Yeast probiotic protects gut microbiota diversity and metabolic potential against Cryptosporidiosis-induced disruption in goat kids.

Cryptosporidiosis, caused by Cryptosporidium parvum, is a major cause of enteric disease and gut microbiota disruption in neonatal ruminants. It can lead to impaired growth, increased susceptibility to pathogens, and long-term gut dysfunction. In this study, we investigated whether supplementation with a live yeast probiotic (Saccharomyces cerevisiae Sc47) could help preserve gut microbiota resilience and functional homeostasis during an experimental C. parvum oral infection in goat kids. Thirty male French Alpine goat kids were assigned to three groups: uninfected control (healthy), infected, and infected with yeast supplementation. Longitudinal 16S rRNA gene sequencing, network analysis, and functional metagenomic predictions were used to assess microbial diversity, community composition, co-occurrence patterns, and metabolic potential, with a focus on short-chain fatty acid (SCFA) biosynthesis. Infection induced marked dysbiosis, characterised by a substantial reduction in microbial richness and a widespread loss of SCFA-producing commensals and metabolic functions. In contrast, yeast supplementation significantly reduced oocyst excretion by more than 84% throughout the experiment, attenuated pathogen-induced community shifts, and maintained beneficial genera such as Butyricicoccus and members of the Oscillospiraceae family. Furthermore, network analysis revealed that probiotic treatment preserved microbial association structures and reduced community fragmentation. Consistent with these findings, functional profiling showed the retention of pathways involved in carbohydrate metabolism, amino acid biosynthesis, and SCFA production, suggesting enhanced microbiota resilience. These findings demonstrate that S. cerevisiae supplementation can mitigate infection-associated dysbiosis by controlling pathogenic overgrowth while sustaining commensal bacterial stability and functional capacity. This highlights its potential as a microbiota-targeted strategy to support gut health in neonatal ruminants.