<i>Salmonella</i> Bacterin Vaccination Decreases Shedding and Colonization of <i>Salmonella</i> Typhimurium in Pigs

• Main Authors: Eduarda Alexandra Gonçalves de Oliveira Moura, Daniela Gomes da Silva, Caio Henrique Turco, Thainara Vitoria Carnevalli Sanches, Gabriel Yuri Storino, Henrique Meiroz de Souza Almeida, Marina Lopes Mechler-Dreibi, Isabela Peixoto Rabelo, Karina Sonalio, Luís Guilherme de Oliveira
• Format: Article
• Language: English
• Published: MDPI AG 2021-05-01
• Series: Microorganisms
• Subjects: piglets; diarrhea; immunoglobulin; salmonellosis; immunization; inactivated vaccine
• Online Access: https://www.mdpi.com/2076-2607/9/6/1163

Since the occurrence of swine salmonellosis has increased over time and control strategies other than biosecurity are highly recommended, the present study aimed to evaluate the efficacy of vaccination with <i>Salmonella</i> Choleraesuis and <i>Salmonella</i> Typhimurium bacterins in pigs. Two experimental groups were formed: G1, animals immunized with two doses of a commercial vaccine (<i>n</i> = 20); G2, control group (<i>n</i> = 20). After vaccination, all pigs were orally challenged (D0) with 10⁸ CFU of <i>Salmonella</i> Typhimurium and evaluated for 40 days. Every 10 days after D0, five piglets from each experimental group were euthanized and submitted to the necroscopic examination, when organ samples were collected. Blood samples and rectal swabs were collected before the first dose of the vaccine (D−42), before the second dose (D−21), before the challenge (D0), and thereafter, every three days until D39. Blood count, serum IgG measurement by ELISA, and the excretion of <i>Salmonella</i> Typhimurium in feces were evaluated. While the results from blood count and serum IgG concentration did not differ, the detection and excretion of <i>Salmonella</i> between G1 and G2 differed (<i>p</i> < 0.05). Therefore, it was observed that this vaccine partially protected the animals against experimental infection with <i>Salmonella</i> Typhimurium, reducing the excretion of bacteria in feces.