Researchers at the Agricultural Research Service's Food and Feed Safety Research Unit in College Station, Texas, have discovered a practical method to reduce Salmonella typhimurium and E.coli 0157:H7 in pigs and cattle at slaughter. They have found that feeding pigs and cows low doses of sodium chlorate before slaughter can kill these pathogens.

ARS scientists have developed an animal model that shows sodium chlorate reduces the amount of these harmful bacteria in the intestinal
tract. The sodium chlorate works because Salmonella and E.coli 0157:H7 each contain a specific enzyme - respiratory nitrate reductase - that beneficial bacteria lack. This enzyme converts the sodium chlorate into chlorite, which kills the harmful bacteria but leaves the good ones intact.

In laboratory studies, 45 weaned pigs were fed as much as 0.04 grams of sodium chlorate per kilogram of body weight after being inoculated with Salmonella typhimurium. Within 16 hours, the treatment produced a 150-fold reduction in the number of pathogenic cells in the intestines.

Besides adding the chlorate to feed, the researchers suggest that a more realistic approach may be adding chlorate to the drinking water for the animals upon arrival at a processing facility. However, the Food and Drug Administration would need to approve any wide-scale use of the technique in food-processing facilities. USDA has applied for a patent on behalf of the researchers.