The bacterial communities associated with fecal types and body weight of rex rabbits

Rex rabbit is an important small herbivore for fur and meat production. However, little is known about the gut microbiota in rex rabbit, especially regarding their relationship with different fecal types and growth of the hosts. We characterized the microbiota of both hard and soft feces from rex rabbits with high and low body weight by using the Illumina MiSeq platform targeting the V4 region of the 16S rDNA. High weight rex rabbits possess distinctive microbiota in hard feces, but not in soft feces, from the low weight group. We detected the overrepresentation of several genera such as YS2/Cyanobacteria, and Bacteroidales and underrepresentation of genera such as Anaeroplasma spp. and Clostridiaceae in high weight hard feces. Between fecal types, several bacterial taxa such as Ruminococcaceae, and Akkermansia spp. were enriched in soft feces. PICRUSt analysis revealed that metabolic pathways such as "stilbenoid, diarylheptanoid, gingerol biosynthesis" were enriched in high weight rabbits, and pathways related to "xenobiotics biodegradation" and "various types of N-glycan biosynthesis" were overrepresented in rabbit soft feces. Our study provides foundation to generate hypothesis aiming to test the roles that different bacterial taxa play in the growth and caecotrophy of rex rabbits.