Characterization of Shiga toxin-producing Escherichia coli (STEC) in feces of healthy and diarrheic calves in Urmia region, Iran
Background and Objectives: Shiga toxin-producing Escherichia coli (STEC) have emerged as human pathogens and contamination of foods of animal origin has been a major public health concern. The aim of the present study was to determine the dissemination of STEC in healthy and diarrheic calves in Urmi...
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| Format: | Article |
| Language: | English |
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Tehran University of Medical Sciences
2012-06-01
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| Series: | Iranian Journal of Microbiology |
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| Online Access: | https://ijm.tums.ac.ir/index.php/ijm/article/view/710 |
| _version_ | 1818407902708236288 |
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| author | Saei H Dastmalchi N Ayremlou |
| author_facet | Saei H Dastmalchi N Ayremlou |
| author_sort | Saei H Dastmalchi |
| collection | DOAJ |
| description | Background and Objectives: Shiga toxin-producing Escherichia coli (STEC) have emerged as human pathogens and contamination of foods of animal origin has been a major public health concern. The aim of the present study was to determine the dissemination of STEC in healthy and diarrheic calves in Urmia region which is located in West Azerbaijan province, Iran.
Materials and Methods: In the current study, a total of 124 Escherichia coli isolates from clinically healthy (n = 73) and diarrheic calves (51) belonging to 6 different farms located in West Azerbaijan province, Iran, were screened by the polymerase chain reaction (PCR) assay for the presence of virulence genes characteristic for STEC, that is, Shiga-toxin producing gene(s) (stx1, stx2), intimin (eaeA) and enterohemolysin (hlyA).
Results: STEC isolates were recovered from 21.92% (16/73) in healthy calves, and 19.6% (10/51) in diarrheic calves. Overall, PCR results showed that 6 (23.1%) isolates carried stx1 gene, 7 (26.92%) possessed stx2 gene while 13 isolates (50%) gave positive amplicon both for stx1 and stx2 genes. All stx positive isolates were assayed further to detect eaeA and hlyA sequences. Seven out of the 26 (26.92%) Shiga toxin gene positive isolates were positive for the eaeA gene, and 15 (57.69%) were positive for the hlyA gene. Both virulence genes (eaeA and hlyA) in the same isolate were observed in 5 (19.23%) of the stx+ isolates. In total, diverse virulence gene profiles were detected, from which isolates with the genetic profile stx1 stx2 hlyA was the most prevalent. In addition, eaeA gene was more evident in isolates from diarrheic calves than in healthy calves.
Conclusion: There was no significant difference in detecting STEC isolates between healthy and diarrheic calves. It seems that calves to be the reservoir of STEC within the herds and calf management may represent specific control points for reducing STEC spread within dairy units. |
| first_indexed | 2024-12-14T09:35:13Z |
| format | Article |
| id | doaj.art-75fd02dfc7c64417b833c6e676a547ba |
| institution | Directory Open Access Journal |
| issn | 2008-3289 2008-4447 |
| language | English |
| last_indexed | 2024-12-14T09:35:13Z |
| publishDate | 2012-06-01 |
| publisher | Tehran University of Medical Sciences |
| record_format | Article |
| series | Iranian Journal of Microbiology |
| spelling | doaj.art-75fd02dfc7c64417b833c6e676a547ba2022-12-21T23:07:58ZengTehran University of Medical SciencesIranian Journal of Microbiology2008-32892008-44472012-06-0142Characterization of Shiga toxin-producing Escherichia coli (STEC) in feces of healthy and diarrheic calves in Urmia region, IranSaei H Dastmalchi0N Ayremlou1Department of Microbiology, Faculty of Veterinary Medicine and Department of Cellular and Molecular Biotechnology, Institute of Biotechnology, Urmia University, P.O. Box 1177, Urmia, Iran.Graduated from Faculty of Veterinary Medicine, Urmia University, P.O. Box 1177, Urmia, Iran.Background and Objectives: Shiga toxin-producing Escherichia coli (STEC) have emerged as human pathogens and contamination of foods of animal origin has been a major public health concern. The aim of the present study was to determine the dissemination of STEC in healthy and diarrheic calves in Urmia region which is located in West Azerbaijan province, Iran. Materials and Methods: In the current study, a total of 124 Escherichia coli isolates from clinically healthy (n = 73) and diarrheic calves (51) belonging to 6 different farms located in West Azerbaijan province, Iran, were screened by the polymerase chain reaction (PCR) assay for the presence of virulence genes characteristic for STEC, that is, Shiga-toxin producing gene(s) (stx1, stx2), intimin (eaeA) and enterohemolysin (hlyA). Results: STEC isolates were recovered from 21.92% (16/73) in healthy calves, and 19.6% (10/51) in diarrheic calves. Overall, PCR results showed that 6 (23.1%) isolates carried stx1 gene, 7 (26.92%) possessed stx2 gene while 13 isolates (50%) gave positive amplicon both for stx1 and stx2 genes. All stx positive isolates were assayed further to detect eaeA and hlyA sequences. Seven out of the 26 (26.92%) Shiga toxin gene positive isolates were positive for the eaeA gene, and 15 (57.69%) were positive for the hlyA gene. Both virulence genes (eaeA and hlyA) in the same isolate were observed in 5 (19.23%) of the stx+ isolates. In total, diverse virulence gene profiles were detected, from which isolates with the genetic profile stx1 stx2 hlyA was the most prevalent. In addition, eaeA gene was more evident in isolates from diarrheic calves than in healthy calves. Conclusion: There was no significant difference in detecting STEC isolates between healthy and diarrheic calves. It seems that calves to be the reservoir of STEC within the herds and calf management may represent specific control points for reducing STEC spread within dairy units.https://ijm.tums.ac.ir/index.php/ijm/article/view/710E. coliIranShiga toxincalves |
| spellingShingle | Saei H Dastmalchi N Ayremlou Characterization of Shiga toxin-producing Escherichia coli (STEC) in feces of healthy and diarrheic calves in Urmia region, Iran Iranian Journal of Microbiology E. coli Iran Shiga toxin calves |
| title | Characterization of Shiga toxin-producing Escherichia coli (STEC) in feces of healthy and diarrheic calves in Urmia region, Iran |
| title_full | Characterization of Shiga toxin-producing Escherichia coli (STEC) in feces of healthy and diarrheic calves in Urmia region, Iran |
| title_fullStr | Characterization of Shiga toxin-producing Escherichia coli (STEC) in feces of healthy and diarrheic calves in Urmia region, Iran |
| title_full_unstemmed | Characterization of Shiga toxin-producing Escherichia coli (STEC) in feces of healthy and diarrheic calves in Urmia region, Iran |
| title_short | Characterization of Shiga toxin-producing Escherichia coli (STEC) in feces of healthy and diarrheic calves in Urmia region, Iran |
| title_sort | characterization of shiga toxin producing escherichia coli stec in feces of healthy and diarrheic calves in urmia region iran |
| topic | E. coli Iran Shiga toxin calves |
| url | https://ijm.tums.ac.ir/index.php/ijm/article/view/710 |
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