Efficacy of Disinfectants for Sanitizing Boots Under Dairy Farm Conditions

Abstract

Ampicillin-resistant Escherichia coli (AR-E. coli), suspended in a manure slurry, was placed on rubber and plastic boot material surfaces to determine survival time. In addition, rubber boots were immersed in the bacteria- manure slurry, placed in water, and then several disinfectants were applied to the boots to determine the bacterial kill time. In the second phase of the study, boots were contaminated with the bacteria-manure slurry, and plastic and concrete surfaces were walked on to determine how far the bacteria could be tracked.
AR-E. coli was isolated from the surfaces of both rubber and plastic strips for up to one day after the strips were inoculated with in the AR-E. coli slurry, with the exception of rubber strips at the highest temperature tested. Alcohol and Roccal-D Plus appeared to be the most effective disinfectants used on rubber, followed by bleach. Betadine Solution, Nolvasan Solution and water showed similar efficacy. AR-E. coli could be isolated from boot tracks on plastic for nearly 400 ft (121.9 m) and from a concrete surface for up to 150 ft (47.7 m).
Results of this study emphasize the importance of time and temperature on the ability of disinfectants to eliminate bacterial contamination in manure and supports the use of biosecurity Good Management Practices (GMP’s) to control the movement of potentially pathogenic bacteria on dairies.