## 3 Results
The most abundant genera identified in the tested samples were _Prevotella_, _Bacteroides_, _Clostridium_ and _Fusobacterium_. _Bacteroides_, _Megamonas_ and _Selenomonas_ were significantly higher in MB in comparison to GS, while _Desulfonauticus_, _Streptococcus_, _Lactobacillus_, _Aerococcus_ and _Enterococcus_, were significantly higher in GS compared to MB (Table 5). The most abundant species were _Clostidium biferentans_, _Fusobacterium mortiferum_, _Lactobacillus murinus_, _Prevotella copri_ and _Blautia_ sp. Ser8. In particular, the species _Lactobacillus murinus_ and _Blautia_ sp. Ser8 were significantly higher in GS in comparison to MB, while _Clostridium biferentans_, _Fusobacterium mortiferum_ and _Prevotella copri_ were significantly higher in MB rather than in GS (Table 6). The species with a \(p\) value \(\geq\)0.01% were uncultured bacteria, _Bacteroides pleleius_, _Fusobacterium equinum_ and _Clostridium scindens_. Among all, the uncultured bacteria were significantly higher in GS in comparison to MB, while _Bacteroides uniformis_ was significantly lower in GS rather than in MB (Table 6). \begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & \multicolumn{2}{c}{**MB**} & \multicolumn{2}{c}{**GS**} \\ \hline
**Genus** & **Mean (\%)** & **std. dev. (\%)** & **Mean (\%)** & **std. dev. (\%)** & **\(p\) Values** \\ \hline _Microbacterium_ & 0.008 & 0.019 & 0.497 & 0.788 & 0.064 \\ _Anzerobiospirillum_ & 0.090 & 0.155 & 0.223 & 0.272 & 0.168 \\ _Pauibacillus_ & 0.521 & 0.471 & 0.634 & 0.374 & 0.512 \\ _Bacillus_ & 0.200 & 0.390 & 0.160 & 0.088 & 0.718 \\ _Thermoactinomyces_ & 0.009 & 0.010 & 0.133 & 0.246 & 0.124 \\ _Prevotella_ & 11.078 & 9.463 & 6.317 & 6.814 & 0.157 \\ _Bacteroides_ & 10.010 & 7.919 & 3.891 & 5.036 & 0.027 \\ _Parobacteroides_ & 0.080 & 0.199 & 0.119 & 0.138 & 0.570 \\ _Porphylomonas_ & 0.046 & 0.049 & 0.157 & 0.118 & 0.011 \\ _Barresiella_ & 0.023 & 0.033 & 0.118 & 0.111 & 0.017 \\ _Helicobacter_ & 0.124 & 0.217 & 0.003 & 0.002 & 0.056 \\ _Clostidium_ & 15.007 & 7.362 & 13.934 & 4.942 & 0.668 \\ _Blautia_ & 6.746 & 3.580 & 5.307 & 2.441 & 0.245 \\ _Ruminococcus_ & 5.411 & 2.917 & 3.892 & 0.998 & 0.086 \\ _Faecalibacterium_ & 3.290 & 3.013 & 2.432 & 2.158 & 0.415 \\ _Eubacterium_ & 1.987 & 1.350 & 1.753 & 1.586 & 0.699 \\ _Hespella_ & 1.141 & 0.728 & 0.778 & 0.265 & 0.101 \\ _Robinsoniella_ & 0.519 & 0.513 & 0.442 & 0.501 & 0.707 \\ _Coprococcus_ & 0.514 & 0.846 & 0.222 & 0.625 & 0.331 \\ _Roseburia_ & 0.479 & 0.527 & 0.133 & 0.127 & 0.031 \\ _Butytriibrio_ & 0.369 & 0.485 & 0.369 & 0.132 & 0.999 \\ _Lachmospin_ & 0.246 & 0.517 & 0.098 & 0.119 & 0.316 \\ _Peptostreptococcus_ & 0.215 & 0.127 & 0.148 & 0.063 & 0.097 \\ _Alkaliphilus_ & 0.201 & 0.427 & 0.093 & 0.097 & 0.372 \\ _Syntrophococcus_ & 0.105 & 0.326 & 0.001 & 0.001 & 0.253 \\ _Ethandigenens_ & 0.099 & 0.139 & 0.231 & 0.220 & 0.101 \\ _Butyriciococcus_ & 0.096 & 0.063 & 0.122 & 0.064 & 0.337 \\ _Sarcin_ & 0.082 & 0.305 & 0.162 & 0.364 & 0.569 \\ _Petrooccus_ & 0.037 & 0.064 & 0.222 & 0.102 & 0.000 \\ _Fusiblacter_ & 0.008 & 0.020 & 0.177 & 0.116 & 0.001 \\ _Collinsella_ & 2.176 & 1.793 & 1.329 & 0.544 & 0.113 \\ _Slackia_ & 0.926 & 0.759 & 0.726 & 0.365 & 0.394 \\ _Enterorhabdas_ & 0.233 & 0.197 & 0.222 & 0.068 & 0.845 \\ _Atopbium_ & 0.140 & 0.115 & 0.130 & 0.065 & 0.797 \\ _Desulfonauticus_ & 0.102 & 0.147 & 0.923 & 0.495 & 0.000 \\ _Escherichia_ & 0.009 & 0.023 & 0.249 & 0.156 & 0.000 \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Mean relative frequency of abundance (%) and corresponding standard deviation (SD) (%) of the genera identified in the caeca of mixed breeds (MB) and German Shepherd (GS) dogs. The species indicated are those showing a mean relative frequency of abundance \(\geq\) 0.1% in at least one group. \(p\) values in bold are those who are significantly different.