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Effect of Water Chlorination on Prevalence of Escherichia coli O157:H7 and Campylobacter in Feedlot Cattle (1999-04281)

Bohach, Carolyn; Besser, Thomas
Washington State University
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Our research question is: "Does providing cattle with a cleaner water supply reduce the number of cattle infected with E. coli O157:H7 and Campylobacter?"

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Cattle slaughtered while infected with bacteria such as E. coli O157:H7 or Campylobacter spp. are a probable source of these bacteria in contaminated beef products, and eventually in humans consuming these food products.

Our preliminary data leads us to believe that infection of cattle with these agents, like human infections, most often follows their eating contaminated feeds or drinking contaminated water. E. coli O157:H7 can be frequently isolated from cattle watertroughs,and has been shown to persist in troughs for months, so water is a logical starting point for control of these infections.

We will chlorinate the water supplies of 32 pens of feedlot cattle in two feedlots through the feeding period and compare the infection rate in these cattle to that of cattle consuming non-chlorinated water.

Also, we will evaluate the effect of chlorination on water consumption and weight gains. If chlorination of cattle water reduces cattle infections with bacteria that cause human disease, but is neutral or beneficial on cattle welfare and weight gain,this will be the first proven management practice enabling beef producers to reduce the risk of human disease due to these food-borne enteropathogenic bacteria.

Project number
Prevention and Control
Risk Assessment, Management, and Communication
Escherichia coli