Abstract
Plasmid profiling was used to distinguish strains of lactobacilli inhabiting the digestive tract of piglets and the feces of sows. Fifteen plasmid profile types were detected among 328 isolates of lactobacilli. Plasmid profiling of lactobacilli permitted the following conclusions to be made: the maternal feces were a major source of lactobacilli colonizing the piglet digestive tract; the lactobacillus population of the gastric region of the piglet digestive tract was composed of lactobacillus strains different from those present in the rectal population; and a lactobacillus succession was observed in the digestive tract of piglets drawn from a single litter, and one plasmid profile type became dominant in the gastric region of these animals.