Journal of Animal Science, Vol 80, Issue 6 1683-1689, Copyright © 2002 by American Society of Animal Science

JOURNAL ARTICLE

Sodium chlorate supplementation reduces E. coli O157:H7 populations in cattle

T. R. Callaway, R. C. Anderson, K. J. Genovese, T. L. Poole, T. J. Anderson, J. A. Byrd, L. F. Kubena and D. J. Nisbet
Food and Feed Safety Research Unit, Southern Plains Agricultural Research Center, Agricultural Research Service, USDA, College Station, TX 77845, USA. callaway@ffsru.tamu.edu

Cattle are a natural reservoir of the food-borne pathogen Escherichia coli O157:H7. Therefore, strategies that reduce E. coli O157:H7 prior to slaughter will reduce human exposures to this virulent pathogen. When bacteria that can anaerobically respire on nitrate (e.g., E. coli) are exposed to chlorate, they die because the intracellular enzyme nitrate reductase converts nitrate to nitrite, but also co-metabolically reduces chlorate to cytotoxic chlorite. Because chlorate is bactericidal only against nitrate reductase-positive bacteria, it has been suggested that chlorate supplementation be used as a strategy to reduce E. coli O157:H7 populations in cattle prior to harvest. Cattle (n = 8) were fed a feedlot-style high-grain diet experimentally infected with three strains of E. coli O157:H7. Cattle were given access to drinking water supplemented with 2.5 mM KNO3 and 100 mM NaCl (controls; n = 4) or 2.5 mM KNO3 and 100 mM NaClO3 (chlorate-treated; n = 4). Sodium chlorate treatment for 24 h reduced the population of all E. coli O157:H7 strains approximately two logs (10(4) to 10(2)) in the rumen and three logs (10(6) to 10(3)) in the feces. Chlorate treatment reduced total coliforms and generic E. coli from 106 to 10(4) in the rumen and by two logs throughout the rest of the gastrointestinal tract (ileum, cecum, colon, and rectum). Chlorate treatment reduced E. coli O157:H7 counts throughout the intestinal tract but did not alter total culturable anaerobic bacterial counts or the ruminal fermentation pattern. Therefore, it appears that chlorate supplementation is a viable potential strategy to reduce E. coli O157:H7 populations in cattle prior to harvest.

This article has been cited by other articles:

				C. E. Oliver, M. L. Bauer, J. S. Caton, R. C. Anderson, and D. J. Smith The in vitro reduction of sodium [36Cl]chlorate in bovine ruminal fluid J Anim Sci, August 1, 2007; 85(8): 2059 - 2068. [Abstract] [Full Text] [PDF]

				J. T. Fox, B. E. Depenbusch, J. S. Drouillard, and T. G. Nagaraja Dry-rolled or steam-flaked grain-based diets and fecal shedding of Escherichia coli O157 in feedlot cattle J Anim Sci, May 1, 2007; 85(5): 1207 - 1212. [Abstract] [Full Text] [PDF]

				S. W. Naylor, P. Nart, J. Sales, A. Flockhart, D. L. Gally, and J. C. Low Impact of the Direct Application of Therapeutic Agents to the Terminal Recta of Experimentally Colonized Calves on Escherichia coli O157:H7 Shedding Appl. Envir. Microbiol., March 1, 2007; 73(5): 1493 - 1500. [Abstract] [Full Text] [PDF]

				J. T. LeJeune and A. N. Wetzel Preharvest control of Escherichia coli O157 in cattle J Anim Sci, March 1, 2007; 85(13_suppl): E73 - E80. [Abstract] [Full Text] [PDF]

				R. W. Moore, J. A. Byrd, K. D. Knape, R. C. Anderson, T. R. Callaway, T. Edrington, L. F. Kubena, and D. J. Nisbet The Effect of an Experimental Chlorate Product on Salmonella Recovery of Turkeys when Administered Prior to Feed and Water Withdrawal Poult. Sci., December 1, 2006; 85(12): 2101 - 2105. [Abstract] [Full Text] [PDF]

				J. L. Morrow, F. M. Mitloehner, A. K. Johnson, M. L. Galyean, J. W. Dailey, T. S. Edrington, R. C. Anderson, K. J. Genovese, T. L. Poole, S. E. Duke, et al. Effect of water sprinkling on incidence of zoonotic pathogens in feedlot cattle J Anim Sci, August 1, 2005; 83(8): 1959 - 1966. [Abstract] [Full Text] [PDF]

				T. R. Callaway, R. C. Anderson, T. S. Edrington, K. J. Genovese, K. M. Bischoff, T. L. Poole, Y. S. Jung, R. B. Harvey, and D. J. Nisbet What are we doing about Escherichia coli O157:H7 in cattle? J Anim Sci, January 1, 2004; 82(13_suppl): E93 - 99. [Abstract] [Full Text] [PDF]

				T. R. Callaway, R. C. Anderson, T. S. Edrington, R. O. Elder, K. J. Genovese, K. M. Bischoff, T. L Poole, Y. S. Jung, R. B. Harvey, and D. J. Nisbet Preslaughter intervention strategies to reduce food-borne pathogens in food animals J Anim Sci, February 1, 2003; 81(14_suppl_2): E17 - 23. [Abstract] [Full Text] [PDF]

				D. O. Krause, W. J. M. Smith, L. L. Conlan, J. M. Gough, M. Anna Williamson, and C. S. McSweeney Diet influences the ecology of lactic acid bacteria and Escherichia coli along the digestive tract of cattle: neural networks and 16S rDNA Microbiology, January 1, 2003; 149(1): 57 - 65. [Abstract] [Full Text] [PDF]