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Copyright of MESO is the property of Zadruzna Stampa D.D. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article presents information on a study which examines the usefulness of enzyme-linked immunosorbent assay (ELISA) in the analyzing b-agonists clenbuterol and salbutamol in animal plasma and serum. In this study, two doses of clenbuterol and salbutamol were administered on experimental guinea pigs for seven days.

Copyright of MESO is the property of Zadruzna Stampa D.D. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of the study was to compare residue depletion of ractopamine HCl as a β-adrenergic agonist that promotes muscle growth of animals, from internal tissues on days after its repeat administration to animals. The experiment was carried out in 38 albino guinea pigs. Treated animals ( n = 30) were orally administered ractopamine HCl in a dose of 3.5 mg/kg body mass per day for 7 consecutive days. On days 1, 10, 20 and 30 of drug discontinuation, animals were randomly sacrificed and the liver, kidney, lung, heart, muscle, spleen and fat samples were collected. In all matrices, ractopamine concentration was determined using validated enzyme-linked immunosorbent assay (ELISA) as a quantitative screening method. The highest ractopamine concentration was recorded on day 1 in the lungs (55.80 ± 15.62 μg/kg), followed by the kidney (21.85 ± 3.91 μg/kg), spleen (12.59 ± 1.95 μg/kg), fat (10.17 ± 5.02 μg/kg), heart (9.73 ± 0.22 μg/kg), liver (5.58 ± 2.09 μg/kg), and lowest in muscle (2.21 ± 1.02 μg/kg). Ractopamine residues were detected in the lungs in the period of 30 days after withdrawal in significantly higher concentrations in comparison to other investigated matrices, suggesting that depletion of ractopamine from the lungs occurs at a much slower rate than its depletion from other internal tissues. [ABSTRACT FROM AUTHOR]

Copyright of MESO is the property of Zadruzna Stampa D.D. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of MESO is the property of Zadruzna Stampa D.D. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of this study was to investigate the contamination of feed with mycotoxins. A total of 103 samples of feed for poultry, pig and calves was collected at different animal feed factories in the central, eastern and north region of Croatia. The quantitative determination of aflatoxin B1 (AFB1), ochratoxin A (OTA), zearalenone (ZEA), deoxynivalenol (DON), fumonisins B1, B2 and B3 (FUM) and T-2 toxin (T-2) concentration was done using the validated ELISA method. The observed results indicated an increased contamination of pig feed with Fusarium mycotoxins DON and ZEA with mean concentrations of 1454±1444 μg/kg and 153±161 μg/kg, higher than recommended in 20% and 5% of the samples, respectively. Higher DON concentrations than recommended were also observed in 7% of calves feed with a mean concentration of 1140±1288 μg/kg. The concentrations of AFB1, OTA and FUM in all the investigated samples in all country regions were according to the maximum allowed or recommended values in the European Union. [ABSTRACT FROM AUTHOR]

The paper reviews the literature data on the β-adrenergic agonists as a group of substances with anabolic effect in animals. The chemical structures of individual compounds are displayed as their basic properties, mechanism of action, physiological effects and adverse effects in humans and animals caused by exposure to anabolic doses of these substances. β- agonists in the body achieve the effect by binding to specific β-adrenergic receptors located on cell membranes of target tissues. Their use in anabolic dose in animals results in a significant increase in muscle mass and a decrease in body fat mass, better utilization of food, increased growth of animals and improved organoleptic properties of meat produced. In the last two decades, in some countries of the European Union, β-agonists were illegally used during the fattening of animals, with the aim to achieve significant yield in meat production and higher economic profit. A misuse of the clenbuterol as the most important representative has caused adverse effects on human and animal health. In the European Union, as well as in Croatia, the use of these substances with anabolic purposes in animals for meat production is prohibited, and the control of abuse is carried out through national residue monitoring. [ABSTRACT FROM AUTHOR]

Copyright of MESO is the property of Zadruzna Stampa D.D. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of MESO is the property of Zadruzna Stampa D.D. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of MESO is the property of Zadruzna Stampa D.D. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of MESO is the property of Zadruzna Stampa D.D. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of this study was to investigate the possibilities of ochratoxin A (OTA) reduction in home-made meat products. Meat sausages (n = 50) produced from raw materials coming from pigs exposed to OTA-contaminated feed, were subject to common heat processes practiced in households (cooking, frying and baking). Concentrations of OTA in pre- and post-processed products were quantified using a validated immunoassay method, enzyme-linked immunosorbent assay, and confirmed using a high-performance liquid chromatography with fluorescence detection. In line with the differences in recipes used and the degree of OTA accumulation in raw materials, OTA concentrations established in Mediterranean and roast sausages were lower than those found in liver and blood sausages. Baking of contaminated sausages at the temperatures of 190-220°C (for 60 min) resulted in significant reduction of OTA levels (75.8%), while 30-min cooking (at 100°C) and frying (at 170°C) proved to be significantly less effective (e.g. yielding OTA reductions of 7.4% and 12.6%, respectively). The results pointed out that despite high OTA stability, heat processes are capable of reducing its concentration in home-made meat products, depending on the processing modality used.

The aim of this study was to determine ochratoxin A (OTA) concentrations in the raw materials and cooked meat products made from pigs sub-chronically exposed to OTA. The treated animal group (n=5) was administered with 300 μg OTA/kg of feed for 30 days, whereas the control group (n=5) was left untreated. OTA concentrations were quantified using immunoassay (ELISA) and high performance liquid chromatography with fluorescence detection (HPLC-FD). OTA concentration was the highest in the kidney, followed by the lungs, liver, blood, spleen, heart, and adipose tissue. As for the final meat products, the highest average OTA concentration was detected in black pudding sausages (14.02±2.75 μg/kg), then in liver sausages (13.77±3.92 μg/kg), while the lowest was found in pâté (9.33±2.66 μg/kg). The results pointed out that a sub-chronic pig exposure leads to the accumulation of OTA in raw materials and consequently in meat products, whose level of contamination is directly dependent on OTA contents in raw materials used for their production., (© 2013.)

The presence of ochratoxin A (OTA) was determined in traditional dry-cured meat products made from sub-chronically OTA-exposed pigs. The experimental group of pigs (n = 5) was treated with 300 µg OTA kg(-1) of feed during 30 days, whereas the control group (n = 5) remained untreated. After the household production of six types of dry-cured meat products based on traditional recipes, OTA residues were determined in final products produced from each treated and untreated animal using an immunoenzymatic technique (ELISA) and HPLC with fluorescence detection (HPLC-FD). The analytical methods showed acceptable analytical performance results and high correlation coefficients. Mean OTA concentrations ranged from 4.51 ± 0.11 µg kg(-1) in smoked ham to 6.87 ± 2.01 µg kg(-1) in home-made Slavonian sausage. The study demonstrated that pig exposure to OTA leads to the accumulation of OTA residues in muscle and adipose tissue used for the production, and consequently results in contamination of the final meat products.

The aim of this study was to investigate the contamination of pig feed with moulds and the occurrence of mycotoxins. A total of 30 feed samples were collected at different animal feed factories in the north-western part of Croatia. Mycological analysis showed that the total number of moulds ranged from 1 × 10(3) to 1 × 10(5) cfu/g with samples contaminated with Aspergillus spp. (63 %), Penicillium spp. (80 %), and Fusarium spp. (77 %). A determination of aflatoxin B1 (AFB1), ochratoxin A (OTA), zearalenone (ZEA), deoxynivalenol (DON), T-2 toxin (T-2) and fumonisin (FUM) concentration was done using the validated ELISA method. The mean concentrations of AFB1 (0.5 ± 0.6 μg/kg), OTA (1.53 ± 0.42 μg/kg) and FUM (405 ± 298 μg/kg) were below the maximum levels or recommended values in the EU in all the investigated samples. The observed results indicated an increased contamination of pig feed with Fusarium mycotoxins DON and ZEA with mean concentrations of 817 ± 447 and 184 ± 214 μg/kg, higher than recommended in 40 and 17 % of the analysed samples, respectively.

Maize (Zea mays) considered to be one of the most frequent crops in Croatia, is often contaminated with Fusarium mycotoxins. The aim of this study was to investigate the possible contamination of maize with T-2 toxin and fumonisins on 46 samples from different regions of Croatia. The highest concentrations of T-2 toxin and fumonisins were 210 and 25,200 ng/g, with mean values of 110 and 4,509 ng/g, respectively, pointing to maize contamination with these mycotoxins after the period of the year with extremely high rainfall.

The objective of this study was to investigate the effect of ochratoxin A (OTA) on serum biochemical parameters of pigs during subchronic treatment with 300 μg OTA/kg of feed for 30 days. OTA treatment resulted in significantly higher (p < 0.05) serum levels of creatinine, urea, potassium and alkaline phosphatase, and significantly lower levels of glucose and total protein. These changes in serum biochemical parameters in treated pigs were indicative of impaired liver and kidney function caused by OTA exposure.

Ractopamine is a β(2)-adrenergic agonist, which reduces fat deposition and promotes muscle growth in animals for meat production. In the European Union countries, systematic monitoring and control of this contaminant residue is regularly performed by use of validated analytical methods of detection in different biological materials. The aim of the present study was to assess persistence of ractopamine in retina as a pigmented tissue by determination of its residues using UPLC-MS/MS as a quantitative confirmatory method after pig exposure to a ractopamine dose of 0.51 mg/kg b.w. Experimental group (n=9) of pigs were orally administered ractopamine for 28 days and then randomly sacrificed (n=3) on days 1, 3 and 8 of treatment discontinuation, whereas control animals (n=3) were left untreated. Study results showed mean ractopamine residue concentrations of 110.36 μg/kg, 67.11 μg/kg and 89.93 μg/kg on days 1, 3 and 8 after withdrawal, respectively, indicating high accumulation of ractopamine in retina despite a low dose applied. These data pointed to high affinity of ractopamine for binding to the pigmented segment of the eye, thus supporting the use of pigmented tissues as matrices in the regulatory monitoring of this β(2)-adrenergic agonist., (Copyright © 2012 Elsevier B.V. All rights reserved.)

The objective of this study was to measure residual ractopamine concentrations in tissues of pigs as experimental animals after treatment with dietary ractopamine for 28 consecutive days. Ractopamine was administered orally to the experimental group (n=9) in a dose of 0.1mg/kg body mass per day, whereas control animals (n=3) were left untreated. Treated pigs (60kg) were sacrificed on days 1, 3 and 8 of treatment discontinuation and residues were determined in kidney, liver, muscle, brain and heart tissues using previously validated enzyme-linked immunosorbent assay (ELISA) as a quantitative screening method. Validation showed good mean recoveries (approx. 70-90%) with acceptable inter- and intra-day relative standard deviations (RSD<13%), demonstrating the method efficiency in determination of ractopamine tissue concentrations. The highest ractopamine concentration on day 1 (24h) after the last exposure was recorded in the kidney (12.49±7.96ng/g), followed by the liver (7.21±2.73ng/g), heart (1.26±0.12ng/g) and brain (0.63±0.05ng/g); at this time of withdrawal, residues were not detected in the muscle. Ractopamine was depleted rapidly from all study tissues, with mostly no detectable residues on day 8 of withdrawal., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

The aim of this study was to determine feed and urinary levels of zearalenone. A total of 114 samples, 64 feeding stuffs (commodities, pig and cattle feed), and 50 urine samples were analyzed by the use of enzyme-linked immunosorbent assay (ELISA). Zearalenone was detected in 68.7% of feeding stuffs, while all urine samples except for four yearling samples were positive for zearalenone. The maximum zearalenone concentration in feeding stuffs and urine was 577 ng/g and 241.1 ng/mL, respectively. Although zearalenone concentrations in some samples were high, the risk for humans was negligible since the calculated concentrations in meat were below the tolerable daily intake (TDI).

Maize (Zea mays) is one of the most common crops in Croatia that is often contaminated with mycotoxins. The enzyme linked immunosorbent assay (ELISA) method as a screening immunological method has become very popular in the determination of mycotoxins contamination of cereals, as it has many advantages such as a rapid and simple determination of their concentration. In this present study, 40 maize samples collected from animal feed factories were analyzed for the concentration of deoxynivalenol (DON) and fumonisin (FUM) using the validated ELISA method of two different kit manufacturers to investigate the correlation of the determined mycotoxins concentration. The correlation coefficients for the concentration of DON and FUM, obtained using different kit manufacturers, were r = 0.9698 and r = 0.9303, respectively, yielding a high correlation between the applied ELISA methods. Concerning the legislation, in one maize sample, the DON concentration higher than the maximum recommended value was determined (16.24 mg/kg), whereas the FUM concentration in all the analyzed samples, without exception, were in accordance with recommended values.

Hair has been shown to be an excellent site for the accumulation of different drugs including β-agonists, and therefore, it would be an appropriate matrix for surveillance for the presence of drug residues. The aim of this study was to determine concentrations and to compare accumulation of two different β-agonists in black and white mice hair by use of ELISA as a screening quantitative method. The study included 200 8-week-old white and black mice. One group of black mice and one group of white mice were treated with clenbuterol in a dose of 2.5 mg/kg body mass per os for 28 days. Other animals were treated in the same way with salbutamol. The highest (±SD) clenbuterol concentration of 631.4 ± 23.5 ng/g in black hair and 228.5 ± 156.2 ng/g in white hair was determined on day 1 of treatment withdrawal. Study results revealed the black-to-white hair ratio of clenbuterol accumulation to be 1:2-1:4 and of salbutamol accumulation 1:1.4. The mean (±SD) salbutamol concentrations determined on day 1 of treatment withdrawal was 23.9 ± 0.9 ng/g and 16.4 ± 1.1 ng/g in black and white hair samples, respectively. The study demonstrated that residues could be determined in hair samples even after a 30-day withdrawal period.

Data on the occurrence of T-2 and HT-2 toxins in commodities and feed in Croatia and in Europe are very limited. In the present study, 50 feed and commodity samples tested for the presence of these mycotoxins yielded highest concentrations in cattle feed (67.68 ng/g) and oat samples (32.94 ng/g). In the future, screening should include greater numbers of feed and commodity samples to shed more light on the presence of T-2 and HT-2 toxins.

The aim of the present study was to assess the persistence of clenbuterol residues in retinal tissue of pigs after repeated administration in a growth-promoting dose, using enzyme-linked immunosorbent assay (ELISA) as a screening method for quantitative determination. A growth-promoting dose of clenbuterol (20 μg/kg body mass per day) was administered orally to the experimental group (n = 6) for 21 days, whereas control animals (n = 3) were left untreated. Clenbuterol-treated pigs were randomly sacrificed (n = 3) on days 0 and 45 of treatment discontinuation, and clenbuterol residues were determined in retinal tissue dissected from the eye. ELISA was found to be acceptable for quantitative determination of clenbuterol in retinal samples because previous method validation yielded mean recovery values of 84.3-96.5% with variation coefficients < 14%. The mean (± SD) retinal clenbuterol concentration was 1874 ± 114 ng/g immediately upon clenbuterol withdrawal (day 0) and 73 ± 4 ng/g on the last day post-withdrawal (day 45). Study results pointed to a very high potential of clenbuterol accumulation in retinal tissue and marked persistence of clenbuterol residues upon anabolic dose administration, suggesting retinal tissue to be a very useful matrix for effective control of residual clenbuterol in food-producing pigs.