Differences in enteric pathogens and intestinal microbiota between diarrheic weaned piglets and healthy penmates

Area of Science:

• Veterinary Medicine
• Microbiology
• Animal Science

Background:

• Postweaning diarrhea (PWD) is a significant health issue in weaned pigs, with multifactorial causes.
• The specific roles of pathogens and the intestinal microbiota in PWD etiology are not fully understood.

Purpose of the Study:

• To investigate differences in pathogen prevalence and intestinal microbiota composition between healthy and diarrheic weaned pigs.
• To identify key etiological agents and microbial shifts associated with PWD.

Main Methods:

• Fecal samples from 277 pigs (152 diarrheic, 125 healthy) across 18 farms were analyzed.
• Pathogen detection (Rotavirus A, B, C, PEDV, E. coli virulence factors, C. difficile) using PCR.
• Intestinal microbiota profiling via 16S rRNA sequencing on 148 samples.

Main Results:

• Rotavirus A (RVA) and Rotavirus B (RVB) were significantly more prevalent in diarrheic pigs, with higher RVA viral load.
• VT2 toxin from E. coli was associated with diarrhea; other virulence factors were not.
• Fusobacteriota phylum and Enterobacteriaceae/Campylobacteria were enriched in diarrheic pigs, while Ruminococcaceae and Lactobacillus were associated with healthy pigs or RVA-negative status.

Conclusions:

• Rotavirus A appears to be a primary driver of PWD.
• Traditional E. coli virulence factors may have a limited role in PWD.
• Lactobacillus presence in RVA-negative pigs suggests a potential protective role against PWD.