TABLE 1.

Transmission and shedding of E. coli O157:H7 in naturally infected dairy calves

Calf no.bResult(s) of fecal and water sample testing for E. coli O157:H7 on specific dates (mo/day/yr)a
1/6/981/8/981/12/981/14/981/15/981/16/981/17/981/18/981/19/981/20/981/21/981/22/981/23/981/26/981/27/981/28/981/29/981/30/982/2/982/3/982/4/982/6/982/9/982/11/982/13/98
167+c+wd+, w+w++w−+w−++w++, w+Pe
166w−w−w−w−−, w−w−P−
160w−wfw−+w−++w+−, w−wf−, w−w−P+g
159w−w−w−w−−, w−w−P−
158w−w−w−w−−, w+wf−, w−−, w−w−P−
157+w−+wfw−+w−+w−+w−−, w−++w−+++P+h
156++++w+w−+++, w−w−−, w−w−+P−
4704+++w−−, w−w−+w−w−++w−−, w++w−P−
  • a Fecal samples collected on 11 December 1997 and 18 December 1997 tested negative for E. coli O157:H7; +, positive; −, negative.

  • b Calves are listed in order of pen placement with calf 167 located in the first pen immediately to the right of the entrance and proceeding to the back of the room. Calf 158 was in the back of the second row of four pens on the left side of the room and calf 4704 was in the first pen to the left of the entrance.

  • c The pen holding calf 167 was across a walkway from that of calf 156.

  • d w, water sample (100 ml) test result.

  • e P, postmortem examination of intestinal tract. Samples were collected from the abomasum, cecum, cranial colon, caudal colon, duodenum, ileum, jejunum, omasum, reticulum, and rumen and tested for the presence of E. coli O157:H7.

  • f The water container and contents from calf 157 were exchanged with those of calf 160 (17 January 1998) and those of calf 160 were exchanged with those of calf 158 (20 January 2000).

  • g Abomasum tested positive.

  • h Reticulum, cranial colon, and caudal colon tested positive.