Gut microbiota developmental trajectories in min and DLY pigs during lactation and nursery stages and the alleviation of ETEC-induced diarrhea by fecal microbiota transplantation

Introduction The gut microbiota plays a vital role in porcine growth, intestinal barrier function, and disease resistance, yet the influence of host genetics on microbiota development and breed-specific phenotypes remains unclear. This study investigated gut microbiota dynamics in genetically distinct pig breeds and evaluated the functional impact of breed-specific microbiota on intestinal health. Methods A total of 76 healthy 3-day-old piglets from Min pigs and Duroc × Landrace × Yorkshire (DLY) pigs were monitored from day 3 to day 49. Microbiota composition was analyzed at eight developmental stages using high-resolution 2bRAD-M sequencing. Intestinal tissues were collected at day 49 for spatial microbiota profiling and barrier function assessment. Additionally, twelve 21-day-old DLY piglets were assigned to control, Enterotoxigenic Escherichia coli (ETEC) K88 challenge, and fecal microbiota transplantation (FMT) groups to evaluate the protective effects of Min pig microbiota. Results Significant breed-specific differences were observed in microbial composition, developmental trajectories, and ecological succession patterns. Min pigs exhibited higher microbial diversity and greater community stability during early weaning compared to DLY pigs, accompanied by improved intestinal barrier integrity and reduced diarrhea incidence. FMT from Min pigs significantly enhanced microbial diversity, strengthened intestinal barrier function, and alleviated diarrhea following ETEC challenge. Discussion These findings demonstrate that host genetics shapes gut microbiota development, influencing intestinal health and disease resistance. Microbiota derived from Min pigs confers protective effects against enteric infection, highlighting its potential as a microbial resource to improve gut health in commercial pig production.