A multi-pronged approach to the search for an alternative to formaldehyde as an egg disinfectant without affecting worker health, hatching, or broiler production parameters

Research was carried out to determine the effectiveness of 4 hatching eggs disinfection processes (i.e., disinfecting products and administration method) using a multi-pronged approach assessing the reduction of microbial eggshell contamination, the effects on worker exposure, hatching results and broiler performance, and, finally, suitability for use in commercial hatcheries. The 4 disinfection processes were: sodium dichlorocyanurate (DC) by thermonebulization, hydrogen peroxide 6% by nebulization (HP6), electrolyzed oxidizing water (EOW) by fogging, and hydrogen peroxide 30% vapor (HP30). In order to meet commercial hatchery conditions, the tested products were applied in an experimental hatchery by aerial disinfection in a dedicated room, not sprayed directly onto the eggs. Compared to the untreated control group, eggshell microbial load was significantly decreased by over 1 log10 cfu per egg in groups DC and HP30. These results were confirmed during a second experiment. In addition, these 2 products comply with legal requirements on worker exposure. Fertility and hatching results were significantly higher in group HP30 than in group DC, with no impact on chick quality and subsequent broiler performance. Under these study conditions, the disinfection process (i.e., administration of the product, contact with the eggs and aeration) lasted 65 min in group DC vs. 135 min in group HP30. When considering commercial hatchery conditions, this difference in application time confers a clear advantage on the DC process. Moreover, the investment required for HP30 is much higher than for DC. Overall, HP30 presented a clear advantage for hatching results whereas DC is a relatively more practical and less expensive disinfection process. To our knowledge, this is the first report on the use of hydrogen peroxide vapor as an egg disinfection process. Further research is needed to confirm the results of this study under commercial hatchery conditions.