Cohousing or cross-fostering followed by cohousing do not normalize the microbiomes of genetically distinct adult mice

DNA extraction from fecal samples was performed using QIAamp PowerFecal Pro DNA Kit. Barcoded dual-index universal bacterial primers 563F and 926R were used to PCR-amplify the V4-V5 hypervariable region of the 16S rRNA gene. Illumina compatible libraries were generated using the Qiagen QIASeq 1-step amplicon kit and sequencing was performed on the Illumina MiSeq platform using 2x250 paired-end reads. Raw gene sequence data was demultiplexed and processed through the DADA2 pipeline in R Studio. Amplicon sequence variants (ASVs) were identified, and taxonomy was assigned on to the family- or genus-level using the Silva NR99 database.