ARS | Publication request: Efficacy of combination chemicals as sanitizers of Salmonella-inoculated broiler hatching eggshells

Submitted to: Journal of Applied Poultry Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 5, 2012
Publication Date: March 1, 2013
Citation: Buhr, R.J., Spickler, J.L., Ritter, A.R., Bourassa, D.V., Cox Jr, N.A., Richardson, L.J., Wilson, J.L. 2013. Efficacy of combination chemicals as sanitizers of Salmonella-inoculated broiler hatching eggshells. Journal of Applied Poultry Research. Vol.22 p.22:27-35..

Interpretive Summary: Cleaning broiler hatching eggs following collection provides an opportunity to reduce the eggshell bacterial load entering hatchery incubators, which can be subsequently carried with the chicks to the growout farm and ultimately into the processing plant. In two experiments we evaluated combination egg sanitizing chemicals containing ammonium chlorides, biguanide, bronopol, quaternary ammonium, or hydrogen peroxide for efficacy in eliminating inoculated Salmonella from the shell of broiler hatching eggs. These chemicals were compared to no treatment, water sprayed (to account for spray rinsing of eggshells independent of sanitization) and to 1.4% hydrogen peroxide, a demonstrated effective hatching egg sanitizer for Salmonella. All four combination chemicals tested significantly reduced the prevalence of Salmonella by 80 to 100% while the water sprayed controls had only a 9 to 20% reduction following water spray. The chemical containing 4 quaternary ammoniums and a biguanide (symbolized as 4NR4+BG) at 200 ppm was as effective as hydrogen peroxide at 1.4% in sanitizing hatching eggs for Salmonella when the inoculum levels were 10,000 cells (0% positive) or 1,000,000 cells/eggshell (only 3% positive). Following hatchability and chick quality trials the chemical 4NR4+BG should be considered for evaluation in commercial hatchery operations for the reduction of hatching eggshell carriage of Salmonella.

Technical Abstract: Sanitization of broiler hatching eggs provides an opportunity to reduce the eggshell bacterial load entering hatchery incubators, which can be subsequently carried with the chicks to the growout farm and ultimately into the processing plant. Two experiments evaluated combination chemicals containing ammonium chlorides (NH4Cl), biguanide (C2H7N5R, abbreviated BG), bronopol (C3H6BrNO4; abbreviated BP), quaternary ammonium (NR4), or hydrogen peroxide (H2O2) for efficacy in eliminating inoculated Salmonella from the shell of broiler hatching eggs. These chemicals were compared to no treatment, water sprayed (to account for spray rinsing of eggshells independent of sanitization) and to 1.4% H2O2, a demonstrated effective hatching egg sanitizer for Salmonella. All four combination chemicals tested (2NH4Cl+H2O2, 2NH4+BG+BP, 4NH4, and 4NH4+BG) significantly reduced the prevalence of Salmonella (80 to 100%) in comparison to the water sprayed controls (a 9 to 20% reduction following water spray). The chemical 4NR4+BG (containing 4 quaternary ammoniums and a biguanide) at 200 mg/L was as effective as H2O2 at 1.4% in sanitizing hatching eggs for both Salmonella strains when the inoculum levels were 10^4 (0% positive) or 10^6 cfu/eggshell (3% positive). Following hatchability and chick quality trials for 4NR4+BG, this chemical should be considered for evaluation in commercial hatchery operations for the reduction of hatching eggshell carriage of Salmonella.