Evaluation of application methods for control of Aspergillus fumigatus proliferation on the air cell membrane of in ovo injected broiler eggs.

Three different techniques of applying fungicides and mold inhibitors were evaluated as control methods for Aspergillus fumigatus proliferation on the air cell membrane of eggs that were infertile or contained early dead embryos following in ovo egg injection. A controlled Aspergillus challenge model was utilized that simulates the natural occurrence of fungal growth following in ovo egg injection. Methods of application examined were egg shell spray, direct air cell application prior to Aspergillus challenge, and micro-aerosol fogging in the incubation compartment during Aspergillus challenge. Fungicides and mold inhibitors used included propionic acid, propionic acid plus ammonia, phenol, quaternary ammonium plus organic tin, hydrogen peroxide, enilconazole, and an aromatase inhibitor. When applied as egg shell spray treatments or micro-aerosol fog treatments, none of the products that were tested significantly reduced the incidence of mold proliferation on the air cell membrane when compared with untreated, but otherwise challenged, controls. When applied directly to the air cell membrane prior to fungal challenge, only enilconazole and the aromatase inhibitor significantly reduced the incidence of fungal proliferation when compared with appropriate controls.