The late pregnancy and lactation periods represent critical windows for maternal and infant health, during which the gut microbiome undergoes dynamic changes that influence immune development, metabolism, and overall well-being. This study investigated the effects of maternal supplementation with Bifidobacterium animalis subsp. lactis Probio-M8 (Probio-M8) during lactation on both dams and their offspring using a mouse model. Probiotic-treated dams exhibited significantly reduced body weight at weaning and increased serum IL-6 levels (P Alistipes indistinctus, Agathobacter sp., and Bifidobacterium pseudocatenulatum, were enriched in probiotic-fed dams, while pups showed increased abundance of Anaerobutyricum hallii and other beneficial species. Metagenomic and carbohydrate-active enzyme profiling revealed enhanced capacity for complex carbohydrate degradation in probiotic-exposed pups, suggesting improved metabolic adaptation during weaning. Fecal metabolomics further identified significant enrichment of pathways related to tyrosine metabolism and polyunsaturated fatty acid biosynthesis in pups, including α-linolenic acid metabolism, key processes linked to neurological development and immune regulation. Correlation analyses highlighted associations between these metabolic shifts and differentially abundant bacterial taxa, underscoring the interplay between microbiota composition and host physiology. Collectively, our findings demonstrate that maternal probiotic administration during lactation modulates both maternal and offspring gut ecosystems, promoting favorable microbial and metabolic profiles that may support growth, immunity, and developmental programming. These results provide mechanistic insights into how early-life microbial exposure via breastfeeding can be leveraged for nutritional interventions aimed at improving lifelong health outcomes.
Zhou et al. (2026) studied this question.