Delivery methods for commercial scale applications must be simple, inexpensive and cost-effective. The use of live vectors such as fowl adenoviruses (FAV) has previously been proven successful for the effective oral delivery of chicken interferon gamma to broilers under commercial growing conditions. FAV can be delivered via food or water or can be used as a spray. The ability of cytokines to modulate immune responses to vaccines and their therapeutic and growth promoting capability makes them an important component in future health management strategies for poultry. In this report, we describe the development of recombinant FAV vectors expressing chicken interleukin-2 (ChIL-2) and chicken myelomonocytic growth factor(cMGF). The ChIL-2 and cMGF genes were cloned into the right hand terminal region of FAV serotype 8, under the control of the adenovirus major late promoter. The in vitro biological activity of FAV-ChIL-2 and FAV-cMGF was comparable to that of the corresponding recombinant proteins expressed in prokaryotic (E. coli) and eukaryotic (COS cell) systems. These constructs may be particularly useful as therapeutics formucosal infections.