The study was carried out in the AAALAC-accredited animal facility at the University of Maryland School of Medicine. Six groups of 8 one-day-old male and female SPAFAS White Leghorn Chickens, Gallus domesticus, were obtained from Charles River Laboratories (Connecticut). The animals were housed in brooder and grower cages (McMurray Hatcheries, Iowa). Feed (Teklad Japanese Quail Diet -3050, Harlan-Teklad, WI) and water were provided to the animals ad libitum. The study was performed in strict accordance with the ''Guide'' after approvals from the Animal Care and Use Committees of the Vaccine Research Center, NIH and the University of Maryland. DNA immunizations were performed as described at 0, 3 and 6 weeks. A total dose of 500 mg of one or a combination of the following DNA plasmids in a volume of 250 ml was administered to each animal: pCMV/ R, pCMV/R-HA 