Lactobacillus reuteri,a Gram-positive and obligately heterofermentative bacterium that colonises the gut of a variety of vertebrate species.Previous reported that Lactobacillus reuteri isolated from gut of mice,pig,and human is host-driven evolution.To gain insight into the evolution and adaptation,we have sequenced whole genome of 16Lactobacillus reuteri isolates from cow (4 strains),goat (5 strains),sheep (4 strains) and horse (3 strains).The comparative genomics of 37 strains of Lactobacillus reuteri was executed,including the previously completed genome of 21 strains.