library_construction_protocol: Total genomic DNA was extracted from colonic content samples using the CTAB/SDS method. DNA purity and concentration were assessed by agarose gel electrophoresis and diluted to 1 ng/μL with sterile water. The 16S rRNA V4 region was amplified with primers 515F and 806R using Phusion® High-Fidelity PCR Master Mix. PCR products were purified with magnetic beads, quantified, and pooled. Libraries were constructed using the TruSeq® DNA PCR-Free Sample Preparation Kit and sequenced on the Illumina NovaSeq 6000 platform.