Figure 7From: Attenuated Salmonella typhimurium delivering DNA vaccine encoding duck enteritis virus UL24 induced systemic and mucosal immune responses and conferred good protection against challengeNumbers of ducklings surviving challenge with 1000 LD 50 of DEV. Six weeks after primary immunization, ducklings (10 ducklings per group) were orally challenged with 1000 lethal doses, 50% (LD50) of DEV. Mortality was monitored for 10 days after DEV challenge.Back to article page