16S rRNA amplicon sequencing
Genomic DNA was extracted from mouse fecal samples using the MagPure Soil DNA LQ Kit (Magen, Guangzhou, China). The V3-V4 hypervariable regions of the 16S rRNA gene were amplified using primers 343F (5'-TACGGRAGGCAGCAG-3') and 798R (5'-AGGGTATCTAATCCT-3'). Sequencing libraries were generated via a two-step PCR process, purified, quantified, and pooled. The final library was sequenced on the Illumina MiSeq platform.