|Bearson, Bradley - Brad|
|KICH, JALUSA - Embrapa-Pigs And Poultry|
|LEE, IN - Hannam University|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 9/25/2014
Publication Date: 11/10/2014
Citation: Bearson, B.L., Bearson, S.M., Kich, J.D., Lee, I.S. 2014. DIVA defense: Broad protection for salmonella suppression. Meeting Abstract. Symposium on Gut Health in Production of Food Animals. p. 12.
Technical Abstract: A live, attenuated Salmonella enterica serovar Typhimurium vaccine was developed to confer broad protection against multiple Salmonella serovars to prevent disease and reduce pathogen colonization and shedding. Two vaccine trials were performed in swine to determine the protection afforded by the vaccine to challenge with two distinct Salmonella serovars. In the first vaccine trial, pigs were administered two doses of the vaccine (vaccination and booster) and challenged with wild-type S. Typhimurium UK1 that causes gastroenteritis. The swine rectal temperatures and plasma IFN' levels were significantly reduced in vaccinated pigs compared to mock-vaccinated swine. Fecal shedding and tissue colonization with wild-type S. Typhimurium UK1 was significantly reduced in vaccinated pigs compared to mock-vaccinated swine. Furthermore, the vaccine strain did not induce a serological response to Salmonella LPS and therefore an ELISA can be used to differentiate infected from vaccinated animals (DIVA). In the second vaccine trial, pigs were administered a single dose of the vaccine and challenged with a virulent S. Choleraesuis that causes systemic disease in swine. Compared to the mock-vaccinated group, the vaccinated pigs exhibited significantly reduced rectal temperatures, serum IFN' levels, and tissue colonization. Furthermore, during the challenge period, the isolation of S. Choleraesuis from blood cultures was significantly greater in mock-vaccinated pigs compared to vaccinated swine. The data from these two vaccine trials indicate that the live, attenuated S. Typhimurium vaccine can both protect swine from Salmonella that cause systemic disease in pigs and also reduce the potential for transmission of Salmonella that cause foodborne disease in humans. Therefore, this dual-use Salmonella DIVA vaccine is intended to not only protect the health status of the swine herd to reduce production losses, but also support food safety and public health by reducing the spread of human foodborne Salmonella from pen to plate.