Can new vaccine technologies against Mycoplasma hyopneumoniae influence the respiratory microbiota of pigs?

• Grant number: 23/00829-7
• Support Opportunities: Scholarships abroad - Research
• Start date: August 01, 2023
• End date: April 15, 2024
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Preventive Veterinary Medicine
• Principal Investigator: Luís Guilherme de Oliveira
• Grantee: Luís Guilherme de Oliveira
• Host Investigator: Marina Sibila Vidal
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil
• Institution abroad: Centre de Recerca en Sanitat Animal (CReSA), Spain

Abstract

Mycoplasma (M.) hyopneumoniae is a difficult-to-control bacterium since commercial vaccines do not prevent colonization and excretion. New experimental vaccine technology is available and can be a promising tool to prevent the disease. However, is unknowing if the respiratory microbiota can be altered by vaccination. Thus, the present study aims to experimentally evaluate the impact on the bacterial composition of the respiratory tract in pigs vaccinated with an oral vaccine consisting of a carrier-adjuvant (silica SBA-15) associated with a pool of immunogenic proteins from M. hyopneumoniae. To this, the oral vaccine will be administered to piglets born to gilts previously challenged with M. hyopneumoniae. A total of 60 piglets will be divided into four groups (n=15) submitted to different vaccination protocols as follows, Group 1: oral SBA15 + commercial vaccine at 24 days after weaning, G2: oral vaccine on the third day of life + commercial vaccine at 24 days, G3: commercial vaccine at 24 days and G4: commercial vaccine + oral vaccine at 24 days. Nasal swabs will be collected periodically from the third day of life until the 73rd day. At 41 days of life, 12 infected-seeders piglets, inoculated with M. hyopneumoniae, will be insert into the pen from groups (1 to 4) to increase the infection pressure during the nursery period. At the end of the study, at 73 days, all piglets will be euthanized and necropsied for evaluation of the lungs and collection bronchoalveolar fluid (BALF). The DNA will extract from individual samples, and each group will have the samples pooled and submit to next-generation sequencing (NGS). Taxonomic analysis, alpha and beta diversity indexes, and Weighted unifrac, and Unweighted unifrac distances will calculate. The study of vaccination influence in the composition of the bacterial diversity on the respiratory tract can provide valuable information for control of Enzootic Pneumonia. (AU)