design: Total DNA was extracted from 150 mg of fresh faeces using the ISOLATE Faecal DNA Kit (BioLine Australia) according to the manufacturers instructions. DNA samples were subjected to microbial diversity profiling at the Australian Genome Research Facility (Brisbane, Australia). Sequencing of the V3-V4 region (341F/806R) of the 16S rRNA gene was performed on Illumina MiSeq (300bp pair-end).