|Nisbet, David - Dave|
Submitted to: Agriculture, Food and Analytical Bacteriology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/16/2011
Publication Date: 10/1/2012
Publication URL: http://handle.nal.usda.gov/10113/57358
Citation: Krueger, N.A., Edrington, T.S., Farrow, R.L., Hagevoort, R., Anderson, R.C., Loneragan, G.H., Callaway, T.R., Nisbet, D.J. 2012. Evaluation of an experimental sodium chlorate product, with and without nitroethane, on Salmonella in cull dairy cattle. Agriculture, Food and Analytical Bacteriology. 2:82-87. Interpretive Summary: This research was conducted to simulate real world application of feeding an experimental chlorate product, both with and without nitroethane, to evaluate its effectiveness in reducing populations of Salmonella in cull dairy cattle on a commercial dairy prior to entering the food chain. Results demonstrated that both treatments reduced the concentration of Salmonella in cull dairy cows to levels that can be effectively controlled by modern processing intervention strategies at the slaughter plant.
Technical Abstract: Ruminant animals are natural reservoirs for Salmonella. These bacteria can reduce nitrate to nitrite through the membrane bound enzyme nitrate reductase which also has the ability to reduce chlorate to the cytotoxic end-product chlorite. An experimental product containing sodium chlorate (ECP) has been investigated in recent years as a pre-harvest food safety strategy to reduce Salmonella. The addition of nitroethane has been shown to enhance the effectiveness of ECP. The objective of this research was to determine if feeding ECP, with and without nitroethane, is effective in reducing naturally occurring populations of Salmonella in cull dairy cattle on a commercial dairy prior to slaughter. Twelve cull dairy cows, dosed for two consecutive days with either 140 mg of ECP containing 30% sodium chlorate /kg BW/d or with 70 mg of the ECP plus 160 mg nitroethane /kg BW/d, were sampled 48 h post initial dose at 12 h intervals for Salmonella via fecal samples. Upon completion of the 48 h, sampling animals were necropsied, and gastro intestinal tissue and luminal content samples taken for bacterial enumeration. Results demonstrate that sodium chlorate can effectively reduce the Salmonella up to 5 log10 cfu/g feces in shedding animals. While the ECP did not kill 100% of the cultured Salmonella, it did significantly reduce populations in the high shedders to levels that are effectively controlled by modern processing intervention strategies.