Gut microbiome associated with PRRS vaccine efficacy

A study led by researchers at Kansas State University aimed to identify gut microbiome characteristics associated with improved outcome in pigs immunized against porcine reproductive and respiratory syndrome virus (PRRSV), after co-infection with PRRSV and porcine circovirus type 2 (PCV2).

“Our latest work is focused on how the gut microbiome impacts the response of growing pigs to a respiratory vaccine,” said Megan Niederwerder, assistant professor of diagnostic medicine and pathobiology in the College of Veterinary Medicine at Kansas State University. “Beneficial microbes living in the gastrointestinal tract play an essential role in the development and regulation of immunity. We now understand that this role extends to viral respiratory vaccines in addition to viral respiratory diseases.”

Modified live virus vaccines are widely used to reduce PRRS-associated losses and decrease respiratory disease in pigs. Currently available vaccines, however, are generally considered inadequate for disease control and additional tools are necessary to reduce the effects of PRRS on swine, she said.

“The gut microbiome is one alternative tool that can improve response to PRRSV vaccines and PRRSV infection,” Niederwerder said. “In the current study, we identified several gut microbiome characteristics associated with improved growth rates of nursery pigs after PRRS vaccination and co-infection, including increased faecal bacterial diversity.”

Further gut microbiome characteristics associated with increased growth rates of vaccinated pigs included increased Bacteroides pectinophilus, decreased Mycoplasmataceae species diversity, higher Firmicutes: Bacteroidetes ratios, increased relative abundance of the phylum Spirochaetes, reduced relative abundance of the family Lachnospiraceae, and increased Lachnospiraceae species C6A11 and P6B14.

The researchers say the study provides evidence towards the gut microbiome playing a role in PRRS vaccine efficacy.

Article: Constance, L. A., Thissen, J. B., Jaing, C. J., McLoughlin, K. S., Rowland, R., Serão, N., Cino-Ozuna, A. G., Niederwerder, M. C. (2021). Gut microbiome associations with outcome following co-infection with porcine reproductive and respiratory syndrome virus (PRRSV) and porcine circovirus type 2 (PCV2) in pigs immunized with a PRRS modified live virus vaccine. Veterinary Microbiology, 254, 109018, doi: 10.1016/j.vetmic.2021.109018

[SOURCE: Kansas State Univeristy]