LAUSR

Simple Summary The composition of gut microbial communities can be altered by host diet shift. In this study, we investigated the microbiome composition of European hares and the potential changes in their gut communities after 4 days from the introduction in the diet of new nourishment. The control group was fed with standard fodder; the diet of the experimental group was integrated with apples and carrots. DNA was extracted from fresh faecal pellets and the V3-V4 hypervariable regions were amplified and sequenced using the Illumina MiSeq® platform. The amplicon sequence variants were classified into 735 bacterial genera belonging to 285 families and 36 phyla; the most abundant phyla represented by Bacteroidetes and Firmicutes. Experimental and control hares did not show statistically significant differences in their microbial communities suggesting the exposition time to a new diet should be extended to define the time frame necessary to affect microbiome composition. Abstract This study aimed to characterise the gut microbiome composition of European hares (Lepus europaeus) and its potential changes after a short-term diet modification. The high sensitivity of European hare to habitat changes makes this species a good model to analyse possible alterations in gut microbiome after the introduction of additional nourishment into the diet. In total, 20 pairs were chosen for the experiments; 10 pairs formed the control group and were fed with standard fodder. The other 10 pairs represented the experimental group, whose diet was integrated with apples and carrots. The DNA from fresh faecal pellets collected after 4 days from the start of the experiment was extracted and the V3-V4 hypervariable regions were amplified and sequenced using the Illumina MiSeq® platform. The obtained amplicon sequence variants were classified into 735 bacterial genera belonging to 285 families and 36 phyla. The control and the experimental groups appeared to have a homogenous dispersion for the two taxonomic levels analysed with the most abundant phyla represented by Bacteroidetes and Firmicutes. No difference between control and experimental samples was detected, suggesting that the short-term variation in food availability did not alter the hares’ gut microbiome. Further research is needed to estimate significant time threshold.