The present invention relates to molecular biology, molecular genetics, and bioprocessing. The embodiments provide for compositions and methods for producing a biological product, such as an immunogenic agent, in an embryonated egg by introducing into the egg a RNA effector molecule capable of modulating expression of a target gene, wherein the modulation enhances production of the biological product in the egg. These methods provide for RNAi-based approaches to optimize the production of biologics from embryonated eggs, such as the production of viral vaccines including seasonal and pandemic flu vaccines. The invention also relates to molecules, reagents, cells, and kits useful for carrying out the methods, and biological products produced by the methods.