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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

Tomasz Grenda, Elżbieta Kukier, Magdalena Goldsztejn and Krzysztof Kwiatek

Abstract

A PCR-based procedure for detection of C. botulinum C and D in corn silage samples was validated. During the validation, method specificity, sensitivity, and accuracy were determined according to PN - EN ISO 16140:2004. Additionally, the specificity of the validated methods was proved by sequence analysis of PCR products obtained from examination of samples connected with botulism cases in cattle and mallard ducks. Limit of detection was estimated according to the Spearman - Kärber formula and expressed as LOD50. The obtained results showed that a 100% specificity was achieved. The sequencing of PCR products revealed 99% identity with sequences of bont/C and bont/D genes deposited in the GenBank. The sensitivity value ranged from 63.3% for C. botulinum type C to 75% for type D. The accuracy value varied from 72% for type C to 81.3% for type D. LOD50 was estimated at the levels of 0.272 (0. D 188-0395) spore/g for type C and 0.17 (0.1-0.289) spore/g for type D. The described PCR-based procedure enabled detection of C. botulinum C and D at the stage of liquid culture. This makes examination of feed samples possible without isolation process. The presented procedure could support the diagnosis of botulism by faster and specific laboratory examination process.

Open access

Tomasz Grenda, Magdalena Grabczak, Krzysztof Kwiatek and Andrzej Bober

Abstract

Introduction: The aim of this study was to evaluate the prevalence of Clostridium botulinum and Clostridium perfringens in food samples purchased from Polish producers. Material and Methods: The analyses were performed on 260 food samples collected in Lublin and Subcarpathian regions: 56 of smoked meat, 21 of pork meat, 20 of dairy products, 26 of vegetable and fruit preserves, 40 of ready-to-eat meals, 27 of fish preserves, and 70 of honey collected directly from apiaries. Results: C. botulinum strains were isolated from 2.3% (6/260) of samples and the isolates were classified as toxin types A (4/260) and B (2/260). C. perfringens strains were isolated from 14% (37/260) of samples. All the isolates were classified as toxin type A, 28 of them were able also to produce α toxin and 9 - β2 toxin. Conclusion: On the basis of the obtained results it could be suggested that risk assessment, especially regarding the entire honey harvesting process, should be provided in order to ensure the microbiological safety of the products to be consumed by infants and people with a weakened immune system.

Open access

Elżbieta Kukier, Magdalena Goldsztejn, Tomasz Grenda, Krzysztof Kwiatek, Dariusz Wasyl and Andrzej Hoszowski

Abstract

The aim of the study was the assessment of microbiological quality of compound feed used in Poland in 2007-2010. The examinations were done at all veterinary diagnostic laboratories operating in the frame of official laboratory system. The occurrence of Salmonella sp. and counts of Enterobacteriaceae family, mesophilic aerobic bacteria, total microorganisms, and fungi were assessed. Assays were done following Polish, European, and international standards. Percentage of contamination of compound feed for poultry, pigs, and cattle by Salmonella sp. ranged from 0% to 3.5%. The highest contamination level by Enterobacteriaceae bacteria were detected in wet petfood. No more than 106 cfu/g of aerobic bacteria and no more than 105 cfu/g of fungi were detected in the feed. The results of the study revealed that the microbiological quality of compound feed used in Poland in 2007-2010 was better than the quality of the feed used in 2003-2006.

Open access

Elżbieta Kukier, Magdalena Goldsztejn, Tomasz Grenda and Krzysztof Kwiatek

Abstract

Clostridium perfringens isolates were obtained from pigs of five porcine farms in Poland. The presence of C. perfringens was detected in 92% of faeces samples and its number ranged from 1.0 x 101 cfu/g to 1.2 x 107 cfu/g. All the isolates belonged to type A and 48.7% of them contained cpb2 gene. The qualitative assessment of toxin genes expression by type A subtype β2 isolates showed expression of cpa gene in 100% of strains and cpb2 gene in 71% of the analysed strains. The isolate from one-day-old piglets demonstrated also the expression of cpa and cpb2 genes.

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

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.

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.