Efficiency of Commercial and Test Vaccines Against Lawsonia intracellularis on Clinical and Immunological Parameters in Swine: A Systematic Review

Abstract

Lawsonia intracellularis is a gram-negative obligate intracellular bacterium causing Proliferative Enteropathy in pigs, leading to significant economic losses in the swine industry. Vaccination offers an alternative to antibiotics for controlling this pathogen. This systematic review evaluates the efficacy of commercial and experimental vaccines against Lawsonia intracellularis in pigs, focusing on clinical outcomes and immunological responses. Following PRISMA guidelines, databases including PubMed, Google Scholar, CABI Digital Library, and Agricola/USDA were searched for studies from the past decade. Selected studies were assessed for bias using SYRCLE’s RoB tool. Data on weight gain, pathogen shedding, mortality, and immune responses were extracted and analyzed. Out of 824 identified articles, 9 studies met the inclusion criteria. Results indicated that vaccinated pigs showed reduced fecal shedding of L. intracellularis , lower mortality rates, and enhanced immune responses compared to non-vaccinated controls. Specific vaccines increased IFN-γ production, a crucial cytokine for Th1 responses against intracellular pathogens. Vaccination is an effective strategy to control Lawsonia intracellularis infection in swine, reducing disease symptoms and transmission. Continued research is necessary to optimize vaccination protocols and assess long-term economic impacts.

Bibliographic Information