Hair and fecal samples from 240 cattle at four slaughter plants were collected immediately post-stunning. Fecal samples were positive for E. coli O157:H7 at a rate of 5.8% while hide samples were culture positive for E. coli O157:H7 at a rate of 1.7%. Fecal samples were also collected from holding pens from one of the slaughter plants and 15 out of 919 samples were positive (1.6%) for E. coli O157:H7. No E. coli O157:H7 was found at one of the slaughter plants and no cattle were positive for both hair and fecal samples.
This suggests that fecal testing of pre-slaughter cattle is not dependable for determining which cattle carry the greatest potential for contaminating carcasses with E. coli O157:H7. Although hide incidence is at a lower rate, it has been shown to be a more common source of bacterial contamination. By providing a cleaner holding environment for cattle, it might be possible to minimize hair contamination regardless of fecal status for E. coli O157:H7.