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Open access

Tomasz Grenda, Elżbieta Kukier, Magdalena Goldsztejn, Krzysztof Kwiatek and Nina Kozieł

Abstract

As the test material mink feed with natural microflora was used. The analyses were conducted using Wrzosek and TPGY broth media, and Willis–Hobbs and Zeissler differential agar media. Wrzosek, Willis–Hobbs, and Zeissler media are described in Polish Standards approved by the National Standards Body in Poland and routinely used in detection of anaerobic bacteria in Poland. Detection and identification of C. botulinum was performed with a previously validated real-time PCR method based on ntnh gene detection, which is common in all C. botulinum toxotypes. The use of Wrzosek broth and Zeissler agar in routine analyses for detection and identification of C. botulinum was ineffective and limited. The obtained results showed the highest culturing process effectiveness in TPGY broth with 72 h incubation at 30°C and isolation on Willis–Hobbs agar. The real-time PCR method based on ntnh gene detection used in this study could be utilised as a supplementary tool to the mouse lethality assay.

Open access

Ewelina Patyra, Ewelina Kowalczyk and Krzysztof Kwiatek

Abstract

High performance liquid chromatography method with diode array detection (HPLC-DAD) was developed and optimised for the determination of tetracyclines (TCs) in medicated feedingstuffs. The extraction of the analyte from feedingstuffs was performed with Na2EDTA-McIlvaine buffer (pH 2.5 and pH 4). The extracts were cleaned up by solid phase extraction using octadecyl cartridges (C18). The samples were dried up and redissolved in the mixture of oxalic acid and methanol. Separation was performed on reserved phase column (Phenomenex C18, 250 x 4.6 mm, 5 μm) by multistep gradient elution, which provided better chromatographic separation. The analysis was performed at a wavelength of 390 nm. Validation study of the method revealed that all obtained calibration curves showed good linearity R= 0.9985 for doxycycline (DC) and R= 0.9981 for chlorotetracycline (CTC) over the range of 25-2,000 mg/kg. The analytical procedure was successfully adapted for quantitative determination of DC and CTC in medicated feedingstuff samples. Validation included determination of specificity, linearity, and repeatability. Mean recovery for spiked samples was 93.1% for CTC and 93.2% for DC. The results of validation of the analytical procedure proved that presented method is efficient, precise and useful for quantification of DC and CTC in medicated feedingstuffs.

Open access

Ewelina Patyra, Ewelina Kowalczyk and Krzysztof Kwiatek

Abstract

A chromatographic procedure for determination of oxytetracycline (OXT), tetracycline (TC), chlorotetracycline (CTC), and doxycycline (DC) in water samples was developed and was applied for the analysis of water samples collected from poultry and pig farms and environmental water samples. Samples were acidified with trifluoroacetetic acid to pH 3 and further purified by solid phase extraction using Oasis HLB cartridges. The samples were dried up and redissolved in the mixture of oxalic acid and methanol. Separation was performed on reserved phase column (Phenomenex column C18 , 250 mm × 4.6 mm, 5 μm) by multistep gradient elution, and detection was carried out at 360 nm for OTC and TC, 370 nm for CTC, and 350 nm for DC. The tetracyclines were eluted with the mobile phase of 0.05 M oxalic acid (pH 2.5), acetonitrile, and methanol. This method provided average recoveries of 83.53% to 108.59%, with coefficient of variations (CVs) of 2.41% to 8.64% in the range of 10 to 1000 μg/L OTC, TC, CTC, and DC in water. The linearity for the tetracyclines was determined by HPLC-DAD in the range 10 to 1000 μg/L, with the correlation coefficient (R) > 0.99. The LOD and LOQ for the tetracyclines in water samples ranged from 1.51 to 4.00 and 2.51 to 5.93 μg/L, respectively.

Open access

Anna Weiner, Ilona Paprocka, Agata Gołębiowska and Krzysztof Kwiatek

Abstract

The aim of the study was to gather and analyse available data concerning the presence of terrestrial animal constituents in feeds in Poland. A microscopic method of identification of the contaminants was used. Between 2012 and 2013, overall 16 139 samples of feeds were analysed, from which 282 (1.75%) contained elements from terrestrial animals. The percentage of feeds contaminated with such elements was lower in 2013. In 2012, among 8 499 samples analysed, 203 (2.39%) contained ingredients of animal origin, and in 2013, the elements were found in 79 (1.03%) out of 7640 samples. The percentage of feed samples positive for processed animal protein was relatively low and steadily decreasing. Furthermore, the microscopic method demonstrated to be a very sensitive technique for the detection of constituents of animal origin.

Open access

Elżbieta Kukier, Magdalena Goldsztejn, Tomasz Grenda, Krzysztof Kwiatek and Łukasz Bocian

Abstract

The study was conducted at all regional veterinary diagnostic laboratories. Feed materials were examined for Salmonella prevalence and contamination by Enterobacteriaceae, aerobic mesophilic bacteria, total plate count, fungi, Clostridium sp., and Bacillus cereus. Assays were done following international and Polish standards used in food and feed microbiology. Salmonella sp. were most often detected in oil seeds. In most of the examined feed ingredients, the number of Enterobacteriaceae did not exceed 10 cfu/g. The contamination by aerobic bacteria ranged most often from 101to 107 cfu/g, and the highest mycological contamination was noted in cereal grains (108 cfu/g). The results showed that microbial contamination of feed materials in regard to Enterobacteriaceae, fungi, and total plate counts declined over the past years.

Open access

Raikhan Mustafina, Balgabay Maikanov, Jan Wiśniewski, Michał Tracz, Krzysztof Anusz, Tomasz Grenda, Elżbieta Kukier, Magdalena Goldsztejn and Krzysztof Kwiatek

Abstract

The paper presents the first results of a study on the contamination of honey produced in the Republic of Kazakhstan with C. botulinum spores known to pose a potential infection threat to infants. During microbiological analysis, culturing methods with TPGY, Willis-Hobbs agar, FAA agar connected with PCR, sequencing, and a mouse bioassay were used. The C. botulinum contamination rate of honey was relatively low as determined, at 0.91%. Nonetheless, the potential danger of the bacteria to childrens’ health should not be neglected

Open access

Monika Przeniosło-Siwczyńska, Ewelina Patyra, Maja Chyłek-Purchała, Beata Kozak and Krzysztof Kwiatek

Abstract

The paper describes a microbiological method for the detection of antibacterial substances in feedingstuffs. The method allowed detection of the main antibiotic groups, including tetracyclines. In 2013-2014, a total of 171 feed samples were analysed to determine antibacterial substances. Among the analysed samples 84 (49.1%) were suspected to contain tetracyclines. Out of the 84 feeds analysed using chromatography, 28 (33.3%) contained undeclared tetracyclines, which were identified at concentrations ranging from 0.32 mg kg-1 to 48.98 mg kg-1.

Open access

Tomasz Grenda, Magdalena Grabczak, Magdalena Goldsztejn, Nina Kozieł, Krzysztof Kwiatek, Krystyna Pohorecka, Marta Skubida and Andrzej Bober

Abstract

Introduction: The aim of this study was examination of honey samples collected from apiaries situated in all Polish provinces for occurrence of Clostridium spp., especially C. perfringens.

Material and Methods: The study was carried out on 240 honey samples (15 samples/province). Estimation of Clostridium titre, its cultures and C. perfringens isolate characterisation were performed according to the standard PN-R-64791:1994. A multiplex PCR method for detection of genes coding cpa (α toxin), cpb (β), cpb2 (β2), etx (ε), iap (ι), and cpe (enterotoxin) toxins was used.

Results: Clostridium spp. was noticed in 56% (136/240) of samples, and its titres ranged between 0.1 g and 0.001 g. Clostridium perfringens occurrence was evidenced in 27.5% (66/240) of samples. All isolates were classified to toxinotype A.

Conclusions: Evidence of a high number of positive samples with occurrence of Clostridium spp. indicates a potential risk to consumers’ health. The infective number of Clostridium spp. is unknown; however, the obtained results have shown that a risk assessment on the entire honey harvesting process should be made in order to ensure microbiological safety. Moreover, a detailed study should be undertaken on the antibiotic resistance of C. perfringens isolates from honey samples.

Open access

Dariusz Bednarek, Katarzyna Dudek, Krzysztof Kwiatek, Małgorzata Świątkiewicz, Sylwester Świątkiewicz and Juliusz Strzetelski

Abstract

The aim of the study was to evaluate the immune effects of genetically modified (GM), insect resistant corn (MON810) expressing toxin protein of Bacillus thuringiensis, and glyphosate-tolerant soybean meal (Roundup Ready MON-40-30-2), which are used as the feed mixture components in domestic animals. The study was conducted on 60 pigs (36 fatteners and 24 sows), 20 calves, 40 broilers, and 40 laying hens. Each species was divided into four basic nutritional groups: group I (control) - conventional feed, group II - feed consisted of GM soybean meal and non-modified corn, group III - non-modified soybean meal and GM corn, group IV - GM soybean meal and GM corn. Moreover, in the experiment on fatteners two additional groups were formed: group V - animals fed both conventional soybean meal and bruised grain, and group VI - GM soybean meal and conventional bruised grain. The results of study did not reveal any significant effect of feed mixtures containing GM components on the immune response in all animals regardless of their species and technological producing groups.

Open access

Beata Szymczyk, Witold Szczurek, Sylwester Świątkiewicz, Krzysztof Kwiatek, Zbigniew Sieradzki, Małgorzata Mazur, Dariusz Bednarek and Michał Reichert

Abstract

Introduction: The influence of feeding genetically modified MON 810 hybrid maize on the growth and haematological and biochemical indices of rats was tested.

Material and Methods: Two conventional (non-GM) and two test (MON 810) lines of maize were used in semi-purified diets at the level of 40% w/w. The non-GM I, MON 810 I, non-GM II, and MON 810 II maize lines were near-isogenic. A total of 40 male 6-week-old Wistar-derived rats were assigned to four equal feeding groups corresponding to the four maize lines for 16 weeks. Overall, health, body weight gain, clinical pathology parameters, gross changes, and appearance of tissues were compared between groups.

Results: There were no statistically significant differences in the weight gain or relative organ weights of rats, but there were some non diet-related histopathological changes in the liver, kidneys, and spleen. Except for creatinine level, no diet-related effects were observed in haematology or most of the biochemical indices. Transgenic DNA of MON 810 maize was not detected in the tissues or faeces nor in the DNA of E. coli isolated from the rectum digesta of rats given transgenic feeds. In our experiment, various metabolic indices of rats fed non-GM diets or genetically modified (MON 810) maize for 16 weeks were similar. No adverse nutrition-related health effects were detected.

Conclusion: MON 810 maize seems to be as safe as the conventional maize lines.