Year-round Monitoring of Verotoxin-producing Escherichia coli from Feces of Dairy Cattle

  • Kobayashi, Y. (Graduate School of Agriculture, Hokkaido University) ;
  • El-Sawy, H.B.I. (Graduate School of Agriculture, Hokkaido University)
  • Received : 2006.05.17
  • Accepted : 2006.11.02
  • Published : 2007.05.01


A PCR-aided monitoring of verotoxin-producing Escherichia coli (VTEC) was performed over the period of 12 months by using fresh feces collected monthly from 5 dairy cows that had been identified as VTEC carriers. The PCR products were confirmed to be verotoxin genes by Southern hybridization using a gene fragment of verotoxin 2 as a probe. Although seasonal variation of VTEC shedding seemed to depend on each cow, several factors may have influenced the frequency of detection. Shedding of VTEC tended to be reduced during grazing from the middle of May up to the beginning of October. Only one cow was positive for VTEC in August. Dry-off was also suggested to have a depressive effect on VTEC shedding, i.e. 3 of 4 dry cows showed no shedding of VTEC. Contrary to these factors, winter or indoor rearing tended to increase VTEC with only 5/24 samples being negative during the period from November to April. Total VFA concentration was higher (p<0.05) in VTEC-positive feces than in VTEC-negative feces, while fecal pH and VFA proportions were not different. Partial sequences of verotoxin genes from feces of 4 VTEC-positive cows were nearly identical (99-100%), suggesting that gut bacteria sharing the same gene were distributed among the cows. The present results indicate that grazing and dry-off could be factors which reduce VTEC shedding, while winter/indoor rearing may be a factor which increases the shedding, possibly through on-farm interactions.


Dairy Cattle;Feces;Verotoxin Genes;Escherichia coli;PCR Detection;Diet Change


  1. Davis, M. A., K. A. Cloud-Hansen, J. Carpenter and C. J. Hovde. 2005. Escherichia coli O157:H7 in environments of culturepositive cattle. 2005. Appl. Environ. Microbiol. 71:6816-22.
  2. Harmon, B. G., C. A. Brown, S. Tkalcic, P. O. E.Mueller, A. Parks, A. V. Jain, T. Zhao and M. P. Doyle. 1999. Fecal shedding and rumen growth of Escherichia coli O157:H7 in fasted calves. J. Food Protect. 62:574-579.
  3. Hovde, C. J., P. R. Austin, K. A. Cloud, C. J. Williams and C. W. Hunt. 1999. Effect of cattle diet on Escherichia coli O157:H7 acid resistance. Appl. Environ. Microbiol. 65:3233-3235.
  4. Miyao, Y., Y. Somura, T. Suzuki, A. Kai, T. Itoh, K. Hirayama and K.Itoh. 1996. Isolation of verocytotoxin-producing Escherichia coli from rectum and cecum of healthy cattle. J. Jap. Vet. Med. Assoc. 49:46-51.
  5. Thran, B. H., H. S. Hussein, M. R. Hall and S. F. Khaiboullina. 2001. Occurrence of verotoxin-producing Escherichia coli in dairy heifers grazing an irrigated pasture. Toxicol. 159:159-169.
  6. Gilgen, M., P. Hubner, C. Hofelein, J. Luthy and U. Candrian. 1998. PCR-based detection of verotoxin-producing Escherichia coli (VTEC) in ground beef. Res. Microbiol. 149:145-154.
  7. Jonsson, M. E., A. Aspan, E. Eriksson and I. Vagsholm. 2001. Persistence of verocytotoxin-producing Escherichia coli O157:H7 in calves kept on pasture and in calves kept indoors during the summer months in a Swedish dairy herd. International J. Food Microbiol. 66:55-61.
  8. Kobayashi, Y., M. Sato, H. Taguchi, S. Koike, H. Nakatsuji and K. Tanaka. 2004. Molecular detection of verotoxigenic Escherichia coli (VTEC) from animal feces for screening VTEC-shedders. Asian-Aust. J. Anim. Sci. 17:423-427.
  9. Johnson, R. P., J. B. Wilson, P. Michel, K. Rahn, S. A. Renwick, C. L. Gyles and J. S. Spika. 1999. Human infection with verocytotoxigenic Escherichia coli associated with exposure to farms and rural environments. In: Escherichia coli O157 in farm animals. (Ed. C. S. Stewart and H. J. Flint). CABI Publishing, Willingford, UK. pp. 147-168
  10. Schmidt, H., M. Montag, J. Brockemuhl, J. Heeseman and H. Karch. 1993. Shiga like toxin II related cytotoxins in Citrobacter freundii strains from humans and beef samples. Infect. Immunity 61:534-543.
  11. Diez-Gonzalez, F., T. R.Callaway, M. G. Kizoulis and J. B. Russell. 1998. Grain feeding and the dissemination of acid-resistant Escherichia coli from cattle. Sci. 281:1666-1668.
  12. Sambrook, J. and D. W. Russell. 2001. Molecular cloning: a laboratory manual, 3rd Ed. Cold Springs Harbor, New York.
  13. Rasmussen, M. A., W. C. Cray Jr., T. A. Casey and S. C. Whipp. 1993. Rumen contents as a reservoir of enterohemorrhagic Escherichia coli. FEMS Mirobiol. Let. 114:79-84.
  14. Grauke, L. J., I. T. Kudva, J. W. Yoon, C. W. Hunt, C. J. Williams and C. J. Hovde. 2002. Gastrointestinal tract location of Escherichia coli O157:H7 in ruminants. Appl. Environ. Microbiol. 68:2269-77.
  15. Rasmussen, M. A., T. L. Wickman, W. C. Cray Jr. and T. A. Casey 1999. Escherichia coli O157:H7 and the rumen environment. In: Escherichia coli O157 in farm animals. (Ed. C. S. Stewart and H. J. Flint). CABI Publishing, Willingford, UK. pp. 39-49.
  16. Purdy, K. J., T. M. Embley, S. Takii and D. B. Nedwell. 1996. Rapid extraction of DNA and rRNA from sediments by a novel hydroxyapatite spin-column method. Appl. Environ. Microbiol. 62:3905-3907.
  17. Sanz, M. E., M. R.Vinas and A. E. Parma. 1998. Prevalence of bovine verotoxin-producing Escherichia coli in Argentina. Eur. J. Epidemiol. 14:399-403.