Page Banner

United States Department of Agriculture

Agricultural Research Service

Research Project: MICROBIAL ECOLOGY OF HUMAN PATHOGENS RELATIVE TO POULTRY PROCESSING Title: Forced Hot Air to Dry Feces and Kill Bacteria on Transport Cage Flooring

Authors
item Berrang, Mark
item Meinersmann, Richard
item Hofacre, Charles -

Submitted to: Journal of Applied Poultry Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: July 27, 2011
Publication Date: December 1, 2011
Citation: Berrang, M.E., Meinersmann, R.J., Hofacre, C.L. 2011. Forced Hot Air to Dry Feces and Kill Bacteria on Transport Cage Flooring. Journal of Applied Poultry Research. 20(4):567-572.

Interpretive Summary: Broiler chickens can become intestinally colonized with bacteria such as Campylobacter that make humans sick. At market age, broilers are placed in wire cages with fiberglass floors to be carried to the slaughter plant. During transport, broilers defecate in the cages and in the case of Campylobacter positive flocks, transport cages can be contaminated facilitating cross contamination of the next flock transported in the same cages. Earlier work has shown that drying soiled or washed cages at ambient temperatures can lower or even eliminate detectable Campylobacter on cage flooring. However, to be effective, such drying must be done for 24 to 48 hours which given the size and expense of transport cages is impractical. We tested the use of hot flowing air to speed the drying process. Flowing hot air was compared to flowing un-heated air and static hot air as well as an ambient air control to lessen the number of Campylobacter, E. coli and coliforms on small squares of fecally soiled transport cage flooring. When applied after a water spray wash treatment, hot flowing air at about 50oC for 15 min. lowered the numbers of Campylobacter to an undetectable level. Static heat at similar temperatures was not nearly as effective and un-heated flowing air was moderately effective but less so than the hot air. The use of hot flowing air provides a tremendous saving in dry time, suggesting a potential commercial application. Processors may be able to use a forced hot air treatment to dry cages between flocks, lessening the number of Campylobacter on cage flooring thereby decreasing the potential of cross contamination during live haul.

Technical Abstract: Due to fecal shedding from positive birds, broiler transport cages can be contaminated with human bacterial pathogens leading to cross contamination of previously negative broilers during live haul. Earlier work has shown that drying soiled or washed cages for 24 to 48 hours can lower or even eliminate detectable Campylobacter on cage flooring. Since extended drying times are impractical, we tested the use of hot flowing air to speed the process. To determine if the effect was due to heat alone or flowing air alone, hot flowing air was compared to un-heated flowing air and static hot air as well as to a bench-top control. The number of Campylobacter, E. coli and coliforms on small squares of washed or un-washed, fecally soiled transport cage flooring was measured before and after drying treatments. When applied after a water spray wash treatment, flowing air at about 50oC for 15 minutes lowered the numbers of Campylobacter to an undetectable level. This represents a tremendous savings in drying time and suggests a potential commercial application. Static heat at similar temperatures was not nearly as effective and un-heated flowing air was moderately effective but less so than the hot air. Processors may be able to use a forced hot air treatment to dry cages between flocks, lessening the number of Campylobacter on cage flooring thereby decreasing the potential of cross contamination during live haul.

Last Modified: 10/25/2014