Submitted to: Journal of Applied Poultry Research
Publication Type: Peer reviewed journal
Publication Acceptance Date: 9/13/2007
Publication Date: 11/1/2007
Citation: Cox Jr, N.A., Richardson, L.J., Buhr, R.J., Musgrove, M.T., Berrang, M.E., Bright, W. 2007. Bactericidal effect of several chemicals on hatching eggs inoculated with Salmonella serovar Typhimurium. Journal of Applied Poultry Research. 16:(4)623-627. Interpretive Summary: Salmonella are known to cause acute bacterial gastroenteritis in humans and poultry products have been implicated as a significant source of these infections. Salmonella can be readily transferred from breeder flocks to the offspring through the egg. Therefore, companies routinely apply antimicrobials to fertile hatching eggs to reduce Salmonella presence. Hydrogen peroxide is the chemical of choice by many hatcheries however this chemical causes corrosion of the hatchery materials. In this study, several different types of antimicrobials were evaluated on their effectiveness to reduce Salmonella in fertile hatching eggs and a few of the antimicrobials tested were more effective than hydrogen peroxide.
Technical Abstract: Breeder flocks and commercial hatcheries represent an early contamination point for Salmonella entry into commercial integrated poultry operations. Utilizing effective antimicrobial treatments for hatching eggs is a critical part of reducing the incidence of Salmonella colonized chicks on the farm. The objective of this study was to evaluate the bactericidal effect of several chemicals on Salmonella contaminated hatching eggs. Four replications (n=10/treatment) were conducted to determine the efficacy of seven commercially available compounds. The compounds tested were: 1) hydrogen peroxide 2) water/oil emulsion droplets stabilized by detergent 3) peroxyacetic acid 4) four quaternary ammonium compounds attached to a polymer 5) two quaternary ammonium compounds, one biquanide compound and bronopol attached to a polymer 6) N-alkyl dimethyl benzyl ammonium chloride and stabilized urea and 7) polyhexamethylenebiquanide hydrochloride (PHMB). A naladixic acid resistant Salmonella serovar Typhimurium was inoculated (104 cfu/ml) onto fertile hatching eggs by drip inoculation. Controls included a positive control (no spray application) and a water control (spray containing water to take into account rinsing effects). Compounds 5 and 7 had a 100% reduction and both of these chemicals included a biquanide. Compounds 4 and 3 were also effective with a 95% and 93.5% reduction, respectively. Compounds 2 and 6 were the least effective of all chemicals with a reduction of 40% and 47.5% respectively. Hydrogen peroxide (Compound 1), which has been used by the poultry industry, had a 70% reduction and the water control produced a 10% reduction due to the rinsing effect. Several antimicrobials tested were more effective than hydrogen peroxide. More detailed studies will be required to adequately evaluate these antimicrobials. These will include a thorough investigation of hatchability and a more stringent test on effectiveness which will involve looking for the marker strain in hatched out chicks of the chemically treated eggs.