Shedding of E. coli O157:H7 (FRIK 1275) in dairy calves following waterborne inoculation on three consecutive days

Calf no.bResult(s) of fecal and water sample testing for E. coli O157:H7 on specific dates (mo/day/yr)a
170−, wc−, w−w−+d+Pe
169−, w−−, w−w−P−
168−, w−w−P−
165−, w−−, w+dw−+d++P−
171−, If+, w+, I+d, w+, I+, w−+w−++++P+g
163−, If+, w−, I+, w+, I−, w−+w−++++P+h
162−, If+, w−, I+, w+, I−, w−w−++++++P+i
161−, If+, w−, I+, w−, I+, w−++w−+++++P−
  • a Ten fecal samples collected from 11 December 1997 through 23 January 1998 from all calves tested negative for E. coli O157:H7; +, positive; −, negative.

  • b Calves 170, 169, 168, and 165 were located in the four pens on the left side of the room, while calves 171, 163, 162, and 161 were in the four pens on the right side of the room.

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

  • d Steer (171) contamination (29 January 1998) of feed and water containers of control animals.

  • 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 I, inoculation with 1 liter of water containing 104 CFU (26 January 1997) and 103 CFU FRIK 1275/ml (27 and 28 January 1998).

  • g All intestinal tract samples tested positive.

  • h Reticulum and rumen and their contents tested positive.

  • i Reticulum and contents tested positive.