|Fox, J - TX A&M UNIVERSITY|
|Carstens, G - TX A&M UNIVERSITY|
|Miller, R - TX A&M UNIVERSITY|
|Jung, Yong Soo|
Submitted to: International Journal of Applied Research in Veterinary Medicine
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: April 29, 2005
Publication Date: July 1, 2005
Citation: Fox, J.T., Anderson, R.C., Carstens, G.E., Miller, R.K., Jung, Y., McReynolds, J.L., Callaway, T.R., Edrington, T.S., Nisbet, D.J. 2005. Effect of nitrate adaptation on the bactericidal activity of an experimental chlorate product against Escherichia coli in cattle. International Journal of Applied Research in Veterinary Medicine. 3:76-80. Interpretive Summary: Escherichia coli and Salmonella typhimurium are pathogenic bacteria that live in the gut of food producing animals such as cattle, pigs, and chickens. These pathogens can contaminate the food we eat during processing. Recently, a new experimental feed additive, called ECP, has been developed by the USDA and has been shown to kill these unwanted bacteria but not beneficial bacteria when fed to animals. In some studies with broilers and pigs, the ability of the feed additive to kill the unwanted bacteria was optimized by first feeding another additive, nitrate, before feeding the ECP. The nitrate pre-feeding worked by making the unwanted bacteria more susceptible to ECP. The objective of the presnt study was to see if nitrate pre-feeding would also work to enhance the bacterial killing activity of ECP against E. coli in cattle. Results indicate that nitrate pre-feeding was not needed in cattle as the ECP was just as effective at killing E. coli when fed without the nitrate pre-feeding. These results confirm that ECP can be used as a feed supplement to kill important foodborne pathogens in cattle and will help cattle producers learn how to most economically feed this food safety supplement. This work will ultimately help cattle producers produce safer and more affordable meat products for the American consumer.
Technical Abstract: An experimental chlorate product (ECP) developed by the USDA has been shown to have bactericidal effects against enteropathogens such as Escherichia coli. In studies with broilers and pigs, the bactericidal activity of ECP was enhanced by prior adaptation of gastrointestinal microflora to nitrate. The objective of this study was to examine the effects of nitrate adaptation on the bactericidal activity of ECP against E. coli in Holstein steers. Results indicate that ECP was effective at reducing E. coli. However, ECP did not reduce E. coli in a dose-dependent manner indicating that the highest ECP dose provided in this study exceeded that needed to be efficacious. Adapting gastrointestinal microflora with nitrate prior to feeding ECP did not improve efficacy of ECP against E. coli. Rapid reduction of nitrate in the rumen is implicated as a possible explanation for why adaption to nitrate did not enhance the bactericidal effects of ECP in cattle.