Calf Water Troughs as a Source of E. coli O157
J. Kirk, Veterinary Medicine Extension; C. Holmberg, Veterinary Medicine Teaching and Research Center; R. Atwill, Veterinary Medicine Extension
Studies in Washington and Wisconsin have suggested that water in feeding troughs for calves are transient sources of E. coli O157. In these colder climates, E. coli O157 wa s more commonly found in the warmer season. There were also more numerous isolations from water troughs used by recently weaned, grouped calves.
Problem: Do water troughs on California dairies harbor E. coli O157 similar to other reports?
Approach: With the assistance of University of California Cooperative Extension (UCCE) livestock advisors, 48 California dairies were sampled from Escondido through the central va lley and north to Fortuna. From these dairies, 85 water trough samples were collected from group pens of weaned calves.

Three (3) samples from three different dairies were positive for E. coli O157.

On re-sampling, all three were negative.

Three (3) other dairies had Salmonella in the water troughs.

The prevalence of E. coli O157-positive water troughs in California is similar to that in other states.