Abstract
1. Enterococcus cecorum (EC) infection in chicks must be prevented because of its severe pathogenicity in poultry farming. In this study, the combined sanitising effects of sodium hypochlorite (NaClO) and carbon dioxide microbubbles (CO2MB) on artificially applied EC on eggshells were clarified and the effectiveness for sanitising fertilised eggs was investigated.2. The number of surviving EC cells on eggshells decreased with increasing chlorine concentration and treatment time, with the NaClO solution containing CO2MB. The spray treatment of the NaClO solution containing CO2MB was more effective for sanitising EC.3. In addition, sanitisation of EC on fertilised eggs using a NaClO solution containing CO2MB was effective in preventing contamination in the setter, without negative effects on hatching or early growth of chicks.4. Using NaClO solution containing CO2MB was an effective method for sanitising EC on fertilised eggs.