEDING IN YOUNG POLISH HOLSTEIN – FRIESIAN BULLS, EJPAU 13(1), #04.
Available Online: http://www.ejpau.media.pl/volume13/issue1/art-04.html

EFFICIENCY OF DRIED DISTILLERS GRAIN WITH SOLUBLES (DDGS) FEEDING IN YOUNG POLISH HOLSTEIN – FRIESIAN BULLS

Tadeusz Szulc1, Jarosław Szurko2, Stanisław Wajda3, Anna Zielak-Steciwko1, Irmina Newlacil1, Monika Demkowicz1
1 Institute of Animal Breeding, Wrocław University of Environmental and Life Sciences, Poland
2 Pol-Lean Sp. z o. o., Łosice, Poland
3 Department of Commodity Science and Animal Raw Material Proce, University of Warmia and Mazury in Olsztyn, Poland

 

ABSTRACT

Two stage experimental fattening was conducted on 64 young Polish Holstein-Friesian bulls of black and white type. Trial group was fed with concentrate containing 23.5% of corn dried distillers grain with solubles (DDGS) from 250 to 400-420 kg body weight, and 13.5% DDGS in finishing stage up to 570 kg body weight. The effect of extracted rapeseed meal replacing with corn DDGS on performance, carcass characteristics and fatty acid profile of intramuscular fat in muscullus longissimus dorsi was determined. Dried distillers grain with solubles supplementation caused significant (228 g) increase of average daily gain (ADG) in the first stage of experiment. Feed conversion rate (FCR, gain: feed) in trial group was 0.036 kg higher in the first, and 0.007 kg lower in the second stage of experiment comparing to the control group. Improved ADG and FCR in the first stage involved the 22 days decrease of experimental fattening period. Carcass dissection results and prime cuts percentage did not differ between trial and control group in none of fattening periods. Introduction of corn dried distiller grain with solubles into feed concentrate indicated an improvement of fatty acid composition, including increased level of C18:2 fatty acid in intramuscular fat.

Key words: young bulls, fattening, DDGS, slaughter value, dissection, fatty acids.

INTRODUCTION

An intensive development of bio-fuel industry causes an increased production of ethanol and its by-products. One of these products is dried distillers grain with solubles (DDGS) which is made of two dried post fermentation fractions. Processing of 100 kg of corn grain provides 40.2 l of ethanol, and 32.3 kg of DDGS [13]. This generates a necessity of utilization of this by-product. Dried distillers grain can be used as feed component in animal nutrition. It consists of non-fermentative corn grain fractions – protein, fat and fiber which are three-fold more concentrated than in raw corn grain [14]. Moreover, it contains yeasts which are a source of protein of high biological value and vitamins. Corn DDGS usually contains 20–30% of crude protein, of which about 50–55% is bypass protein [7,15]. Most of the energy contained in dried distillers grain comes from fat and fiber. This effects in a reduction of the risk of acidosis, when is fed in higher amounts [12]. Low structural value of this fiber can be increased by an addition of hay or straw [8]. DDGS is a valuable source of unsaturated fatty acids, which are up to 80% of total fatty acid amount. Chemical composition of distillers grain may be various though, and depends mostly on the quality of the grain and the bio-fuel production process.

It has been estimated that in 2010 in European Union 6.3 billion liters of ethanol will be produced [18]. That would give 5.06 billion tons of DDGS if made from corn only. In the USA over 80% of this by-product is utilized as a feed component for cattle, of which 45% as feed for beef cattle [17]. In beef animal nutrition, corn DDGS can provide up to 40% of feed dry matter, which is twice as much as can be used in dairy cattle feeding [11,12].

Objective
The aim of the study was to analyze the efficiency of young slaughter bulls feeding with concentrate containing corn dried distillers grain with solubles, and to determine the effect of  extracted rapeseed meal replacement with corn DDGS on performance, carcass characteristics and fatty acid profile of intramuscular fat in muscullus longissimus dorsi.

MATERIAL AND METHODS

The experiment was conducted on 64 young Polish Holstein-Friesian bulls of black and white type. Animals for this study were selected into groups according their body weight. The trial group numbered 25, and the control one 39 bulls. During the experiment one bull from each group was culled because of  their health condition. From 105 to 220–240 kg body weight all animals were fed with concentrate for calves (ad libitum) and meadow hay (about 1–1.5 kg per calf). Experimental, two stage, fattening was conducted from 250 to 570 kg body weight. Animals were intensively fed using four different concentrates. Composition of feed was dependent on a group type (trial or control) and a stage of the experiment.

Stage I (from 250 to 400–420 kg BW)
The control group was fed with concentrate I containing: 32.0% corn, 20.0% mixed wheat feed, 24.0% barley, 5.3% wheat bran, 16.0% extracted rape meal, 0.5% NaCl, 1.7% chalk and 0.5% premix. Chemical composition of concentrate I: dry matter – 90.19%, crude ash – 5.80%, crude protein – 16.40%, crude fiber – 6.49%, crude fat – 4.44%.

The trial group at that time was fed with concentrate DDGS-I containing: 30.5% corn, 18.0% mixed wheat feed, 20.0% barley, 5.3% wheat bran, 23.5% DDGS, 0.5% NaCl, 1.7% chalk and 0.5% premix. Chemical composition of concentrate DDGS-I: dry matter – 89.19%, crude ash – 5.89%, crude protein – 16.15%, crude fiber – 5.58%, crude fat – 5.28%.

Stage II – finishing (from 400–420 to 570 kg BW)
In finishing period all bulls were fed with low protein concentrates. The control group was fed with concentrate II containing: 33.0% corn, 23.0% mixed wheat feed, 27.0% barley, 5.3% wheat bran, 9.0% extracted rapeseed meal, 0.5% NaCl, 1.7% chalk and 0.5% premix. Chemical composition of concentrate I: dry matter – 89.36%, crude ash – 4.43%, crude protein – 13.29%, crude fiber – 6.60%, crude fat – 315%.

The trial group was fed with concentrate DDGS-II containing: 32.0% corn, 23.0% mixed wheat feed, 25.7% barley, 5.3% wheat bran, 11.3% DDGS, 0.5% NaCl, 1.7% chalk and 0.5% premix. Chemical composition of concentrate DDGS-I: dry matter – 90.55%, crude ash – 4.54%, crude protein – 12.81%, crude fiber – 5.07%, crude fat – 3.62%.
Chemical composition of used corn dried distillers grain with solubles: dry matter – 93.30%, crude ash – 5.26%, crude protein – 24.31%, crude fiber – 7.45%, crude fat – 10.45%.

Animals were fed according to the schedule. The right amount of concentrate was measured out every day for each group. About 1.5 kg of straw was given per each animal. Approximate diets for steers are shown in Table 1. Groups were held in boxes with straw bedding, so that the animals could have adjusted the amount of straw intaken. After reaching 570 kg body weight animals were slaughtered and carcasses dissection was conducted. Fatty acid composition of intramuscular fat was  determined using gas chromatography method.

Table 1. Nutrition scheme – diets for bulls during fattening (presumed daily gain 1100–1300 g per day)

Body weight (kg)

Concentrate (kg)

Hay + straw(kg)

Body weight
(kg)

Concentrate (kg)

Hay + straw(kg)

200–250

4.3

1.2

400-450

6.7

1.6

250-300

4.9

1.4

450–500

7.4

1.8

300-350

5.5

1.4

500-550

8.1

1.8

350-400

6.1

1.6

550-600

8.9

1.8

Slaughter and cutting
After the slaughter, half carcasses were weighted and placed in a cold store in the temperature of about 0–4°C. After 48 hours they were weighted again. After that, the right side (without a tail) was cut using the method required by a foreign contractor (UK). Following cuts were included: shoulder, chuck, fore ribs, ribs, plate with novel, brisket, sirloin, round, lion, flank, fore shank and hind shank. From chuck, fore ribs, ribs, loin and round fat was not removed in this cutting method.

Following parameters were determined: average daily gain (ADG), days of feed (DF), feed conversion ratio (FCR, gain: feed), meat in cuts (kg, %), tissue percentage, dressing percentage, selected fatty acid percentage, saturated, mono-unsaturated and poly-unsaturated fatty acid amount (SFA, MUFA, PUFA).
The obtained data were analyzed using Statistica 6.1 software. One factor analysis of variance was conducted. Significant differences between groups were defined with Duncan test.

RESULTS

The results of the analysis show similar and high average daily gain in both groups (about 1400 g) in the first fattening period from 105 to 250 kg body weight. In the first stage of the experiment (250–400 kg BW), an average daily gain differed between groups, with 1146 g and 1374 g respectively in control and trial group. Animals fed with DDGS-I concentrate were gaining 228g per day more (close to 20% more) and the difference was significant (Table 2). Also the FCR was higher in the trial group in the first stage of the experiment and differed between groups by 0.036. This indicates that introducing of dried distiller grain with solubles into concentrate was highly effective in this stage of fattening. In finishing period (from 400 to 570 kg BW) an average daily gain was on the same level in both groups and was 1179 g and 1181 g, respectively, in the control and trial group. At this stage, FCR seemed to be lower in animals fed with DDGS (about 0.007).

Table 2. Performance results of steers' from 106 to 570 kg body weight

Trait

BW (kg)

control group

trial group

sd

sd

ADG in body weight ranges (g)

106–250

1400

24

1387

23

251–400

1146a

28

1374b

28

401–570

1179

26

1181

30

ADG (g):
whole fattening
experiment

         

106–570

1242a

26

1314b

27

250–570

1162a

27

1277b

29

DF  in body weight ranges

106–250

102.8

2.31

103.8

2.25

251–400

130.9a

2.76

109.2b

2.75

401–570

144.2

2.58

143.9

2.35

DF:
whole fattening
experiment

         

106–570

377.9

2.54

356.9

2.65

250–570

275.1

2.67

253.1

2.55

FCR in body weight ranges

106–250

251–400

0.163

0.199

401–570

0.135

0.128

FCR

250–570

0.147

0.154

p value ≤ 0.05. 
ADG – average daily gain, DF – days of fattening, FCR – feed convertion ratio, BW – body weight

During the whole experiment bulls fed with concentrate containing corn DDGS were gaining about 115 g more per day (about 9.9%). Also FCR was higher in his group (0.007). This entailed with reducing by 22 days experimental fattening period (about 8%) in trial group.

Carcass characteristic results demonstrate a low but comparable dressing percentage in both analyzed groups (about 55%). There were slight differences between groups with respect to tissue percentage, but they were not significant (Table 3). Carcasses from the trial group of animals tended to contain less meat (1.24%) and more fat (0.48%) and bone (0.76%) than carcasses from control bulls. This indicates that extracted rapeseed meal replacing with corn DDGS in concentrate did not influence carcass characteristics.

Table 3. Carcass dissection results of steers slaughtered at approximate 570 kg body weight

Trait

control group

trial group

Kg

sd

%

Kg

sd

%

Meat in cuts

           

fore ribs

6.18

0.69

4.04

6.15

0.98

3.95

ribs

4.47

0.68

2.93

4.83

0.73

3.10

lion

4.84

0.48

3.17

5.24

0.75

3.37

round

29.47

1.27

19.29

28.89

2.28

18.58

shoulder

8.49

0.91

5.54

8.28

1.11

5.32

sirloin

2.03

0.07

0.13

2.06

0.15

1.32

Carcass composition

           

meat

116.46

3.99

76.25

116.59

3.29

75.01

fat

7.34

1.72

4.81

8.23

1.10

5.29

bone

28.94

4.57

18.94

30.64

1.60

19.7

Half carcass weight

152.74

5.45

155.46

9.71

Table 4. Steers' intramuscular fat fatty acid profile, %

Fatty acid

control group

trial group

sd

sd

C 10:0

0.073

0.012

0.067

0.012

C 12:0

0.078

0.015

0.068

0.012

C 14:0

2.69

0.358

2.650

0.258

C 14:1

0.537

0.095

0.625

0.116

C 15:0

0.344

0.080

0.361

0.035

C 16:0

22.045

1.392

21.960

0.553

C 16:1

2,665

0.306

2.832

0.406

C 17:0

1.037

0.245

0.975

0.172

C 17:1

0.634

0.177

0.640

0.065

C 18:0

18.437

1.923

16.839

1.263

C 18:1

36.510

1.436

36.829

1.442

C 18:2

3.419 a

0.540

4.511 b

0.771

C 18:3

0.371

0.056

0.363

0.030

C 20:0

0.015

0.023

0.134

0.011

C 20:2

0.146

0.026

0.160

0.020

C 20:3

0.058

0.012

0.060

0.010

C 20:4

0.133

0.037

0.017

0.085

Fatty acid sum
SFA
MUFA

       

43.678

41.945

-

39.712

40.286

PUFA

4.130

5.111

p value ≤ 0.05.
SFA – saturated fatty acids, MUFA – monounsaturated fatty acids, PUFA – polyunsaturated fatty acids

Statistically significant differences were found in linoleic acid (C 18:2) percentage between the trial and control group (Table 4). Intramuscular fat from animals fed with DDGS contained more of that fatty acid than from control animals, which is important considering potential consumer health. Percentage of other fatty acids did not differ between groups, though more unsaturated fatty acids was observed in trial animals.

DISCUSSION

Similarly as in the present study, Eun et al. [3] conducted fattening from 257 to 370 kg body weight in the first stage, and up to 590 kg in finishing period. They found that DDGS addition caused a significant increase in an average daily gain of about 0.11–0.18 kg, depending on a level of supplementation (10–17% of feed dry matter), comparing to the control group (p value=0.05). This corresponds with results of the present study. Also higher FCR was observed in all groups regardless to the percentage of addition. The authors suggest that the higher DDGS addition is, the lower dry matter intake is registered (p<0.01), which partially can explain higher FCR in animals fed with corn DDGS. Similar result was observed in experimental fattening of heifers with initial body weight of about 265 kg [9]. Animals fed with 0.56 kg addition of DDGS were gaining more intensively and had higher FCR than heifers fed with corn grain. Higher addition of dried distiller grain in feed (about 2.2kg) did not bring the expected effect. This observation was confirmed also by Depenbusch et al. [1], who defined an optimal level of DDGS supplementation at 15% of feed dry matter. These results are in accordance with our study, where corn DDGS was about 17% of all dry matter intake (concentrate and straw). During finishing FCR decreased in both groups, especially in trial animals, which could have been caused by reduced gain after an intensive growth period, and lowered DDGS level in the concentrate. Many researchers did not find a significant improvement of an average daily gains and FCR in finishing period (initial body weight about 350–370 kg) when animals were fed with dried distillers grain addition [2,3,19]. Ham et al. [6] however, found that effect of DDGS on gains and improvement of fodder intake, while fattening animals with initial body weight of about 392 kg. Also higher dry matter intake in trial group was observed in this study. Although differences between control and trial group were found in ADG and FCR in finishing period, author show that younger animals use DDGS supplementation more efficiently than older ones. Peter et al. [10], conducted experimental fattening of heifers with initial body weight about 239 kg for 84 days using corn dried distillers grain (DDG). The results show that trial animals differed from the control group ones and had higher ADG and FCR. Also using wet distillers grain with soluble (DDGS) resulted with similar effect and the difference was even greater than when  DDGS was used [6].

The results of the present study indicate that carcasses from animals fed with DDGS have slightly higher fat percentage than animals from the control group, but this difference was not significant. This corresponds with observations of Vander Pol et al. [19], who demonstrated that animals fed with an addition of DDGS had more of subcutaneous fat, but this difference was not significant. Also Depenbusch et al. [2] did not find any differences in this parameter between feeding with and without DDGS. Though  in other study Depenbusch et al. [1] conducted experimental feeding with DDGS and found significant linear relation between percentage of this component and subcutaneous fat. Increasing addition of dried distillers grain caused a decrease of fat amount. The cause of this phenomenon was probably the lower final body weight of heifers fed with DDGS supplementation. While increasing percentage of DDGS in feed, dry matter intake was decreasing, causing lower body weight at slaughter and less fattened carcass. Low dressing percentage of analyzed carcasses may be a result of the high share of Holstein – Friesian genes, though it was not effected by DDGS addition. Also Gunn et al. [5] did not find any differences in this parameter between animals fed with addition of dried distiller grain and control group.

The higher level of linoleic fatty acid (C18:2) in intramuscular fat observed in the present study, when bulls were fed with concentrate containing dried distillers grain with solubles  corresponds with results of other researchers. Gill et al. [4] found a relation between beef cattle feeding with DDGS and fatty acid profile. Irrespectively of plant used to its production (corn or sorghum), DDGS in feed increased level of C18:1 trans -11 fatty acid which is a precursor of certain forms of CLA. Moreover, highly significant increase was observed in the level of one of CLA forms (C18:2 trans-10, cis12) in trial animals fat comparing to those, which diet did not contain corn or sorghum DDGS. Also highly significant influence was found due to total amount of poly-unsaturated fatty acids and percentage of other forms of CLA in intramuscular fat. Similar results were observed in the research conducted by Depenbusch et al. [1], who shown, that the higher level of DDGS was given to animals, the higher level of CLA and PUFA was found in their fat. Also the experiment conducted on fattened pigs indicate that there is significant linear relation between increasing percentage of DDGS in feed and higher level of linoleic acid in subcutaneous and abdomen fat [16].

CONCLUSIONS

  1. The replacement of extracted rapeseed meal with corn DDGS in concentrate used for fattening of young bulls allows to obtain a higher average daily gain (about 9.9%), more effective feed use (about 5%) and a decrease of a total fattening period by 8%, and allows to achieve measurable financial benefits due to respectively similar cost of components used for the preparation of the concentrate.

  2. Intramuscular fat of bulls fed with concentrate containing DDGS had significantly higher level of linoleic fatty acid than the control group.

  3. No effect of corn DDGS supplementation on decreasing dressing or tissue percentage was found.

  4. Corn DDGS is a valuable feed component in fattening of young bulls.


REFERENCES

  1. Depenbusch B.E., Coleman C.M., Higgins J.J., Drouillard J.S., 2009. Effects of increasing levels of dried corn distiller's grains with solubles on growth performance, carcass characteristics, and meat quality of yearling heifers. J. Anim. Sci., 87, 2653–2663.

  2. Depenbusch B.E., Loe E.R., Quinn M.J., Corrigan M.E., Gibson M.L., Karges K.K., Drouillard J.S., 2008. Corn distillers grains with solubles derived from a traditional or partial fractionation process: Growth performance and carcass characteristics of finishing feedlot heifers. J. Anim. Sci., 86, 2338–2343.

  3. Eun J.-S., ZoBell D.R., Wiedmeier R.D., 2009. Influence of replacing barley grain with corn-based dried distillers grains with solubles on production and carcass characteristics of growing and finishing beef steers. Animal Feed Science and Technology, 152, 72–80.

  4. Gill R.K., VanOverbeke D.L., Depenbusch B., Drouillard J. S., DiCostanzo A., 2008. Impact of beef cattle diets containing corn or sorghum distillers grains on beef color, fatty acid profiles, and sensory attributes. J. Anim. Sci., 86, 923–935.

  5. Gunn P.J., Weaver A.D., Lemenager R.P., Gerrard D.E., Claeys M.C., Lake S.L., 2009. Effects of dietary fat and crude protein on feedlot performance, carcass characteristics, and meat quality in finishing steers fed differing levels of dried distillers grains with solubles. J. Anim. Sci., 87, 2882–2890.

  6. Ham G.A., Stock R.A., Klopfenstein T.J., Larson E.M., Shain D.H., Huffman R.P., 1994. Wet corn distillers byproducts compared with dried corn distillers grains with solubles as a source of protein and energy for ruminants. J. Anim. Sci., 72, 3246–3257.

  7. Kleinschmit D.H., Anderson J.L., Schingoethe D.J., Kalscheur K.F., Hippen A. R., 2007. Ruminal and intestinal degradability of distillers grains plus solubles varies by source. J. Dairy Sci., 90, 2909–2918.

  8. Kleinschmit D.H., Schingoethe D.J., Hippen A.R., Kalscheur K.F., 2007. Dried distillers grain plus solubles with corn silage or alfaalfa hay as the primary forage source in dairy cow diets. J. Dairy Sci., 90, 5587–5599.

  9. Loy T.W., Klopfenstein T.J., Erickson G.E., Macken C.N., MacDonald J.C., 2008. Effect of supplemental energy source and frequency on growing calf performance. J. Anim. Sci., 86, 3504–3510.

  10. Peter C.M., Faulkner D.B., Merchen N.R., Parrett D.F., Nash T.G., Dahlquist J.M., 2000. The effects of corn milling coproducts on growth performance and diet digestibility by beef cattle. J. Anim. Sci., 78, 1–6.

  11. Schingoethe D.J., 2006. Can we feed more distillers grains?. Tri-State dairy nutrition conference. April 25–26, 71–76.

  12. Schingoethe D.J., 2006. Feeding Ethanol Byproducts to Dairy and Beef Cattle. Proc. CA Anim. Nutr. Conf., May 10–11, Fresno, CA, 49–63.

  13. Schingoethe D. J., 2006. Utilization of DDGS by Cattle. Proc.27th Western Nutrition Conf, Winnipeg, Manitoba, Canada, September 19–20, 61–74.

  14. Świątkiewicz S., Koreleski J., 2007. Wywary zbożowe uzyskiwane w procesie produkcji etanolu paliwowego w żywieniu  drobiu [Distillers grains obtained in the ethanol fuel production in poultry nutrition]. Roczniki Naukowe Zootechniki, Monografie i Rozprawy, 36 [in Polish].

  15. Tjardes K., Wright C., 2002. Feeding Corn Distiller's Co-Products to Beef Cattle. Animal & Range Science, ExEx 2036.

  16. White H.M., Richert B.T., Radcliffe J.S., Schinckel A.P., Burgess J.R., Koser S.L., Donkin S.S., Latour M.A., 2009. Feeding conjugated linoleic acid partially recovers carcass quality in pigs fed dried corn distillers grains with solubles. J. Anim. Sci., 87, 157–166.

  17. Windhorst H.-W., 2007. Bio-energy production – a threat to the global egg industry?. World's Poultry Science Journal, 563, 365–378.

  18. www.kib.pl – Strona Krajowej Izby Biopaliw [The Polish National Chamber of Biofuels website] [in Polish].

  19. Vander Pol K.J., Luebbe M.K., Crawford G.I., Erickson G.E., Klopfenstein T.J., 2009. Performance and digestibility characteristics of finishing diets containing distillers grains, composites of corn processing coproducts, or supplemental corn oil. J. Anim. Sci., 87, 639–652.

Accepted for print: 9.02.2010


Tadeusz Szulc
Institute of Animal Breeding,
Wrocław University of Environmental and Life Sciences, Poland
Chełmońskiego 38C, 51-630 Wrocław, Poland
phone: 71 320 57 62
email: tadeusz.szulc@up.wroc.pl

Jarosław Szurko
Pol-Lean Sp. z o. o., Łosice, Poland
Łosice, 55–095 Mirków, Poland
phone: 71 315 43 17
email: j.szurko@pol-lean.pl

Stanisław Wajda
Department of Commodity Science and Animal Raw Material Proce, University of Warmia and Mazury in Olsztyn, Poland
Oczapowskiego 5, 10-719 Olsztyn–Kortowo, Poland
phone: 0 89 523 32 26
email: ewabur@uwm.edu.pl

Anna Zielak-Steciwko
Institute of Animal Breeding,
Wrocław University of Environmental and Life Sciences, Poland
Chełmońskiego 38D, 51-630 Wrocław, Poland
phone: 71 320 57 73
email: anna.zielak@up.wroc.pl

Irmina Newlacil
Institute of Animal Breeding,
Wrocław University of Environmental and Life Sciences, Poland
Chełmońskiego 38C, 51-630 Wrocław, Poland
phone: 71 320 57 67
email: irmina.newlacil@gmail.com

Monika Demkowicz
Institute of Animal Breeding,
Wrocław University of Environmental and Life Sciences, Poland
Chełmońskiego 38C, 51-630 Wrocław, Poland
phone: 71 320 57 67
email: demkowicz.monika@gmail.com

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