## 3 Results  
The most abundant phyla identified in the dog feces were represented by Firmicutes, Bacteroidetes and Fusobacteria (Table 1). The phylum Bacteroidetes was significantly higher in MB in comparison to GS, while Proteobacteria was significantly higher in GS rather than in MB (Table 1). The most abundant classes were Bacteroidia, Clostridia and Fusobacteria (Table 2). Among the classes with a relative mean frequency of abundance \(>\)0.1%, Bacilli, Delataproteobacteria and Gammaproteobacteria were significantly higher in GS in comparison to MB. On the contrary, Bacteroidia and Negativicutes were significantly higher in MB rather than in GS (Table 2). The most abundant orders were Bacteroidales, Clostridiales, Lactobacillus and Fusobacterialies. The order Bacteroidales, as well as Selenomonadales, was significantly higher in MB than in GS, while Lactobacillus and Desulfovibrionales were significantly higher in GS in comparison to MB (Table 3). The most abundant families in the tested feces were Prevotellaceae, Bacteroidetes, Clostridiaceae and Fusobacteria (Table 4). The abundance of the families Bacteriadecae, Ruminococcaceae and Veillonellaceae were significantly higher in MB than in GS. On the contrary Microbiaceae, Streptococcus, Lactobacallaceae, Aerococaceae and Enterococcaceae were significantly higher in GS in comparison to MB (Table 4). \begin{table}
\begin{tabular}{c c c c c c} \hline  & \multicolumn{2}{c}{**MB**} & \multicolumn{2}{c}{**GS**} \\ \hline
**Phylum** & **Mean (\%)** & **std. dev. (\%)** & **Mean (\%)** & **PT std. dev. (\%)** & \(p\) Values** \\ \hline _Frimicutes_ & 55.247 & 13.880 & 55.695 & 14.042 & 0.937 \\ _Fusobacteria_ & 16.599 & 9.218 & 11.296 & 6.569 & 0.106 \\ _Bacteroidetes_ & 21.306 & 11.162 & 10.742 & 10.611 & 0.024 \\ _Actinobacteria_ & 3.608 & 2.868 & 3.453 & 1.827 & 0.871 \\ _Proteobacteria_ & 0.540 & 0.293 & 1.916 & 0.756 & 0.000 \\ \hline \end{tabular}
\end{table} 
Table 1: Mean relative frequency of abundance (%) and corresponding standard deviation (SD) (%) of the phyla 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 significantly different. \begin{table}
\begin{tabular}{c c c c c c} \hline  & \multicolumn{2}{c}{**MB**} & \multicolumn{2}{c}{**GS**} \\ \hline
**Class** & **Mean (\%)** & **std. dev. (\%)** & **Mean (\%)** & **std. dev. (\%)** & \(p\) Values** \\ \hline _Actinobacteria_ & 3.608 & 2.868 & 3.453 & 1.827 & 0.871 \\ _Bacteroidia_ & 21.298 & 11.157 & 10.724 & 10.603 & 0.023 \\ _Closridia_ & 39.318 & 11.190 & 33.425 & 8.456 & 0.146 \\ _Bacillus_ & 2.019 & 1.476 & 14.761 & 7.947 & 0.000 \\ _Erysipelotrichi_ & 8.471 & 7.689 & 4.664 & 3.423 & 0.113 \\ _Negativicutes_ & 5.439 & 3.881 & 2.846 & 1.723 & 0.037 \\ _Fusobacteria_ & 16.599 & 9.218 & 11.296 & 6.569 & 0.106 \\ _Delataproteobacteria_ & 0.158 & 0.217 & 0.973 & 0.504 & 0.000 \\ _Gammaproteobacteria_ & 0.161 & 0.169 & 0.825 & 0.681 & 0.008 \\ _Epsilonproteobacteria_ & 0.161 & 0.225 & 0.022 & 0.016 & 0.037 \\ \hline \end{tabular}
\end{table} 
Table 2: Mean relative frequency of abundance (%) and corresponding standard deviation (SD) (%) of the classes 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.